Dr. Supratim Biswas - Profile on Academia.edu (original) (raw)

Uploads

Papers by Dr. Supratim Biswas

In vitro & in vivo correlation of release behavior of andrographolide from silica and PEG assisted silica gel matrix

Colloids and Surfaces A: Physicochemical and Engineering Aspects, Aug 5, 2014

Silica xerogel and its PEG assisted derivatives were prepared by sol–gel method for controlled re... more Silica xerogel and its PEG assisted derivatives were prepared by sol–gel method for controlled release of andrographolide. In vitro and in vivo release of andrographolide from the nano porous silica as well as PEG modified silica matrix were studied. Drug release from the matrix increased with increasing percentage of PEG and followed a biphasic pattern. The in vitro release profile followed zero order kinetics with erosion of the matrix for the first six hours and higuchi model with the diffusion mechanism for rest of the time period. Pharmacokinetic data revealed sustained release of the drug from silica–drug composite with higher elimination t1/2 than the pure drug. For all the formulations Level A in vitro-in vivo correlation (IVIVC) was established with (R2) > 0.98. Histology of different organs was carried out following in vivo administration of the drug-carrier composite. The histological examination demonstrated absence of any inflammatory or degenerative response with the formulations. Fourier transform infrared (FTIR) data revealed the coexistence of andrographolide in the silica matrix. Transmission electron microscope (TEM) images also unfold the repose matrix structure in PEG assisted derivatives than the pure matrix. This study discloses that silica gel and PEG assisted derivatives could be used as a biocompatible and sustained release device for andrographolide.

Extraction of metals (Ni, Co) from chromite overburden of Sukinda mines of Orissa, India, with th... more Extraction of metals (Ni, Co) from chromite overburden of Sukinda mines of Orissa, India, with the culture filtrate of Aspergillus niger was studied. Results showed that the amounts of metals leached varied directly with reaction temperature and period of fermentation. The culture filtrate was analyzed for citric and oxalic acids, and contained only oxalic acid-the concentration of which increased with time. Although this acid played the major role in leaching of metals, other unidentified metabolites present in the culture filtrate influenced the dissolution of the metals significantly. Maximum recovery of metals from raw and roasted ore samples was achieved at 80°C with the 21-day culture filtrate containing the highest amount of oxalic acid. Under identical experimental conditions, much higher amounts of the metals were leached from roasted ore. Microstructures of the ore particles were studied by scanning electron microscopy and transmission electron microscopy; the bonding behaviors of metal compounds were identified by Fourier transform infrared spectroscopy which showed that the metals were leached after chelation with oxalic acid.

Leaching of nickel and cobalt from two physical grades (S1, 125-190 µm, coarser and S3, 53-75 µm,... more Leaching of nickel and cobalt from two physical grades (S1, 125-190 µm, coarser and S3, 53-75 µm, finer) of chromite overburden was achieved by treating the overburden (2% pulp density) with 21-d culture filtrate of an Aspergillus niger strain grown in sucrose medium. Metal dissolution increases with ore roasting at 600 • C and decreasing particle size due to the alteration of microstructural properties involving the conversion of goethite to hematite and the increase in surface area and porosity as evident from X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (DT-TGA), and field emission scanning electron microscopy (FESEM). About 65% Ni and 59% Co were recovered from the roasted S3 ore employing bioleaching against 26.87% Ni and 31.3% Co using an equivalent amount of synthetic oxalic acid under identical conditions. The results suggest that other fungal metabolites in the culture filtrate played a positive role in the bioleaching process, making it an efficient green approach in Ni and Co recovery from lateritic chromite overburden.

Objective:The objective of the paper is to study the carrier mediated sustained delivery of a mul... more Objective:The objective of the paper is to study the carrier mediated sustained delivery of a multi-potent herb (Andrographis paniculata) and also to investigate the anti-microbial potency of the herbal extract in gel entrapped condition. Methods:Silica gel was prepared in room temperature. Extraction of Andrographis paniculata is done in a sohxlet apparatus using methanol as the solvent. The extract is successfully entrapped in the silica gel which is confirmed by FTIR analysis. Gel entrapped herbal extracts are released in PBS buffer of neutral pH solution and the release of herbal extract is being obtained from UV-visible spectroscopic analysis. Results:TEM image revealed porous nature and also the pore sizes of the silica gel. 21% of the herbal extract was released in 168 hours. MIC values of the extract were determined against bacteria. Kirby Bauer sensitivity test was performed with gel entrapped form and it was compared with crude extract and it is seen that the MIC value of the extract is less when in entrapped condition than the crude one Conclusion:Thus we can conclude from the results that sol gel derived silica gel can be considered as controlled drug delivery system and enable increased shelf life of entrapped drug.. ABSTRACT 1 2 2 2 3 †

