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Papers by Debbithi Bera

Journal of Materials Research

Herein, we have demonstrated and compared bimodal strategies towards augmenting the antimicrobial... more Herein, we have demonstrated and compared bimodal strategies towards augmenting the antimicrobial activity of graphene oxide (GO). Among the two modifications viz. through alteration of GO surface functionalities and secondly through surface modification of GO with an ampicillin-based antibacterial ionic liquid (IL), the IL modification was most effective in enhancing the bactericidal effect. pH and the zeta potential values of the nanodispersions support the alteration of surface functionalities of GO by variation in reaction conditions and SEM, XRD, Raman spectra establish the resulting sheet thickness, morphology, stacking and planarity. The surface modification of GO with trihexyltetradecyl phosphonium ampicillin ([TTP][Amp]) IL as indicated by FTIR, SEM, pH and zeta potential measurements imply in nearly five times lower MBC value compared to average MBC value of the four GO variants. Hence, judicious IL modification can be an effective approach towards augmenting antibacterial property of GO for enduring antifouling coatings and membranes.

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences

Proceedings of MOL2NET 2020, International Conference on Multidisciplinary Sciences, 6th edition, 2020

The particles within the nanoregime are quite smaller (100-10,000 times) than human cells but are... more The particles within the nanoregime are quite smaller (100-10,000 times) than human cells but are comparable to that of biomolecules like enzymes and receptors. The nanoparticles smaller than 50 nm can easily pervade into most cells, and those particles smaller than 20 nm can easily escape into the circulation through the blood vessels. Nanoparticles are quite conducive to be fabricated appropriately to serve as a device/vehicles of important therapeutic genes or drugs specifically to the cancer cells avoiding any hazardous effects on the normal cells. This review encompasses the recent investigations employing nanocarriers like liposomes, micelles, carbon nanotubes, dendrimers, nanoshells that has been developed with positive results.The cancer therapeutic agents like Doxorubicin, Paclitaxel, Cystatin ,Small interfering RNA(SiRNAs) are encapsulated within these nanocarriers through the processes of entrapping, covalent binding, encapsulation or adsorption. Furthermore these nanoparticles were conjugated with cancer specific targetic ligands like Folic acid, Monoclonal antibody,Luteinising hormone releasing hormone(LHRH)peptide,etc which enable them to successfully deliver the therapeutic agents to the cancerous cells. Henceforth the development of these smart nanodevices will undoubtedly pave the way for coming up with future novel therapeutic strategies for combating the malignant cells circumventing any adverse side effects on the normal cells.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2020

Using a U-shaped glass tube where one arm contains bi-distilled water and the other arm ethyl alc... more Using a U-shaped glass tube where one arm contains bi-distilled water and the other arm ethyl alcohol (91%) separated by a platinum foil, the generated voltage across two platinum electrodes and a DC power of the order of nanoW were measured. The generated voltage lasted for many hours. The magnitude of both the voltage and power generated increased with vigorous shaking of the alcohol. Considering the absence of any significant quantity of ionic solutes in this system, voltage generation from two different polar liquids separated by a metal separator is an interesting phenomenon in the context of classical electrochemistry and seems to imply some kind of non-ionic conduction. A qualitative explanation of this phenomenon has been offered here based on the principle of Quantum Electrodynamics.

