Research Publications
Browse peer-reviewed journal articles, conference papers, and scholarly publications. Use the filters below to refine results by type, author, year, or research area.
1.
Kumar, C. S. C.; Ramachandra, M. N.; Lohith, K. S. M.; Padmavathy, N.; Sumesh, P.; Chandraju, S.
CoCu2O4 Modified Electrodes via Facile Synthesis for Ultrasensitive Dopamine Detection in Physiological Conditions Journal Article
In: Electrochimica Acta, vol. 548, 2026, ISBN: 00134686 (ISSN), (0).
@article{709,
title = {CoCu2O4 Modified Electrodes via Facile Synthesis for Ultrasensitive Dopamine Detection in Physiological Conditions},
author = {C. S. C. Kumar and M. N. Ramachandra and K. S. M. Lohith and N. Padmavathy and P. Sumesh and S. Chandraju},
url = {https://www.sciencedirect.com/science/article/abs/pii/S0013468625022492?via%3Dihub},
doi = {10.1016/j.electacta.2025.147892},
isbn = {00134686 (ISSN)},
year = {2026},
date = {2026-01-01},
journal = {Electrochimica Acta},
volume = {548},
publisher = {Elsevier Ltd},
abstract = {In this study, we modified a glassy carbon electrode (GCE) with CoCu<inf>2</inf>O<inf>4</inf> nanoparticles (NPs) to create an electrochemical sensor designed for the sensitive and selective detection of dopamine (DA). The CoCu<inf>2</inf>O<inf>4</inf> NPs were synthesized using a solution combustion method, producing porous, loosely packed nanostructures that provide abundant active sites for electrochemical reactions. PXRD coupled with Rietveld refinement confirmed the formation of a single-phase spinel, with a lattice constant of 8.386 Å and an average crystallite size of 18.58 nm. Examination of the surface morphology using SEM revealed porous, agglomerated features, while EDX verified a near-stoichiometric distribution of cobalt, copper, and oxygen within the material. The modified electrode, optimized with a 5 mg CoCu<inf>2</inf>O<inf>4</inf> coating, exhibited a 75 % enhancement in electrochemical response relative to the bare GCE. Operating at physiological pH 7.0, the CoCu<inf>2</inf>O<inf>4</inf> modified GCE exhibited a well-defined redox signal with a linear relationship between DA concentration and current response over 1–8 µM ( R 2 = 0.998). The limit of detection (LOD) was 0.029 ± 0.002 µM, and the limit of quantification (LOQ) was 0.49 ± 0.03 µM, highlighting the sensor’s high sensitivity. Stability assessments indicated 92 % retention of the initial response after one week, and repeatability was confirmed with a relative standard deviation (RSD) of 3.0 %. These findings establish the CoCu<inf>2</inf>O<inf>4</inf> modified GCE as a reliable platform for precise DA quantification, suitable for biomedical and analytical applications.},
note = {0},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
In this study, we modified a glassy carbon electrode (GCE) with CoCu<inf>2</inf>O<inf>4</inf> nanoparticles (NPs) to create an electrochemical sensor designed for the sensitive and selective detection of dopamine (DA). The CoCu<inf>2</inf>O<inf>4</inf> NPs were synthesized using a solution combustion method, producing porous, loosely packed nanostructures that provide abundant active sites for electrochemical reactions. PXRD coupled with Rietveld refinement confirmed the formation of a single-phase spinel, with a lattice constant of 8.386 Å and an average crystallite size of 18.58 nm. Examination of the surface morphology using SEM revealed porous, agglomerated features, while EDX verified a near-stoichiometric distribution of cobalt, copper, and oxygen within the material. The modified electrode, optimized with a 5 mg CoCu<inf>2</inf>O<inf>4</inf> coating, exhibited a 75 % enhancement in electrochemical response relative to the bare GCE. Operating at physiological pH 7.0, the CoCu<inf>2</inf>O<inf>4</inf> modified GCE exhibited a well-defined redox signal with a linear relationship between DA concentration and current response over 1–8 µM ( R 2 = 0.998). The limit of detection (LOD) was 0.029 ± 0.002 µM, and the limit of quantification (LOQ) was 0.49 ± 0.03 µM, highlighting the sensor’s high sensitivity. Stability assessments indicated 92 % retention of the initial response after one week, and repeatability was confirmed with a relative standard deviation (RSD) of 3.0 %. These findings establish the CoCu<inf>2</inf>O<inf>4</inf> modified GCE as a reliable platform for precise DA quantification, suitable for biomedical and analytical applications.
2.
Malini, M. R.; Devendra, B. K.; Panchami, H. R.; Kottam, N.; Krishna, B. S.
Carbon quantum dots: An overview of their synthesis from natural plant sources, and their potential use as antimicrobial agents Journal Article
In: Synthetic Metals, vol. 316, 2026, ISBN: 03796779 (ISSN), (0).
@article{669,
title = {Carbon quantum dots: An overview of their synthesis from natural plant sources, and their potential use as antimicrobial agents},
author = {M. R. Malini and B. K. Devendra and H. R. Panchami and N. Kottam and B. S. Krishna},
url = {https://www.sciencedirect.com/science/article/pii/S0379677925001535?via%3Dihub},
doi = {10.1016/j.synthmet.2025.117977},
isbn = {03796779 (ISSN)},
year = {2026},
date = {2026-01-01},
journal = {Synthetic Metals},
volume = {316},
publisher = {Elsevier Ltd},
abstract = {The serendipitous discovery of carbon quantum dots (CQDs), while purifying electrophoretically, single-walled carbon nanotubes (SWNTs) obtained from the soot of an arc-discharge, ignited a global interest in these carbon nanoparticles, due to their potential uses in a broad spectrum of studies like drug delivery, fluorescence, and catalysis. Their low toxicity and high stability endow them with potential medical uses, which hints at the need for CQDs in large quantities. Thus, a sustainable synthesis of CQDs has to be worked out to ensure the minimum use of energy and toxic chemical substances. A ‘top-down’ route to their synthesis involves the disintegration of relatively larger carbon structures like carbon nanotubes, nanodiamonds, and graphite, using energy-intensive processes, such as photoablation, arc discharge, and electrochemical techniques. An alternative to this is a ‘bottom-up’ method, which minimizes energy's utility, and can be achieved through the green synthesis of CQDs, from various plant sources, like herbs and the nightshades (family Solanaceae). Some of these naturally-derived CQDS have exhibited striking antimicrobial activity and cytotoxicity, which makes them potentially useful in therapeutics for bacterial infections and carcinomas. This review aims to discuss the synthesis and applications of such CQDs derived from herbal medicine (HM-CDs).},
note = {0},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
The serendipitous discovery of carbon quantum dots (CQDs), while purifying electrophoretically, single-walled carbon nanotubes (SWNTs) obtained from the soot of an arc-discharge, ignited a global interest in these carbon nanoparticles, due to their potential uses in a broad spectrum of studies like drug delivery, fluorescence, and catalysis. Their low toxicity and high stability endow them with potential medical uses, which hints at the need for CQDs in large quantities. Thus, a sustainable synthesis of CQDs has to be worked out to ensure the minimum use of energy and toxic chemical substances. A ‘top-down’ route to their synthesis involves the disintegration of relatively larger carbon structures like carbon nanotubes, nanodiamonds, and graphite, using energy-intensive processes, such as photoablation, arc discharge, and electrochemical techniques. An alternative to this is a ‘bottom-up’ method, which minimizes energy's utility, and can be achieved through the green synthesis of CQDs, from various plant sources, like herbs and the nightshades (family Solanaceae). Some of these naturally-derived CQDS have exhibited striking antimicrobial activity and cytotoxicity, which makes them potentially useful in therapeutics for bacterial infections and carcinomas. This review aims to discuss the synthesis and applications of such CQDs derived from herbal medicine (HM-CDs).