Low-grade nickeliferous lateritic ore from Sukinda region of Orissa, India, was subjected to bioh... more Low-grade nickeliferous lateritic ore from Sukinda region of Orissa, India, was subjected to biohydrometallurgical treatment for the extraction of nickel and cobalt. The mineralogical studies reveal that nickel is entrapped in goethite matrix while cobalt is associated with the manganese phase. Aspergillus wentii NCIM 667, a citric acid producing fungal strain, was used for direct (one step and two step) and indirect (using culture filtrate) leaching of the metals under different conditions. The effect of varying pulp density (2%, 5%, 8%) and culture medium composition (viz. molasses and sucrose media) was investigated and the leaching conditions optimized. It was found that a maximum of 49.29% Ni and 35.18% Co could be recovered from the heat-treated lateritic chromite overburden by the culture filtrate bioleaching at 80°C with 2% pulp density.

BACKGROUND: Leaching kinetics of the roasted (at 600 • C) chromite overburden of Sukinda mines Or... more BACKGROUND: Leaching kinetics of the roasted (at 600 • C) chromite overburden of Sukinda mines Orissa, India, was studied with optimized data generated through response surface methodology (RSM) coupled with Box-Behnken design (BBD). The effects of oxalic, citric and gluconic acid concentration (50-150 mmol L −1 ), reaction temperature (60 • to 80 • C) and period (up to 3 h) on metal (nickel and cobalt) dissolution were examined. RESULTS: Extraction of nickel and cobalt to the extent of 63.61% and 44.33%, respectively, was achieved using 150 mmol L −1 oxalic acid at 80 • C in 3 h; compared with other acids, oxalic acid leached more of the metals. Associated apparent activation energy for Ni was 74 kJ mol −1 , and that for cobalt was 84.37 kJ mol −1 during the first hour, and 80.99 kJ mol −1 for the remaining period since cobalt leaching followed biphasic kinetics.

The synthesis of metal nanoparticles is a growing area for research due to its potentiality in th... more The synthesis of metal nanoparticles is a growing area for research due to its potentiality in the application and development of advanced technologies. In general, nanoparticles are synthesized by using chemical methods which are not eco-friendly. Here, we have used a fast, convenient and environment-friendly method for the synthesis of silver nanoparticles by reducing silver nitrate with fruit extract of grape (Vitis vinifera). Characterization of the metallic nanoparticles was done by UV-Vis Spectroscopy, Dynamic Light Scattering (DLS) and Energy Dispersive X-ray Spectroscopy (EDX). The particle size and lattice image of the silver nanoparticles was studied by Transmission Electron Microscopy (TEM). The antibacterial activity of these nanoparticles was studied against Bacillus subtilis and Escherichia coli. Growth curves of bacteria in presence of silver nanoparticles showed inhibition of growth suggesting antibacterial property of the nanoparticles.

Encapsulation of herbal values into bio-compatible porous silica gel has been attempted with the ... more Encapsulation of herbal values into bio-compatible porous silica gel has been attempted with the aim of developing a sustainable, efficient, eco-friendly and controlled drug delivery system using greener traditional alternatives. Aqueous extraction of Andrographis paniculata and entrapment of the same into silica gel has been studied. FTIR peaks prove the presence of herbal values into the silica matrix. 27% of the herbal extract is released in the Phosphate Buffer Saline (PBS) buffer in a period of 240 hours.

This review aims at compiling the different mutational changes undergone by the factor VIII gene ... more This review aims at compiling the different mutational changes undergone by the factor VIII gene leading to hemophilia A. It has been difficult to characterize completely a genetic disorder like hemophilia A where the gene of concerns is large, its tissue-specific expression, and all affected individuals have different mutational patterns. In this review, point mutational, insertional and deletional patterns are sited. The data are collected from all round the world, although "Western" sources are predominate.