Materials Today Communications, 2021

Abstract Configuring ionic liquids (ILs) to generate synergy or to deliver multiple pharmaceutica... more Abstract Configuring ionic liquids (ILs) to generate synergy or to deliver multiple pharmaceutically active ingredients through a single compound is an emerging area in future medicine where phosphonium ionic liquids (PILs) exhibit potential as antibacterial drugs. Herein, we report the strategic development of two purely ionic mono and bis-PILs based on trihexyltetradecyl phosphonium ([TTP]+) contributing as the cation coupled with monoprotonated fluorescein ([HFl]-) and dianionic fluorescein ([Fl2-]) anions through metathesis reaction. In spite of negligible bactericidal effect of [Fl]2-, the [HFl]- and [Fl2- salts exhibit enhanced and selective bactericidal activity at drastically reduced concentrations. [TTP][HFl] exhibits bactericidal effect at 2 times lower concentration against E. coli and [TTP]2[Fl] at 10 times lower concentrations against S. aureus with respect to the precursor [TTP][Cl]. Docking studies of [TTP][HFl] and [TTP]2[Fl] as well as the precursors with two modelled bacterial cell wall fragments and three RNAs indicate direct correlation between best binding pose and experimentally obtained minimum bactericidal concentrations (MBC). The study suggests the inhibition of peptidoglycan maturation through linkage between phenolate of Fl unit and the D -Ala- D -Ala group of the peptide chain in the cell wall fragment as well as inhibition of RNA/DNA synthesis as probable mechanisms of bacterial cell death. This multistaged cell death mechanism explains the appearance of unexpectedly improved antibacterial activity and selectivity in the mono and bis- phosphonium fluorescein salts. Thus, the results recommend strong potential of the studied PILs to be used as new series of broad spectrum antibacterial agents with reduced risk for development of drug resistant strains.

Colloids and Surfaces B: Biointerfaces, 2021

Biofilm formation on medical implants and devices has been a severe concern that results in their... more Biofilm formation on medical implants and devices has been a severe concern that results in their impaired performance and life-threatening complications. Thus, development of novel functional coatings for infection prone surfaces with biofilm inhibiting characteristics is of prime significance considering the rapid emergence of multidrug resistant bacteria. Herein we present a novel nanocomposite derived from Graphene Oxide (GO) and a newly developed functional Ionic liquid (IL) obtained through a metathesis reaction between a triarylmethane dye hexamethyl pararosaniline chloride or crystal violet (CV) and sodium dodeceyl sulfate (SDS) to yield [CV][DS] (hexamethyl pararosaniline dodecyl sulfate). This highly biocompatible [CV][DS]-GO nanocomposite exhibit more than four times improved antibacterial activity in comparison to bare GO against both gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus). As suggested by XRD, FTIR and UV absorption and SEM results improved activity of [CV][DS]-GO nanocomposite is ascribed to the synergistic effect of reduced nanocomposite sheet thickness, enhanced amphiphilicity imparted by dodecylsulfate (DS), exposed active ArN+ groups of CV and some inherent functionalities of GO. This is also complemented by the ruptured and diffused S. aureus cell walls as observed in bacterial SEM result. In contrast, the nanocomposites of the precursors with GO do not demonstrate any significant antibacterial effect. Coatings developed using GO upon infestation with E. coli revealed significant biofilm formation after 48 and 72 h of incubation while [CV][DS]-GO coated surface demonstrated no colony growth under similar circumstances. Thus, [CV][DS]-GO nanocomposite coatings exhibit excellent resistance to bacterial growth even up to 72 h incubation signifying its bactericidal effect. Therefore, the developed nanocomposite may be considered as one of the improved antibacterial wash resistant coating material for biomedical devices and surfaces susceptible to to biofilm formation.

MOJ Ecology & Environmental Sciences, 2018

Using liposomal membrane of 1, 2-dipalmitoyl-sn -glycero-3- phosphatidyl choline, a well accepted... more Using liposomal membrane of 1, 2-dipalmitoyl-sn -glycero-3- phosphatidyl choline, a well accepted model for biological membrane, we have measured the change in membrane anisotropy due to incorporation of three homoeopathic drugs silicea, sulphur and calc carb and the associated values of change in Van’t Hoff enthalpy have been calculated. Our experimental results reveal that these three homoeopathic drugs affect the membrane anisotropy in different ways and this change depends upon the potency of the medicine.