3.
Basavaraja, Venkappanavara; S, Shiva; S, Ganga; Naikodi, Dr. Chandrakant; Srinivas, Badrinath; Rao, B
Physical File Locking System Using IoT Book
2025.
@book{599,
title = {Physical File Locking System Using IoT},
author = {Venkappanavara Basavaraja and Shiva S and Ganga S and Dr. Chandrakant Naikodi and Badrinath Srinivas and B Rao},
url = {https://ieeexplore.ieee.org/document/11071049},
doi = {10.1109/OTCON65728.2025.11071049},
year = {2025},
date = {2025-01-01},
pages = {1-6,},
abstract = {Combining the Internet of Things (IoT) and biometric authentication has transformed security solutions across various sectors. This paper introduces a novel method for securing physical file access through an IoT-enabled fabric belt equipped with biometric finger sensors. To ensure thorough user identification, finger sensors are strategically placed on the top left, top right, bottom left, and bottom right side of the belt. This innovative approach offers significant benefits over conventional access control systems. Biometric verification adds robust security by requiring authentication from multiple positions. The method also reduces the risk of unauthorized entry by eliminating the need for traditional keys or access cards, which can be lost or stolen. Additionally, IoT integration allows for remote monitoring and management of access logs, improving accountability and audit ability. For enhanced security, the system can mandate that fingerprints from different users match on opposite sides of the belt to unlock the file. By merging IoT and biometric technology, this solution provides a reliable and intuitive way to manage access to physical files. Its scalability and adaptability make it suitable for applications demanding high-security measures while maintaining convenience and efficiency for authorized users.},
keywords = {CHEM},
pubstate = {published},
tppubtype = {book}
}
Combining the Internet of Things (IoT) and biometric authentication has transformed security solutions across various sectors. This paper introduces a novel method for securing physical file access through an IoT-enabled fabric belt equipped with biometric finger sensors. To ensure thorough user identification, finger sensors are strategically placed on the top left, top right, bottom left, and bottom right side of the belt. This innovative approach offers significant benefits over conventional access control systems. Biometric verification adds robust security by requiring authentication from multiple positions. The method also reduces the risk of unauthorized entry by eliminating the need for traditional keys or access cards, which can be lost or stolen. Additionally, IoT integration allows for remote monitoring and management of access logs, improving accountability and audit ability. For enhanced security, the system can mandate that fingerprints from different users match on opposite sides of the belt to unlock the file. By merging IoT and biometric technology, this solution provides a reliable and intuitive way to manage access to physical files. Its scalability and adaptability make it suitable for applications demanding high-security measures while maintaining convenience and efficiency for authorized users.
4.
Hungund, Basavaraj; Tennalli, Gururaj; Hegde, Namratha; Haripriya, G; Shiralgi, Yallappa
In: vol. 37, 2025.
@article{598,
title = {Phytochemical Screening, GCMS-LCMS Analysis of Bioactive Compounds from Methanolic Extract of Eichhornia crassipes: In vitro Cytotoxic Effect against MCF7 Cell Line},
author = {Basavaraj Hungund and Gururaj Tennalli and Namratha Hegde and G Haripriya and Yallappa Shiralgi},
url = {https://asianpubs.org/index.php/ajchem/article/view/37_6_17},
doi = {10.14233/ajchem.2025.33738},
year = {2025},
date = {2025-01-01},
volume = {37},
abstract = {Eichhornia crassipes, commonly referred to as water hyacinth, is an invasive aquatic plant that has not undergone comprehensive research about its possible medicinal properties. The present study aims to utilize its rapidly growing potential for medical purposes. The leaves of Eichhornia crassipes were extracted in a sequential manner using hexane, methanol and water using Soxhlet apparatus. The preliminary phytochemical analysis has confirmed the presence of bioactive phytochemicals in the methanolic extract of E. crassipes leaves. The methanolic extract showed different types of high and low molecular weight compounds by GCMS-LCMS analysis. The GC-HRMS analysis revealed the presence of n-hexadecanoic acid, stigmasta-3,5-diene and vitamin E. The HR-LCMS analysis identified the presence of khivorin, cymarin and salicin using positive electrospray ionization (ESI) mode and rhoifolin and digitoxin using negative ESI mode. The isolated and identified compounds in the crude extract exhibit following bioactivities like antimicrobial, antidiabetic, hypocholesterolemic, antioxidant, anti-inflammatory and cytotoxic effects. The extract exhibited cytotoxic effect in the experiments against MCF7 breast cancer cell line, resulting in a reduction in cell viability to 48.29 1.39% with an IC50 value of 770.90 g/mL. Further, studies on DNA ladder assay demonstrated that the cytotoxic effect of extract is due to DNA fragmentation and alteration of DNA properties.},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
Eichhornia crassipes, commonly referred to as water hyacinth, is an invasive aquatic plant that has not undergone comprehensive research about its possible medicinal properties. The present study aims to utilize its rapidly growing potential for medical purposes. The leaves of Eichhornia crassipes were extracted in a sequential manner using hexane, methanol and water using Soxhlet apparatus. The preliminary phytochemical analysis has confirmed the presence of bioactive phytochemicals in the methanolic extract of E. crassipes leaves. The methanolic extract showed different types of high and low molecular weight compounds by GCMS-LCMS analysis. The GC-HRMS analysis revealed the presence of n-hexadecanoic acid, stigmasta-3,5-diene and vitamin E. The HR-LCMS analysis identified the presence of khivorin, cymarin and salicin using positive electrospray ionization (ESI) mode and rhoifolin and digitoxin using negative ESI mode. The isolated and identified compounds in the crude extract exhibit following bioactivities like antimicrobial, antidiabetic, hypocholesterolemic, antioxidant, anti-inflammatory and cytotoxic effects. The extract exhibited cytotoxic effect in the experiments against MCF7 breast cancer cell line, resulting in a reduction in cell viability to 48.29 1.39% with an IC50 value of 770.90 g/mL. Further, studies on DNA ladder assay demonstrated that the cytotoxic effect of extract is due to DNA fragmentation and alteration of DNA properties.