In vitro & in vivo correlation of release behavior of andrographolide from silica and PEG assisted silica gel matrix

Colloids and Surfaces A: Physicochemical and Engineering Aspects, Aug 5, 2014

Silica xerogel and its PEG assisted derivatives were prepared by sol–gel method for controlled re... more Silica xerogel and its PEG assisted derivatives were prepared by sol–gel method for controlled release of andrographolide. In vitro and in vivo release of andrographolide from the nano porous silica as well as PEG modified silica matrix were studied. Drug release from the matrix increased with increasing percentage of PEG and followed a biphasic pattern. The in vitro release profile followed zero order kinetics with erosion of the matrix for the first six hours and higuchi model with the diffusion mechanism for rest of the time period. Pharmacokinetic data revealed sustained release of the drug from silica–drug composite with higher elimination t1/2 than the pure drug. For all the formulations Level A in vitro-in vivo correlation (IVIVC) was established with (R2) > 0.98. Histology of different organs was carried out following in vivo administration of the drug-carrier composite. The histological examination demonstrated absence of any inflammatory or degenerative response with the formulations. Fourier transform infrared (FTIR) data revealed the coexistence of andrographolide in the silica matrix. Transmission electron microscope (TEM) images also unfold the repose matrix structure in PEG assisted derivatives than the pure matrix. This study discloses that silica gel and PEG assisted derivatives could be used as a biocompatible and sustained release device for andrographolide.

Extraction of metals (Ni, Co) from chromite overburden of Sukinda mines of Orissa, India, with th... more Extraction of metals (Ni, Co) from chromite overburden of Sukinda mines of Orissa, India, with the culture filtrate of Aspergillus niger was studied. Results showed that the amounts of metals leached varied directly with reaction temperature and period of fermentation. The culture filtrate was analyzed for citric and oxalic acids, and contained only oxalic acid-the concentration of which increased with time. Although this acid played the major role in leaching of metals, other unidentified metabolites present in the culture filtrate influenced the dissolution of the metals significantly. Maximum recovery of metals from raw and roasted ore samples was achieved at 80°C with the 21-day culture filtrate containing the highest amount of oxalic acid. Under identical experimental conditions, much higher amounts of the metals were leached from roasted ore. Microstructures of the ore particles were studied by scanning electron microscopy and transmission electron microscopy; the bonding behaviors of metal compounds were identified by Fourier transform infrared spectroscopy which showed that the metals were leached after chelation with oxalic acid.

Leaching of nickel and cobalt from two physical grades (S1, 125-190 µm, coarser and S3, 53-75 µm,... more Leaching of nickel and cobalt from two physical grades (S1, 125-190 µm, coarser and S3, 53-75 µm, finer) of chromite overburden was achieved by treating the overburden (2% pulp density) with 21-d culture filtrate of an Aspergillus niger strain grown in sucrose medium. Metal dissolution increases with ore roasting at 600 • C and decreasing particle size due to the alteration of microstructural properties involving the conversion of goethite to hematite and the increase in surface area and porosity as evident from X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (DT-TGA), and field emission scanning electron microscopy (FESEM). About 65% Ni and 59% Co were recovered from the roasted S3 ore employing bioleaching against 26.87% Ni and 31.3% Co using an equivalent amount of synthetic oxalic acid under identical conditions. The results suggest that other fungal metabolites in the culture filtrate played a positive role in the bioleaching process, making it an efficient green approach in Ni and Co recovery from lateritic chromite overburden.

Objective:The objective of the paper is to study the carrier mediated sustained delivery of a mul... more Objective:The objective of the paper is to study the carrier mediated sustained delivery of a multi-potent herb (Andrographis paniculata) and also to investigate the anti-microbial potency of the herbal extract in gel entrapped condition. Methods:Silica gel was prepared in room temperature. Extraction of Andrographis paniculata is done in a sohxlet apparatus using methanol as the solvent. The extract is successfully entrapped in the silica gel which is confirmed by FTIR analysis. Gel entrapped herbal extracts are released in PBS buffer of neutral pH solution and the release of herbal extract is being obtained from UV-visible spectroscopic analysis. Results:TEM image revealed porous nature and also the pore sizes of the silica gel. 21% of the herbal extract was released in 168 hours. MIC values of the extract were determined against bacteria. Kirby Bauer sensitivity test was performed with gel entrapped form and it was compared with crude extract and it is seen that the MIC value of the extract is less when in entrapped condition than the crude one Conclusion:Thus we can conclude from the results that sol gel derived silica gel can be considered as controlled drug delivery system and enable increased shelf life of entrapped drug.. ABSTRACT 1 2 2 2 3 †