Journal of Drug Delivery Science and Technology, 2020

This study reports the observed synergy in antimicrobial and anticancer activity of thymoquinone ... more This study reports the observed synergy in antimicrobial and anticancer activity of thymoquinone and piperine, encapsulated in porous guar gum micro-vehicle. Natural therapeutics like piperine and thymoquinone showed less effectivity in human medical trials due to their hydrophobicity leading to poor clinical efficacy. To overcome this problem, we have developed a delivery strategy by using guar gum, a natural biodegradable biopolymer. The successful encapsulation of phytochemicals and the microstructures of gum micro-vehicles were confirmed by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and UV-Vis spectra analysis. We also report here a significant decrease in minimum inhibitory concentration (MIC) value and synergistic bactericidal activity against four different bacterial strains and observed remarkably low median lethal dose (LD50) value against human hepatocellular carcinoma cell lines along with pH-responsive delivery of therapeutic in the case of combinatorial therapy. In our overall study, we analyze and discuss the structure, efficacy, and delivery of our designed natural therapeutic amalgamation to pave the way for augmenting the use of phytochemicals in medical applications.

Proceedings of MOL2NET 2020, International Conference on Multidisciplinary Sciences, 6th edition, 2020

The emergence of natural polymers like gums and mucilages in drug delivery systems has curbed the... more The emergence of natural polymers like gums and mucilages in drug delivery systems has curbed the rampant use of the synthetic materials for therapeutic purposes. Natural excipients offered advantages such as non-toxicity, less cost and abundantly availablity. Aqueous solubility of natural excipients plays an important role in their selection for designing immediate, controlled or sustained release formulations. This review article provides an overview of natural gum, polymers and

Materials Today Communications, 2020

A mechanistic insight into the bioaccesible herbometallic nanodrug as potential dual therapeutic ... more A mechanistic insight into the bioaccesible herbometallic nanodrug as potential dual therapeutic agent Debbethi Bera (Conceptualization) (Resources) (Methodology) (Investigation) (Writing-original draft), Kunal Pal (Investigation)

Ecotoxicology and Environmental Safety, 2020

The ability of P. laurentii strain RY1 to remediate lead (Pb 2+) from water was investigated in b... more The ability of P. laurentii strain RY1 to remediate lead (Pb 2+) from water was investigated in batch and column studies. The lead removal ability of non-viable biomass, non-viable biomass immobilised on agar-agar (biobeads) and agar-agar at different pH was compared in batch studies. It was found that among the three, biobeads have maximum ability to remove Pb 2+ followed by biomass and agar-agar beads. Maximum and almost equal lead removal by biobeads was observed at both neutral and alkaline pH making it a novel and more applicable bioremediator as all other reported bioremediators have a single pH for optimum activity. Studies were performed to determine the optimum conditions for lead removal from aqueous solutions for biobeads. The physical and chemical characterization of the biobeads before and after Pb 2+ biosorption was done by using S.E.M. and F.T.I.R. respectively. The adsorption of Pb 2+ on biobeads obeyed the Langmuir adsorption isotherm and pseudo first order kinetics. These mean that the Pb 2+ binding sites are identical, located on the surface of the adsorbant and the rate of Pb 2+ removal from aqueous solution is directly proportional to the number of Pb 2+ binding sites on the biobeads. The thermodynamics of the biosorption process is also investigated. The binding capacity of the biobeads in batch study was found to be 52.91mg/gm which is higher in comparison to other reported yeast bioremediators. The used biobeads can be desorbed using 0.1(M) CaCl 2. The desorbed biobeads can be used subsequently for several cycles of lead removal making it cost-effective. Column studies were also performed for biobeads with the help of Thomas model for examining its suitability for industrial application. Maximum specific lead uptake of the biobeads when applied in the column was found to be 58.26mg/gm which being promising makes it suitable for application in industries involved in the treatment of wastewater contaminated with high amounts of lead. The high mass transfer coefficient indicate that small sized column can be used effectively to remove high amounts of lead which makes the bioremediation process by the biobeads more economical and advantageous for industrial application. Several factors like effectiveness of the biobeads in Pb 2+ removal at both neutral and alkaline pH, reusability, high mass transfer coefficient , regenerability and high binding capacity makes it a novel versatile, cost-effective and high utility bioremediator. natural sources (bedrock, soil) and industrial emission (Cheng and Hu, 2010). Industries producing lead as waste include pulp and paper industry, tannery, fertilizer and herbicide industries, battery manufacturing industries as well as mining and metallurgical industries (Asuquo et al., 2017).