5.
Pavithra, S.; Kathyayani, D.; Rao, H. N.; Soundarya, T. L.; Krishna, B. S.; Nagaraju, G.
In: Solid State Communications, vol. 400, 2025, ISBN: 00381098 (ISSN), (0).
@article{424,
title = {Influence of Sodium lauryl sulphate as surfactant on structural, morphological, electrical, and biological properties on Polypyrrole/CeO2 composites},
author = {S. Pavithra and D. Kathyayani and H. N. Rao and T. L. Soundarya and B. S. Krishna and G. Nagaraju},
url = {https://www.sciencedirect.com/science/article/abs/pii/S0038109825000936?via%3Dihub},
doi = {10.1016/j.ssc.2025.115918},
isbn = {00381098 (ISSN)},
year = {2025},
date = {2025-01-01},
journal = {Solid State Communications},
volume = {400},
publisher = {Elsevier Ltd},
abstract = {Polypyrrole (PPY) was synthesized using ferric chloride as an oxidant, a surfactant, and a natural directing agent. The synthesized samples—PPY-1, PPY/CeO2-1, and PPY/CeO2-2 were characterized using FTIR, SEM, XRD, EDX, and TGA. FTIR analysis confirmed the presence of key functional groups, while XRD revealed characteristic peaks in the 20°–26° range, further validating composite formation. TGA enhanced thermal stability in PPY/CeO2 composites, reinforcing their nanocomposite nature. The polymer composites exhibited high electrical conductivity and improved antibacterial and antimicrobial activity, particularly with the inclusion of a surfactant.},
note = {0},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
Polypyrrole (PPY) was synthesized using ferric chloride as an oxidant, a surfactant, and a natural directing agent. The synthesized samples—PPY-1, PPY/CeO2-1, and PPY/CeO2-2 were characterized using FTIR, SEM, XRD, EDX, and TGA. FTIR analysis confirmed the presence of key functional groups, while XRD revealed characteristic peaks in the 20°–26° range, further validating composite formation. TGA enhanced thermal stability in PPY/CeO2 composites, reinforcing their nanocomposite nature. The polymer composites exhibited high electrical conductivity and improved antibacterial and antimicrobial activity, particularly with the inclusion of a surfactant.
6.
Pavithra, S.; Thejas, R.; Rao, H. N. A.; Krishna, B. S.; Nagaraju, G.
Preparation of polypyrrole by chemical oxidation: applications for sensor studies Journal Article
In: Macromolecular Research, vol. 32, pp. 23-33,, 2024, ISBN: 15985032 (ISSN), (6).
@article{91,
title = {Preparation of polypyrrole by chemical oxidation: applications for sensor studies},
author = {S. Pavithra and R. Thejas and H. N. A. Rao and B. S. Krishna and G. Nagaraju},
doi = {10.1007/s13233-023-00210-0},
isbn = {15985032 (ISSN)},
year = {2024},
date = {2024-01-01},
journal = {Macromolecular Research},
volume = {32},
pages = {23-33,},
publisher = {Polymer Society of Korea},
abstract = {Polypyrrole has gained more attention in conducting polymer science due to its ease of preparation and many advantages. In this article, by chemical oxidation method, three different polypyrroles were prepared using ferric chloride as an oxidant, including surfactant and natural directing agent, and named the samples PPY-1, PPY-2, and PPY-3. XRD, XPS, EDX, FT-IR, SEM, and electrical conductivity was used to characterize the synthesized polypyrrole. XRD confirms that the prepared samples were polypyrrole by showing peaks in the range of 20°–23°. SEM analysis shows that the sizes are between 120 and 180 nm. The present research work is a modest attempt to demonstrate for the first-time detection of hazardous gas using natural directing agent during polypyrrole synthesis. The prepared samples were used for the sensing of butane. PPY-2 shows a high electrical conductivity of 14 × 10–3 S cm−1 and gas sensing with a sensitivity value of 42.03 with lesser response and recovery time. This study reveals the fabrication of low-cost materials for butane sensors. Graphical Abstract: Schematic diagram for the preparation of polypyrrole and its applications. [Figure not available: see fulltext.]. © 2023, The Author(s), under exclusive licence to The Polymer Society of Korea.},
note = {6},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
Polypyrrole has gained more attention in conducting polymer science due to its ease of preparation and many advantages. In this article, by chemical oxidation method, three different polypyrroles were prepared using ferric chloride as an oxidant, including surfactant and natural directing agent, and named the samples PPY-1, PPY-2, and PPY-3. XRD, XPS, EDX, FT-IR, SEM, and electrical conductivity was used to characterize the synthesized polypyrrole. XRD confirms that the prepared samples were polypyrrole by showing peaks in the range of 20°–23°. SEM analysis shows that the sizes are between 120 and 180 nm. The present research work is a modest attempt to demonstrate for the first-time detection of hazardous gas using natural directing agent during polypyrrole synthesis. The prepared samples were used for the sensing of butane. PPY-2 shows a high electrical conductivity of 14 × 10–3 S cm−1 and gas sensing with a sensitivity value of 42.03 with lesser response and recovery time. This study reveals the fabrication of low-cost materials for butane sensors. Graphical Abstract: Schematic diagram for the preparation of polypyrrole and its applications. [Figure not available: see fulltext.]. © 2023, The Author(s), under exclusive licence to The Polymer Society of Korea.