Low-grade nickeliferous lateritic ore from Sukinda region of Orissa, India, was subjected to bioh... more Low-grade nickeliferous lateritic ore from Sukinda region of Orissa, India, was subjected to biohydrometallurgical treatment for the extraction of nickel and cobalt. The mineralogical studies reveal that nickel is entrapped in goethite matrix while cobalt is associated with the manganese phase. Aspergillus wentii NCIM 667, a citric acid producing fungal strain, was used for direct (one step and two step) and indirect (using culture filtrate) leaching of the metals under different conditions. The effect of varying pulp density (2%, 5%, 8%) and culture medium composition (viz. molasses and sucrose media) was investigated and the leaching conditions optimized. It was found that a maximum of 49.29% Ni and 35.18% Co could be recovered from the heat-treated lateritic chromite overburden by the culture filtrate bioleaching at 80°C with 2% pulp density.

BACKGROUND: Leaching kinetics of the roasted (at 600 • C) chromite overburden of Sukinda mines Or... more BACKGROUND: Leaching kinetics of the roasted (at 600 • C) chromite overburden of Sukinda mines Orissa, India, was studied with optimized data generated through response surface methodology (RSM) coupled with Box-Behnken design (BBD). The effects of oxalic, citric and gluconic acid concentration (50-150 mmol L −1 ), reaction temperature (60 • to 80 • C) and period (up to 3 h) on metal (nickel and cobalt) dissolution were examined. RESULTS: Extraction of nickel and cobalt to the extent of 63.61% and 44.33%, respectively, was achieved using 150 mmol L −1 oxalic acid at 80 • C in 3 h; compared with other acids, oxalic acid leached more of the metals. Associated apparent activation energy for Ni was 74 kJ mol −1 , and that for cobalt was 84.37 kJ mol −1 during the first hour, and 80.99 kJ mol −1 for the remaining period since cobalt leaching followed biphasic kinetics.

The synthesis of metal nanoparticles is a growing area for research due to its potentiality in th... more The synthesis of metal nanoparticles is a growing area for research due to its potentiality in the application and development of advanced technologies. In general, nanoparticles are synthesized by using chemical methods which are not eco-friendly. Here, we have used a fast, convenient and environment-friendly method for the synthesis of silver nanoparticles by reducing silver nitrate with fruit extract of grape (Vitis vinifera). Characterization of the metallic nanoparticles was done by UV-Vis Spectroscopy, Dynamic Light Scattering (DLS) and Energy Dispersive X-ray Spectroscopy (EDX). The particle size and lattice image of the silver nanoparticles was studied by Transmission Electron Microscopy (TEM). The antibacterial activity of these nanoparticles was studied against Bacillus subtilis and Escherichia coli. Growth curves of bacteria in presence of silver nanoparticles showed inhibition of growth suggesting antibacterial property of the nanoparticles.

Encapsulation of herbal values into bio-compatible porous silica gel has been attempted with the ... more Encapsulation of herbal values into bio-compatible porous silica gel has been attempted with the aim of developing a sustainable, efficient, eco-friendly and controlled drug delivery system using greener traditional alternatives. Aqueous extraction of Andrographis paniculata and entrapment of the same into silica gel has been studied. FTIR peaks prove the presence of herbal values into the silica matrix. 27% of the herbal extract is released in the Phosphate Buffer Saline (PBS) buffer in a period of 240 hours.

This review aims at compiling the different mutational changes undergone by the factor VIII gene ... more This review aims at compiling the different mutational changes undergone by the factor VIII gene leading to hemophilia A. It has been difficult to characterize completely a genetic disorder like hemophilia A where the gene of concerns is large, its tissue-specific expression, and all affected individuals have different mutational patterns. In this review, point mutational, insertional and deletional patterns are sited. The data are collected from all round the world, although "Western" sources are predominate.