Colloids and Surfaces B: Biointerfaces, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

RSC Advances, 2018

A single LMW gelator based core–shell hydrogel with dual release kinetics.

Journal of Materials Science: Materials in Electronics, 2018

Under certain conditions, ultra high diluted triturated material achieve nanodimension. This nano... more Under certain conditions, ultra high diluted triturated material achieve nanodimension. This nanoparticle aspect of the materials has been used in various technical applications. The electrical properties of the polymer, Poly (vinylidene fluoride), commonly used as dielectric separator in high charge storage multilayer capacitor, get improved when doped with these triturated material. We have reported here how these effects get further increased by changing the doping concentration. With incorporation of 2 ml of triturated copper acetate salt, there are ~ 14.0, ~ 2.74, ~ 9.0 fold increment in β-phase, dielectric constant and ac conductivity respectively compared to the undoped polymer matrix. This is also associated with significant decrease (~ 66%) in tangent loss. Doping of these nanomaterials in the highly insulating matrix of the polymer is an effective way to fabricate composites with tunable dielectric behavior, making them a promising candidate in electronic industry. A device, using our material as separator have been designed and observed that the charge storing ability of the composite persists for more than 24 h. After 1 h of charging, maximum recorded voltage using our fabricated system is 2.034 V, whereas electrode separator system of commercial Li-polymer ion mobile battery can store 0.566 V.

Homeopathy, 2019

Background For the study of homeopathic medicines in proper perspective, emerging techniques in m... more Background For the study of homeopathic medicines in proper perspective, emerging techniques in material science are being used. Vibrational spectroscopy is one such tool for providing information on different states of hydrogen bonding as an effect of potentization. The associated change in electrical properties is also correlated with this effect. Objective From the vibrational spectra, the changes in hydrogen bonding due to dilution followed by unidirectional vigorous shaking (together termed potentization) of 91% ethanol and two homeopathic medicines Chininum purum and Acidum benzoicum have been studied. The aim was to correlate the result with the change in the electrical properties of the system. Methods Raman spectroscopy was used to study the vibrational spectra. A U-shaped glass tube (electrochemical cell), where one arm contained bi-distilled water and the other arm alcohol/homeopathic medicine (the arms being separated by a platinum foil), was used to measure the voltage ...

Homeopathy : the journal of the Faculty of Homeopathy, May 1, 2018

We report the effects of nanoparticles in homeopathic preparations of copper salts on the electr... more We report the effects of nanoparticles in homeopathic preparations of copper salts on the electrical properties of polymer film. Previous work showed that the incorporation of metal-derived homeopathic medicines increases the dielectric constant and alternating current (AC) conductivity of an electroactive polymer film that is commonly used as a capacitor in the electronic industry.We report here the effect of dilution of one homeopathic medicine, (), at 200C potency on the electrical properties of the polymer film of poly(vinylidene fluoride-co-hexafluoropropylene). 200c was incorporated in the film by the solution casting method. The electrical characteristics were measured at different frequencies using an inductance, capacitance, and resistance meter. Fourier transform infrared spectroscopy (FTIR) was performed to detect phase change in the polymer film due to the incorporation of . Morphology and particle size were studied using field emission scanning electron microscopy (F...

Journal of Materials Research

Herein, we have demonstrated and compared bimodal strategies towards augmenting the antimicrobial... more Herein, we have demonstrated and compared bimodal strategies towards augmenting the antimicrobial activity of graphene oxide (GO). Among the two modifications viz. through alteration of GO surface functionalities and secondly through surface modification of GO with an ampicillin-based antibacterial ionic liquid (IL), the IL modification was most effective in enhancing the bactericidal effect. pH and the zeta potential values of the nanodispersions support the alteration of surface functionalities of GO by variation in reaction conditions and SEM, XRD, Raman spectra establish the resulting sheet thickness, morphology, stacking and planarity. The surface modification of GO with trihexyltetradecyl phosphonium ampicillin ([TTP][Amp]) IL as indicated by FTIR, SEM, pH and zeta potential measurements imply in nearly five times lower MBC value compared to average MBC value of the four GO variants. Hence, judicious IL modification can be an effective approach towards augmenting antibacterial property of GO for enduring antifouling coatings and membranes.