7.
Naik, M. M.; Vinuth, M.; Kumar, V. U.; Hemakumar, K. H.; Preethi, G.; Kumar, M. P.; Nagaraju, G.
A facile green synthesis of nickel ferrite nanoparticles using Tamarindus Indica seeds for magnetic and photocatalytic studies Journal Article
In: Nanotechnology for Environmental Engineering, vol. 8, pp. 143-151,, 2023, ISBN: 23656379 (ISSN), (19).
@article{69,
title = {A facile green synthesis of nickel ferrite nanoparticles using Tamarindus Indica seeds for magnetic and photocatalytic studies},
author = {M. M. Naik and M. Vinuth and V. U. Kumar and K. H. Hemakumar and G. Preethi and M. P. Kumar and G. Nagaraju},
doi = {10.1007/s41204-022-00257-x},
isbn = {23656379 (ISSN)},
year = {2023},
date = {2023-01-01},
journal = {Nanotechnology for Environmental Engineering},
volume = {8},
pages = {143-151,},
publisher = {Springer Science and Business Media Deutschland GmbH},
abstract = {Magnetic NiFe2O4 nanoparticle (NFNPs) were synthesized by the microwave-assisted method using Tamarindus indica seeds as a green reducing agent’ for better readability. The identification of NFNPs was carried out by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), UV–Visible spectroscopy and luminescence techniques. Spinel structure of NFNPs with a single phase has been confirmed by XRD with an average crystallite size of 21 nm. FTIR confirms the presence of tetrahedral and octahedral sites of prepared NFNPs. SEM with EDAX and TEM gives the information of agglomeration of magnetic nanoparticles with elemental composition present in the NFNPs and narrow size distribution of nanoparticles with a particle size of 28 nm. The prepared NFNPs are visible active with band gap of 1.92 eV. NFNPs show effective photocatalytic activity under visible light irradiation towards the degradation of anionic Alizarin red S dye and cationic Methylene Blue dye. NFNPs show good magnetic property in VSM studies. The prepared NFNPs can be useful for wastewater treatment. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.},
note = {19},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
Magnetic NiFe2O4 nanoparticle (NFNPs) were synthesized by the microwave-assisted method using Tamarindus indica seeds as a green reducing agent’ for better readability. The identification of NFNPs was carried out by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), UV–Visible spectroscopy and luminescence techniques. Spinel structure of NFNPs with a single phase has been confirmed by XRD with an average crystallite size of 21 nm. FTIR confirms the presence of tetrahedral and octahedral sites of prepared NFNPs. SEM with EDAX and TEM gives the information of agglomeration of magnetic nanoparticles with elemental composition present in the NFNPs and narrow size distribution of nanoparticles with a particle size of 28 nm. The prepared NFNPs are visible active with band gap of 1.92 eV. NFNPs show effective photocatalytic activity under visible light irradiation towards the degradation of anionic Alizarin red S dye and cationic Methylene Blue dye. NFNPs show good magnetic property in VSM studies. The prepared NFNPs can be useful for wastewater treatment. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
8.
Pillai, R.; Preetha, S.; Narasimhamurthy, B.; Lekshmi, I. C.
Elsevier Ltd, vol. 62, 2022, ISBN: 22147853 (ISSN), (13).
@proceedings{164,
title = {Biosensing of catechol via amperometry using laccase immobilized nickel oxide/graphite modified screen-printed electrodes},
author = {R. Pillai and S. Preetha and B. Narasimhamurthy and I. C. Lekshmi},
doi = {10.1016/j.matpr.2022.03.708},
isbn = {22147853 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Materials Today: Proceedings},
volume = {62},
pages = {5434-5438,},
publisher = {Elsevier Ltd},
abstract = {In the present work, we have developed a modified screen-printed carbon electrode (SPE) based biosensor to detect catechol using nickel oxide/graphite (NiO/G) immobilized with laccase as bio-nanocomposite coating. The laccase immobilized NiO/G composite increased the effective Randles-Sevcik surface area from 0.034 cm2 to 0.083 cm2 compared to bare SPE, resulting in improved electrochemical activity and enhanced reversible catechol oxidation process. Impedance spectroscopic data for the modified SPE (MSPE) showed faster electron transfer than the bare counterpart suggesting the successful immobilization of the bio-nanocomposite onto the electrode surface. Consequently, the cyclic-voltammograms of laccase MSPE exhibited a sharp decrease in the peak-to-peak separation potential and an increase in the current responsiveness. We further, utilized the chronoamperometric method to quantify the catechol detection under optimal conditions, and found a linear biosensor response over the concentration region of 1–100 µM. The sensor's lower detection limit, response time, and sensitivity towards catechol were found to be 65 nM, 3 s, and 1.51 µAµM-1cm−2, respectively. These results suggest that the laccase immobilized NiO/G MSPE as one of the most promising customized electrodes for catechol biosensing. © 2022},
note = {13},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
In the present work, we have developed a modified screen-printed carbon electrode (SPE) based biosensor to detect catechol using nickel oxide/graphite (NiO/G) immobilized with laccase as bio-nanocomposite coating. The laccase immobilized NiO/G composite increased the effective Randles-Sevcik surface area from 0.034 cm2 to 0.083 cm2 compared to bare SPE, resulting in improved electrochemical activity and enhanced reversible catechol oxidation process. Impedance spectroscopic data for the modified SPE (MSPE) showed faster electron transfer than the bare counterpart suggesting the successful immobilization of the bio-nanocomposite onto the electrode surface. Consequently, the cyclic-voltammograms of laccase MSPE exhibited a sharp decrease in the peak-to-peak separation potential and an increase in the current responsiveness. We further, utilized the chronoamperometric method to quantify the catechol detection under optimal conditions, and found a linear biosensor response over the concentration region of 1–100 µM. The sensor's lower detection limit, response time, and sensitivity towards catechol were found to be 65 nM, 3 s, and 1.51 µAµM-1cm−2, respectively. These results suggest that the laccase immobilized NiO/G MSPE as one of the most promising customized electrodes for catechol biosensing. © 2022
9.
Preetha, S.; Ramamoorthy, S.; Pillai, R.; Narasimhamurthy, B.; Lekshmi, I. C.
Elsevier Ltd, vol. 62, 2022, ISBN: 22147853 (ISSN), (5).
@proceedings{173,
title = {Synthesis of rGO-nanoTiO2 composite mixture via ultrasonication assisted mechanical mixing method and their photocatalytic studies},
author = {S. Preetha and S. Ramamoorthy and R. Pillai and B. Narasimhamurthy and I. C. Lekshmi},
doi = {10.1016/j.matpr.2022.04.816},
isbn = {22147853 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Materials Today: Proceedings},
volume = {62},
pages = {5605-5612,},
publisher = {Elsevier Ltd},
abstract = {Reduced graphene oxide - nano TiO2 composite mixture (rGO-nTiO2) was prepared by ultrasonication assisted mechanical mixing method using reduced graphene oxide prepared by green chemical routes, and TiO2 nanocrystals (NCs) synthesized via sol gel technique. UV–Visible absorption and photoluminescence spectroscopy techniques revealed the enhanced light absorption and quenching respectively in rGO-nTiO2 composite system compared to TiO2 NCs. The composite enabled 88% efficiency for Metachrome Yellow dye degradation under natural sunlight as against 80% by TiO2 due to the electron accepting nature of rGO that facilitated larger separation of photogenerated electron–hole pairs, and thereby enhanced their ability for advanced oxidative processes. Structural and morphological evidences from X-ray diffraction, TEM and SEM results confirmed the as-prepared TiO2 as composed of pure anatase phase with tetragonal crystal structure, and largely dispersed in rGO layers in rGO-nTiO2. Based on the scavenger test, it was found that superoxide anion radical played the major role in advanced oxidation of the pollutants, and accordingly the mechanism responsible for the enhanced efficiency is hereby reported. © 2022},
note = {5},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
Reduced graphene oxide - nano TiO2 composite mixture (rGO-nTiO2) was prepared by ultrasonication assisted mechanical mixing method using reduced graphene oxide prepared by green chemical routes, and TiO2 nanocrystals (NCs) synthesized via sol gel technique. UV–Visible absorption and photoluminescence spectroscopy techniques revealed the enhanced light absorption and quenching respectively in rGO-nTiO2 composite system compared to TiO2 NCs. The composite enabled 88% efficiency for Metachrome Yellow dye degradation under natural sunlight as against 80% by TiO2 due to the electron accepting nature of rGO that facilitated larger separation of photogenerated electron–hole pairs, and thereby enhanced their ability for advanced oxidative processes. Structural and morphological evidences from X-ray diffraction, TEM and SEM results confirmed the as-prepared TiO2 as composed of pure anatase phase with tetragonal crystal structure, and largely dispersed in rGO layers in rGO-nTiO2. Based on the scavenger test, it was found that superoxide anion radical played the major role in advanced oxidation of the pollutants, and accordingly the mechanism responsible for the enhanced efficiency is hereby reported. © 2022
10.
Preetha, S.; Lekshmi, I. C.
Institute of Physics, vol. 2332, 2022, ISBN: 17426588 (ISSN), (1).
@proceedings{183,
title = {Bandgap Variations and Photodegradation Efficiency on Inclusion of SiO2in TiO2-rGO Nanocomposite for High Performance Photocatalysis},
author = {S. Preetha and I. C. Lekshmi},
doi = {10.1088/1742-6596/2332/1/012016},
isbn = {17426588 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Journal of Physics: Conference Series},
volume = {2332},
pages = {012016+},
publisher = {Institute of Physics},
abstract = {SiO2 is an excellent support material due to its flexible pore size and can be used as an adsorbent for the removal of toxic materials from water. Nanocrystalline TiO2-rGO is previously reported to show complete photodegradation for azo dyes. In pursuit of enhancing the adsorption capability of the system, we have incorporated SiO2 in TiO2-rGO nanocomposite which has drastically reduced the crystallinity of the matrix. Analysis of the bandgap variations is pursued here, which is crucial for enhanced light absorption and high performance photocatalysis. © Published under licence by IOP Publishing Ltd.},
note = {1},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
SiO2 is an excellent support material due to its flexible pore size and can be used as an adsorbent for the removal of toxic materials from water. Nanocrystalline TiO2-rGO is previously reported to show complete photodegradation for azo dyes. In pursuit of enhancing the adsorption capability of the system, we have incorporated SiO2 in TiO2-rGO nanocomposite which has drastically reduced the crystallinity of the matrix. Analysis of the bandgap variations is pursued here, which is crucial for enhanced light absorption and high performance photocatalysis. © Published under licence by IOP Publishing Ltd.
11.
Preetha, S.; Ramamoorthy, S.; Pillai, R.; Narasimhamurthy, B.; Lekshmi, I. C.
Elsevier Ltd, vol. 62, 2022, ISBN: 22147853 (ISSN), (5).
@proceedings{149,
title = {Influence of Lanthanum‐doping on photocatalytic activity of magnetic BiFeO3 nanocrystals for sunlight driven degradation of metachrome yellow},
author = {S. Preetha and S. Ramamoorthy and R. Pillai and B. Narasimhamurthy and I. C. Lekshmi},
doi = {10.1016/j.matpr.2022.03.608},
isbn = {22147853 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Materials Today: Proceedings},
volume = {62},
pages = {5396-5401,},
publisher = {Elsevier Ltd},
abstract = {In the present work, the structural and photocatalytic activity of BiFeO3 (BFO) and Lanthanum doped BiFeO3 (LBFO; La0.2Bi0.8FeO3) nanocrystals (NCs) towards photodegradation of Metachrome Yellow dye were examined, hitherto unreported in the literature. The bismuth ferrite samples with a prominent rhombohedral phase at room temperature were prepared by sol-gel method, and investigated using multiple structural and spectroscopic tools. La doped BFO was found to be superior in terms of phase formation, photoluminescence quenching and visible light absorption. Further, La doped sample showed higher photodegradation efficiency of 71% compared to 50% by pure BFO NCs for Metachrome Yellow under natural sunlight. The enhanced photocatalytic ability of La doped BFO could be attributed to the increased polarization in the multiferroic oxide that promoted charge separation, besides the small bandgap well into the visible light region of the spectrum and the increased surface hydroxyl groups aiding the redox photodegradation reactions. Vibrating sample magnetometer studies of BFO and LBFO NCs revealed ferrimagnetic nature for the nanomaterials making it a potential photocatalyst for practical applications, as it could be magnetically separated post usage in waterbodies. © 2022},
note = {5},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
In the present work, the structural and photocatalytic activity of BiFeO3 (BFO) and Lanthanum doped BiFeO3 (LBFO; La0.2Bi0.8FeO3) nanocrystals (NCs) towards photodegradation of Metachrome Yellow dye were examined, hitherto unreported in the literature. The bismuth ferrite samples with a prominent rhombohedral phase at room temperature were prepared by sol-gel method, and investigated using multiple structural and spectroscopic tools. La doped BFO was found to be superior in terms of phase formation, photoluminescence quenching and visible light absorption. Further, La doped sample showed higher photodegradation efficiency of 71% compared to 50% by pure BFO NCs for Metachrome Yellow under natural sunlight. The enhanced photocatalytic ability of La doped BFO could be attributed to the increased polarization in the multiferroic oxide that promoted charge separation, besides the small bandgap well into the visible light region of the spectrum and the increased surface hydroxyl groups aiding the redox photodegradation reactions. Vibrating sample magnetometer studies of BFO and LBFO NCs revealed ferrimagnetic nature for the nanomaterials making it a potential photocatalyst for practical applications, as it could be magnetically separated post usage in waterbodies. © 2022
12.