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences

Proceedings of MOL2NET 2020, International Conference on Multidisciplinary Sciences, 6th edition, 2020

The particles within the nanoregime are quite smaller (100-10,000 times) than human cells but are... more The particles within the nanoregime are quite smaller (100-10,000 times) than human cells but are comparable to that of biomolecules like enzymes and receptors. The nanoparticles smaller than 50 nm can easily pervade into most cells, and those particles smaller than 20 nm can easily escape into the circulation through the blood vessels. Nanoparticles are quite conducive to be fabricated appropriately to serve as a device/vehicles of important therapeutic genes or drugs specifically to the cancer cells avoiding any hazardous effects on the normal cells. This review encompasses the recent investigations employing nanocarriers like liposomes, micelles, carbon nanotubes, dendrimers, nanoshells that has been developed with positive results.The cancer therapeutic agents like Doxorubicin, Paclitaxel, Cystatin ,Small interfering RNA(SiRNAs) are encapsulated within these nanocarriers through the processes of entrapping, covalent binding, encapsulation or adsorption. Furthermore these nanoparticles were conjugated with cancer specific targetic ligands like Folic acid, Monoclonal antibody,Luteinising hormone releasing hormone(LHRH)peptide,etc which enable them to successfully deliver the therapeutic agents to the cancerous cells. Henceforth the development of these smart nanodevices will undoubtedly pave the way for coming up with future novel therapeutic strategies for combating the malignant cells circumventing any adverse side effects on the normal cells.

Advances in Natural Sciences: Nanoscience and Nanotechnology, 2020

Using a U-shaped glass tube where one arm contains bi-distilled water and the other arm ethyl alc... more Using a U-shaped glass tube where one arm contains bi-distilled water and the other arm ethyl alcohol (91%) separated by a platinum foil, the generated voltage across two platinum electrodes and a DC power of the order of nanoW were measured. The generated voltage lasted for many hours. The magnitude of both the voltage and power generated increased with vigorous shaking of the alcohol. Considering the absence of any significant quantity of ionic solutes in this system, voltage generation from two different polar liquids separated by a metal separator is an interesting phenomenon in the context of classical electrochemistry and seems to imply some kind of non-ionic conduction. A qualitative explanation of this phenomenon has been offered here based on the principle of Quantum Electrodynamics.

Materials Today Communications, 2021

Abstract Configuring ionic liquids (ILs) to generate synergy or to deliver multiple pharmaceutica... more Abstract Configuring ionic liquids (ILs) to generate synergy or to deliver multiple pharmaceutically active ingredients through a single compound is an emerging area in future medicine where phosphonium ionic liquids (PILs) exhibit potential as antibacterial drugs. Herein, we report the strategic development of two purely ionic mono and bis-PILs based on trihexyltetradecyl phosphonium ([TTP]+) contributing as the cation coupled with monoprotonated fluorescein ([HFl]-) and dianionic fluorescein ([Fl2-]) anions through metathesis reaction. In spite of negligible bactericidal effect of [Fl]2-, the [HFl]- and [Fl2- salts exhibit enhanced and selective bactericidal activity at drastically reduced concentrations. [TTP][HFl] exhibits bactericidal effect at 2 times lower concentration against E. coli and [TTP]2[Fl] at 10 times lower concentrations against S. aureus with respect to the precursor [TTP][Cl]. Docking studies of [TTP][HFl] and [TTP]2[Fl] as well as the precursors with two modelled bacterial cell wall fragments and three RNAs indicate direct correlation between best binding pose and experimentally obtained minimum bactericidal concentrations (MBC). The study suggests the inhibition of peptidoglycan maturation through linkage between phenolate of Fl unit and the D -Ala- D -Ala group of the peptide chain in the cell wall fragment as well as inhibition of RNA/DNA synthesis as probable mechanisms of bacterial cell death. This multistaged cell death mechanism explains the appearance of unexpectedly improved antibacterial activity and selectivity in the mono and bis- phosphonium fluorescein salts. Thus, the results recommend strong potential of the studied PILs to be used as new series of broad spectrum antibacterial agents with reduced risk for development of drug resistant strains.