Krupakara, P. V.; Kulkarni, S.
Studies on the stress corrosion behaviour of aluminium 6061 / red mud metal matrix composites Proceedings
Elsevier Ltd, vol. 59, 2022, ISBN: 22147853 (ISSN), (1).
@proceedings{136,
title = {Studies on the stress corrosion behaviour of aluminium 6061 / red mud metal matrix composites},
author = {P. V. Krupakara and S. Kulkarni},
doi = {10.1016/j.matpr.2022.03.427},
isbn = {22147853 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Materials Today: Proceedings},
volume = {59},
pages = {1225-1230,},
publisher = {Elsevier Ltd},
abstract = {Composite materials are very much popular nowadays with respect to their decreased density and improved corrosion and mechanical characteristics. They are in demand in many engineering and manufacturing fields. In this work composite materials of aluminium 6061 reinforced with Two, Four and Six weight percentage of red mud particulates are developed by stir casting process. They were subjected to studies on stress corrosion behaviour in hydrochloric acid and sodium chloride mediums at different temperature and exposure timings with different concentrations using specimens machined from castings as per ASTM standards. In all the mediums it was found that composite materials exhibit improved corrosion resistance on comparison with matrix alloy. Hence composite materials are having extensive applications than matrix alloy. © 2022},
note = {1},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
Composite materials are very much popular nowadays with respect to their decreased density and improved corrosion and mechanical characteristics. They are in demand in many engineering and manufacturing fields. In this work composite materials of aluminium 6061 reinforced with Two, Four and Six weight percentage of red mud particulates are developed by stir casting process. They were subjected to studies on stress corrosion behaviour in hydrochloric acid and sodium chloride mediums at different temperature and exposure timings with different concentrations using specimens machined from castings as per ASTM standards. In all the mediums it was found that composite materials exhibit improved corrosion resistance on comparison with matrix alloy. Hence composite materials are having extensive applications than matrix alloy. © 2022
13.
Preetha, S.; Pillai, R.; Ramamoorthy, S.; Mayeen, A.; Archana, K. M.; Kalarikkal, N.; Narasimhamurthy, B.; Lekshmi, I. C.
TiO2–rGO nanocomposites with high rGO content and luminescence quenching through green redox synthesis Journal Article
In: Surfaces and Interfaces, vol. 30, pp. 101812+, 2022, ISBN: 24680230 (ISSN), (9).
@article{126,
title = {TiO2–rGO nanocomposites with high rGO content and luminescence quenching through green redox synthesis},
author = {S. Preetha and R. Pillai and S. Ramamoorthy and A. Mayeen and K. M. Archana and N. Kalarikkal and B. Narasimhamurthy and I. C. Lekshmi},
doi = {10.1016/j.surfin.2022.101812},
isbn = {24680230 (ISSN)},
year = {2022},
date = {2022-01-01},
journal = {Surfaces and Interfaces},
volume = {30},
pages = {101812+},
publisher = {Elsevier B.V.},
abstract = {We developed TiO2–rGO nanocomposites with high exfoliated rGO content upto 47.1% (TG4) by weight hitherto not reported, through green redox synthesis. Progressive reduction of TiO2 nanocrystal size and their in situ intercalation occurred on increasing rGO via one pot synthesis, not reported previously and forming highly stable Ti–O–C bonds. With increase in rGO content, the exfoliation in the nanocomposite was also limited to single-few layered graphene oxide sheets through use of ascorbic acid avoiding restacking, and thereby the recombination of photogenerated carriers. TG4 showed 50% photoluminescence (PL) quenching indicating long-lived electron transfer state with rGO and apparent rate of nonradiative excited state decay of 1.15 × 108 s−1. Details of lattice orientation, Raman spectra, electronic states and PL lifetime decay are discussed to elucidate effective charge carrier separation in the nanocomposite. Near complete photodegradation of Alizarin Yellow GG azo dye, an industrial pollutant, could be obtained under direct sunlight using TG4 as catalyst. © 2022},
note = {9},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
We developed TiO2–rGO nanocomposites with high exfoliated rGO content upto 47.1% (TG4) by weight hitherto not reported, through green redox synthesis. Progressive reduction of TiO2 nanocrystal size and their in situ intercalation occurred on increasing rGO via one pot synthesis, not reported previously and forming highly stable Ti–O–C bonds. With increase in rGO content, the exfoliation in the nanocomposite was also limited to single-few layered graphene oxide sheets through use of ascorbic acid avoiding restacking, and thereby the recombination of photogenerated carriers. TG4 showed 50% photoluminescence (PL) quenching indicating long-lived electron transfer state with rGO and apparent rate of nonradiative excited state decay of 1.15 × 108 s−1. Details of lattice orientation, Raman spectra, electronic states and PL lifetime decay are discussed to elucidate effective charge carrier separation in the nanocomposite. Near complete photodegradation of Alizarin Yellow GG azo dye, an industrial pollutant, could be obtained under direct sunlight using TG4 as catalyst. © 2022
14.
Padmavathy, N.; Murthy, B. N.; Hemakumar, K. H.
IOP Publishing Ltd, vol. 2070, 2021, ISBN: 17426588 (ISSN), (5).
@proceedings{145,
title = {Direct sunlight driven photocatalytic degradation of hazardous organic dyes using TiO2-NiO nanocomposite p-n junction},
author = {N. Padmavathy and B. N. Murthy and K. H. Hemakumar},
doi = {10.1088/1742-6596/2070/1/012044},
isbn = {17426588 (ISSN)},
year = {2021},
date = {2021-01-01},
journal = {Journal of Physics: Conference Series},
volume = {2070},
pages = {012044+},
publisher = {IOP Publishing Ltd},
abstract = {TiO2 is stable and nontoxic, an effective, low cost, semiconductor photo catalyst to degrade most of the organic pollutants. Nevertheless, the practical application of TiO2 are limited due to two important reasons, while one of the reasons is rapid recombination of electron and hole pair and other one is larger band gap 3.2ev,which permits to absorb 3-4% of solar energy. To enhance photocatalytic activity, several TiO2- metal oxide composites have been used. Due to their electron hole separation ability p-n junction, type semiconductor has become more focused in the last few years. TiO2-NiO nanocomposite is one such catalyst; the presence of NiO facilitates the separation of the hole and the electron pair and encourages the interfacial charge transfer; which facilitates TiO2-NiO a good photocatalyst under direct sunlight. The objective of the study is to synthesise nanocomposite of different mole ratios of NiO and TiO2, to investigate the physicochemical properties such as XRD for phase and purity test, SEM -EDX for morphology and percentage elemental composition, UVDRS for band gap analysis. Photocatalytic activity of TiO2-NiO p-n junction nano structures experiments were carried out under direct sunlight in different systems; using aqueous solution of the dye with effect of pH, concentration of dye, catalyst loading and time on degradation of the organic dye were studied. With increasing the concentration of NiO in to TiO2 -NiO composite increases the photocatalytic activity due to narrowing of the band gap attributed to interfacial charge transfer or higher hole mobility. © Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence.},
note = {5},
keywords = {CHEM},
pubstate = {published},
tppubtype = {proceedings}
}
TiO2 is stable and nontoxic, an effective, low cost, semiconductor photo catalyst to degrade most of the organic pollutants. Nevertheless, the practical application of TiO2 are limited due to two important reasons, while one of the reasons is rapid recombination of electron and hole pair and other one is larger band gap 3.2ev,which permits to absorb 3-4% of solar energy. To enhance photocatalytic activity, several TiO2- metal oxide composites have been used. Due to their electron hole separation ability p-n junction, type semiconductor has become more focused in the last few years. TiO2-NiO nanocomposite is one such catalyst; the presence of NiO facilitates the separation of the hole and the electron pair and encourages the interfacial charge transfer; which facilitates TiO2-NiO a good photocatalyst under direct sunlight. The objective of the study is to synthesise nanocomposite of different mole ratios of NiO and TiO2, to investigate the physicochemical properties such as XRD for phase and purity test, SEM -EDX for morphology and percentage elemental composition, UVDRS for band gap analysis. Photocatalytic activity of TiO2-NiO p-n junction nano structures experiments were carried out under direct sunlight in different systems; using aqueous solution of the dye with effect of pH, concentration of dye, catalyst loading and time on degradation of the organic dye were studied. With increasing the concentration of NiO in to TiO2 -NiO composite increases the photocatalytic activity due to narrowing of the band gap attributed to interfacial charge transfer or higher hole mobility. © Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence.
15.
Vinuth, M.; Naik, Madhukara; Karthik, K.; Naik, H. S.; Hemakumar, K. H.
Detailed study on reduction of hazardous Cr(VI) at acidic pH using modified montmorillonite Fe(II)-Mt under ambient conditions Journal Article
In: Research on Chemical Intermediates, vol. 45, pp. 2357-2368,, 2019, ISBN: 09226168 (ISSN), (8).
@article{247,
title = {Detailed study on reduction of hazardous Cr(VI) at acidic pH using modified montmorillonite Fe(II)-Mt under ambient conditions},
author = {M. Vinuth and Madhukara Naik and K. Karthik and H. S. Naik and K. H. Hemakumar},
doi = {10.1007/s11164-019-03739-x},
isbn = {09226168 (ISSN)},
year = {2019},
date = {2019-01-01},
journal = {Research on Chemical Intermediates},
volume = {45},
pages = {2357-2368,},
publisher = {Springer Netherlands},
abstract = {Contamination of groundwater and soil by high levels of hexavalent chromium directly affects the environment and human health as a serious pollutant. Remediation by reduction, i.e., Cr(VI) → Cr(III), using a variety of reducing agents and/or processes has been explored for many years. In the present study, application of Fe(II)-Montmorillonite [a dioctahedral smectite, Fe(II)-Mt] containing interlayer Fe(II) ions as an environmentally benign clay mineral for reduction of Cr(VI) in acidic pH from aqueous solution was investigated. Fe(II)-Mt was reacted at stoichiometric excess [Fe(II)-Mt: 0.32 g; Cr(VI): 1 mM, 100 mL] in K2Cr2O7 solution at pH of 5.5 and 3.0. The decrease of Cr(VI) was monitored spectrophotometrically, and the results were corrected for the anion exclusion effect, i.e., the electrostatic interaction of HCrO4− ions with the negatively charged surface of the clay mineral. Stoichiometric reduction of Cr(VI) was achieved in short time; at pH 5.5, 20 % reduction was achieved in the first 10 min, after which the reduction proceeded gradually to consume all of the interlayer Fe(II) ions at about 6 h. On the other hand, at pH 3.0, the reaction completed in about 15 min. Moreover, Fe(II)-Mt clay mineral can be conveniently prepared and handled in large amounts, making this method feasible even for remediation of Cr(VI) contamination over large areas in real applications. © 2019, Springer Nature B.V.},
note = {8},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
Contamination of groundwater and soil by high levels of hexavalent chromium directly affects the environment and human health as a serious pollutant. Remediation by reduction, i.e., Cr(VI) → Cr(III), using a variety of reducing agents and/or processes has been explored for many years. In the present study, application of Fe(II)-Montmorillonite [a dioctahedral smectite, Fe(II)-Mt] containing interlayer Fe(II) ions as an environmentally benign clay mineral for reduction of Cr(VI) in acidic pH from aqueous solution was investigated. Fe(II)-Mt was reacted at stoichiometric excess [Fe(II)-Mt: 0.32 g; Cr(VI): 1 mM, 100 mL] in K2Cr2O7 solution at pH of 5.5 and 3.0. The decrease of Cr(VI) was monitored spectrophotometrically, and the results were corrected for the anion exclusion effect, i.e., the electrostatic interaction of HCrO4− ions with the negatively charged surface of the clay mineral. Stoichiometric reduction of Cr(VI) was achieved in short time; at pH 5.5, 20 % reduction was achieved in the first 10 min, after which the reduction proceeded gradually to consume all of the interlayer Fe(II) ions at about 6 h. On the other hand, at pH 3.0, the reaction completed in about 15 min. Moreover, Fe(II)-Mt clay mineral can be conveniently prepared and handled in large amounts, making this method feasible even for remediation of Cr(VI) contamination over large areas in real applications. © 2019, Springer Nature B.V.