Colloids and Surfaces B: Biointerfaces, 2021

Biofilm formation on medical implants and devices has been a severe concern that results in their... more Biofilm formation on medical implants and devices has been a severe concern that results in their impaired performance and life-threatening complications. Thus, development of novel functional coatings for infection prone surfaces with biofilm inhibiting characteristics is of prime significance considering the rapid emergence of multidrug resistant bacteria. Herein we present a novel nanocomposite derived from Graphene Oxide (GO) and a newly developed functional Ionic liquid (IL) obtained through a metathesis reaction between a triarylmethane dye hexamethyl pararosaniline chloride or crystal violet (CV) and sodium dodeceyl sulfate (SDS) to yield [CV][DS] (hexamethyl pararosaniline dodecyl sulfate). This highly biocompatible [CV][DS]-GO nanocomposite exhibit more than four times improved antibacterial activity in comparison to bare GO against both gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus). As suggested by XRD, FTIR and UV absorption and SEM results improved activity of [CV][DS]-GO nanocomposite is ascribed to the synergistic effect of reduced nanocomposite sheet thickness, enhanced amphiphilicity imparted by dodecylsulfate (DS), exposed active ArN+ groups of CV and some inherent functionalities of GO. This is also complemented by the ruptured and diffused S. aureus cell walls as observed in bacterial SEM result. In contrast, the nanocomposites of the precursors with GO do not demonstrate any significant antibacterial effect. Coatings developed using GO upon infestation with E. coli revealed significant biofilm formation after 48 and 72 h of incubation while [CV][DS]-GO coated surface demonstrated no colony growth under similar circumstances. Thus, [CV][DS]-GO nanocomposite coatings exhibit excellent resistance to bacterial growth even up to 72 h incubation signifying its bactericidal effect. Therefore, the developed nanocomposite may be considered as one of the improved antibacterial wash resistant coating material for biomedical devices and surfaces susceptible to to biofilm formation.

MOJ Ecology & Environmental Sciences, 2018

Using liposomal membrane of 1, 2-dipalmitoyl-sn -glycero-3- phosphatidyl choline, a well accepted... more Using liposomal membrane of 1, 2-dipalmitoyl-sn -glycero-3- phosphatidyl choline, a well accepted model for biological membrane, we have measured the change in membrane anisotropy due to incorporation of three homoeopathic drugs silicea, sulphur and calc carb and the associated values of change in Van’t Hoff enthalpy have been calculated. Our experimental results reveal that these three homoeopathic drugs affect the membrane anisotropy in different ways and this change depends upon the potency of the medicine.

Journal of Drug Delivery Science and Technology, 2020

This study reports the observed synergy in antimicrobial and anticancer activity of thymoquinone ... more This study reports the observed synergy in antimicrobial and anticancer activity of thymoquinone and piperine, encapsulated in porous guar gum micro-vehicle. Natural therapeutics like piperine and thymoquinone showed less effectivity in human medical trials due to their hydrophobicity leading to poor clinical efficacy. To overcome this problem, we have developed a delivery strategy by using guar gum, a natural biodegradable biopolymer. The successful encapsulation of phytochemicals and the microstructures of gum micro-vehicles were confirmed by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and UV-Vis spectra analysis. We also report here a significant decrease in minimum inhibitory concentration (MIC) value and synergistic bactericidal activity against four different bacterial strains and observed remarkably low median lethal dose (LD50) value against human hepatocellular carcinoma cell lines along with pH-responsive delivery of therapeutic in the case of combinatorial therapy. In our overall study, we analyze and discuss the structure, efficacy, and delivery of our designed natural therapeutic amalgamation to pave the way for augmenting the use of phytochemicals in medical applications.

Proceedings of MOL2NET 2020, International Conference on Multidisciplinary Sciences, 6th edition, 2020

The emergence of natural polymers like gums and mucilages in drug delivery systems has curbed the... more The emergence of natural polymers like gums and mucilages in drug delivery systems has curbed the rampant use of the synthetic materials for therapeutic purposes. Natural excipients offered advantages such as non-toxicity, less cost and abundantly availablity. Aqueous solubility of natural excipients plays an important role in their selection for designing immediate, controlled or sustained release formulations. This review article provides an overview of natural gum, polymers and

Materials Today Communications, 2020

A mechanistic insight into the bioaccesible herbometallic nanodrug as potential dual therapeutic ... more A mechanistic insight into the bioaccesible herbometallic nanodrug as potential dual therapeutic agent Debbethi Bera (Conceptualization) (Resources) (Methodology) (Investigation) (Writing-original draft), Kunal Pal (Investigation)

Ecotoxicology and Environmental Safety, 2020

The ability of P. laurentii strain RY1 to remediate lead (Pb 2+) from water was investigated in b... more The ability of P. laurentii strain RY1 to remediate lead (Pb 2+) from water was investigated in batch and column studies. The lead removal ability of non-viable biomass, non-viable biomass immobilised on agar-agar (biobeads) and agar-agar at different pH was compared in batch studies. It was found that among the three, biobeads have maximum ability to remove Pb 2+ followed by biomass and agar-agar beads. Maximum and almost equal lead removal by biobeads was observed at both neutral and alkaline pH making it a novel and more applicable bioremediator as all other reported bioremediators have a single pH for optimum activity. Studies were performed to determine the optimum conditions for lead removal from aqueous solutions for biobeads. The physical and chemical characterization of the biobeads before and after Pb 2+ biosorption was done by using S.E.M. and F.T.I.R. respectively. The adsorption of Pb 2+ on biobeads obeyed the Langmuir adsorption isotherm and pseudo first order kinetics. These mean that the Pb 2+ binding sites are identical, located on the surface of the adsorbant and the rate of Pb 2+ removal from aqueous solution is directly proportional to the number of Pb 2+ binding sites on the biobeads. The thermodynamics of the biosorption process is also investigated. The binding capacity of the biobeads in batch study was found to be 52.91mg/gm which is higher in comparison to other reported yeast bioremediators. The used biobeads can be desorbed using 0.1(M) CaCl 2. The desorbed biobeads can be used subsequently for several cycles of lead removal making it cost-effective. Column studies were also performed for biobeads with the help of Thomas model for examining its suitability for industrial application. Maximum specific lead uptake of the biobeads when applied in the column was found to be 58.26mg/gm which being promising makes it suitable for application in industries involved in the treatment of wastewater contaminated with high amounts of lead. The high mass transfer coefficient indicate that small sized column can be used effectively to remove high amounts of lead which makes the bioremediation process by the biobeads more economical and advantageous for industrial application. Several factors like effectiveness of the biobeads in Pb 2+ removal at both neutral and alkaline pH, reusability, high mass transfer coefficient , regenerability and high binding capacity makes it a novel versatile, cost-effective and high utility bioremediator. natural sources (bedrock, soil) and industrial emission (Cheng and Hu, 2010). Industries producing lead as waste include pulp and paper industry, tannery, fertilizer and herbicide industries, battery manufacturing industries as well as mining and metallurgical industries (Asuquo et al., 2017).

Colloids and Surfaces B: Biointerfaces, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

RSC Advances, 2018

A single LMW gelator based core–shell hydrogel with dual release kinetics.