16.
Swamy, M. M.; Nagabhushana, B. M.; Krishna, R. H.; Kottam, N.; Raveendra, R. S.; Prashanth, P. A.
Fast adsorptive removal of methylene blue dye from aqueous solution onto a wild carrot flower activated carbon: Isotherms and kinetics studies Journal Article
In: Desalination and Water Treatment, vol. 71, pp. 399-405,, 2017, ISBN: 19443994 (ISSN), (34).
@article{270,
title = {Fast adsorptive removal of methylene blue dye from aqueous solution onto a wild carrot flower activated carbon: Isotherms and kinetics studies},
author = {M. M. Swamy and B. M. Nagabhushana and R. H. Krishna and N. Kottam and R. S. Raveendra and P. A. Prashanth},
doi = {10.5004/dwt.2017.20520},
isbn = {19443994 (ISSN)},
year = {2017},
date = {2017-01-01},
journal = {Desalination and Water Treatment},
volume = {71},
pages = {399-405,},
publisher = {Desalination Publications},
abstract = {In the present study, adsorption of methylene blue (MB) dye from aqueous solution on to a wild carrot flower activated carbon (WCFAC) as a potential adsorbent was investigated. No attempt has been made in the past on WCFAC and it also finds application in reducing the population of this poisonous weed. WCFAC was prepared using simple chemical activation method and MB dye adsorption was studied by batch adsorption experiments. The effects of various parameters like dosage effect, effect of pH, initial concentration of the dye and contact time on the adsorption capacity of MB dye on WCFAC are reported. It was found that, maximum adsorption (~88%) was observed at pH 6 with a good sorption capacity (~21 mg/g) of dye. The adsorption isotherms are analyzed by Langmuir and Freundlich models. The sorption data were better fitted by the Freundlich isotherm model as evident from the R2 value 0.940. Adsorption kinetics was performed and obeys pseudo-second-order kinetic model (R2 at 0.9325). The zero point charge for the WCFAC was found to be 4.9 pH. pH optimization studies show that the favorable adsorption range ~4-6 pH. Experimental and kinetic results reveal that WCFAC is a potential adsorbent for the adsorption of MB dye from aqueous solution. © 2017 Desalination Publications. All rights reserved.},
note = {34},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
In the present study, adsorption of methylene blue (MB) dye from aqueous solution on to a wild carrot flower activated carbon (WCFAC) as a potential adsorbent was investigated. No attempt has been made in the past on WCFAC and it also finds application in reducing the population of this poisonous weed. WCFAC was prepared using simple chemical activation method and MB dye adsorption was studied by batch adsorption experiments. The effects of various parameters like dosage effect, effect of pH, initial concentration of the dye and contact time on the adsorption capacity of MB dye on WCFAC are reported. It was found that, maximum adsorption (~88%) was observed at pH 6 with a good sorption capacity (~21 mg/g) of dye. The adsorption isotherms are analyzed by Langmuir and Freundlich models. The sorption data were better fitted by the Freundlich isotherm model as evident from the R2 value 0.940. Adsorption kinetics was performed and obeys pseudo-second-order kinetic model (R2 at 0.9325). The zero point charge for the WCFAC was found to be 4.9 pH. pH optimization studies show that the favorable adsorption range ~4-6 pH. Experimental and kinetic results reveal that WCFAC is a potential adsorbent for the adsorption of MB dye from aqueous solution. © 2017 Desalination Publications. All rights reserved.
17.
Sheshadri, S. N.; Nagendra, P.; Siddaraju, B. P.; Hemakumar, K. H.; Byrappa, K.; Lokanath, N. K.; Kumar, Madan
Crystal structure of [2-hydroxy-2-(3-methoxyphenyl)cyclohexyl]methyldimethylammonium benzoate Journal Article
In: Acta Crystallographica Section E: Crystallographic Communications, vol. 71, pp. o864-o865,, 2015, ISBN: 20569890 (ISSN), (0).
@article{303,
title = {Crystal structure of [2-hydroxy-2-(3-methoxyphenyl)cyclohexyl]methyldimethylammonium benzoate},
author = {S. N. Sheshadri and P. Nagendra and B. P. Siddaraju and K. H. Hemakumar and K. Byrappa and N. K. Lokanath and Madan Kumar},
doi = {10.1107/S2056989015019362},
isbn = {20569890 (ISSN)},
year = {2015},
date = {2015-01-01},
journal = {Acta Crystallographica Section E: Crystallographic Communications},
volume = {71},
pages = {o864-o865,},
publisher = {International Union of Crystallography},
abstract = {The title compound, C16H26NO2 +·C7H5O2-, is a benzoate salt of the painkiller Tramadol. The six-membered cyclohexane ring of the cation adopts a slightly distorted chair conformation and carries OH and 3-methoxyphenyl substituents at the 2-position and a protonated methylazaniumylmethyl group at the 3-position. In addition, a weak intramolecular C - H⋯O hydrogen bond is observed in the cation. In the crystal, weak O - H⋯O, N - H⋯O and C - H⋯O hydrogen bonds link the components into chains along [010]. A C - H⋯π contact is also observed.},
note = {0},
keywords = {CHEM},
pubstate = {published},
tppubtype = {article}
}
The title compound, C16H26NO2 +·C7H5O2-, is a benzoate salt of the painkiller Tramadol. The six-membered cyclohexane ring of the cation adopts a slightly distorted chair conformation and carries OH and 3-methoxyphenyl substituents at the 2-position and a protonated methylazaniumylmethyl group at the 3-position. In addition, a weak intramolecular C - H⋯O hydrogen bond is observed in the cation. In the crystal, weak O - H⋯O, N - H⋯O and C - H⋯O hydrogen bonds link the components into chains along [010]. A C - H⋯π contact is also observed.