Journal of Materials Science: Materials in Electronics, 2018

Under certain conditions, ultra high diluted triturated material achieve nanodimension. This nano... more Under certain conditions, ultra high diluted triturated material achieve nanodimension. This nanoparticle aspect of the materials has been used in various technical applications. The electrical properties of the polymer, Poly (vinylidene fluoride), commonly used as dielectric separator in high charge storage multilayer capacitor, get improved when doped with these triturated material. We have reported here how these effects get further increased by changing the doping concentration. With incorporation of 2 ml of triturated copper acetate salt, there are ~ 14.0, ~ 2.74, ~ 9.0 fold increment in β-phase, dielectric constant and ac conductivity respectively compared to the undoped polymer matrix. This is also associated with significant decrease (~ 66%) in tangent loss. Doping of these nanomaterials in the highly insulating matrix of the polymer is an effective way to fabricate composites with tunable dielectric behavior, making them a promising candidate in electronic industry. A device, using our material as separator have been designed and observed that the charge storing ability of the composite persists for more than 24 h. After 1 h of charging, maximum recorded voltage using our fabricated system is 2.034 V, whereas electrode separator system of commercial Li-polymer ion mobile battery can store 0.566 V.

Homeopathy, 2019

Background For the study of homeopathic medicines in proper perspective, emerging techniques in m... more Background For the study of homeopathic medicines in proper perspective, emerging techniques in material science are being used. Vibrational spectroscopy is one such tool for providing information on different states of hydrogen bonding as an effect of potentization. The associated change in electrical properties is also correlated with this effect. Objective From the vibrational spectra, the changes in hydrogen bonding due to dilution followed by unidirectional vigorous shaking (together termed potentization) of 91% ethanol and two homeopathic medicines Chininum purum and Acidum benzoicum have been studied. The aim was to correlate the result with the change in the electrical properties of the system. Methods Raman spectroscopy was used to study the vibrational spectra. A U-shaped glass tube (electrochemical cell), where one arm contained bi-distilled water and the other arm alcohol/homeopathic medicine (the arms being separated by a platinum foil), was used to measure the voltage ...

Homeopathy : the journal of the Faculty of Homeopathy, May 1, 2018

We report the effects of nanoparticles in homeopathic preparations of copper salts on the electr... more We report the effects of nanoparticles in homeopathic preparations of copper salts on the electrical properties of polymer film. Previous work showed that the incorporation of metal-derived homeopathic medicines increases the dielectric constant and alternating current (AC) conductivity of an electroactive polymer film that is commonly used as a capacitor in the electronic industry.We report here the effect of dilution of one homeopathic medicine, (), at 200C potency on the electrical properties of the polymer film of poly(vinylidene fluoride-co-hexafluoropropylene). 200c was incorporated in the film by the solution casting method. The electrical characteristics were measured at different frequencies using an inductance, capacitance, and resistance meter. Fourier transform infrared spectroscopy (FTIR) was performed to detect phase change in the polymer film due to the incorporation of . Morphology and particle size were studied using field emission scanning electron microscopy (F...

Advances in Natural Sciences: Nanoscience and Nanotechnology, IOP, 2020

The persistent dissemination of resistant bacterial strains is a grave contemporary global impedi... more The persistent dissemination of resistant bacterial strains is a grave contemporary global impediment in hospital-acquired infections which needs to be mitigated with immediate effect. In particular, infections from pathogenic multidrug-resistant (MDR) Gram-positive bacteria (like Enterococcus faecalis) which are resistant to conventional antibiotic therapy are attracting immediate global attention. Here we report the synthesis of nanoscale hydroxyapatites (HAPs), which are the well known biomimetic ceramic material having needle shaped morphologies. We have encapsulated vancomycin (VAN) within these nanoparticles and have conjugated the targeting ligand (folic acid) by a facile synthesis process in order to enhance the therapeutic efficacy against MDR E. faecalis. These functionalised HAPs are thoroughly characterised by employing field emission scanning electron microscopy (FESEM), powder x-ray diffraction (PXRD), ultraviolet-visible spectroscopy (UV-Vis) and dynamic light-scattering (DLS) techniques. Our results suggest that these functionalised HAPs could successfully transport vancomycin across the cell wall of MDR E. faecalis through endocytosis. The determination of selective antibacterial activity has been envisaged with the help of extensive in-vitro assays like the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and the generation of reactive oxygen species (ROS). This study vividly establishes that this folic acid conjugated HAPs are promising antibacterial agents against MDR E. faecalis and related pathogenic resistant bacterial strains.