Synthesis of flaxseed gum/melanin-based scaffold: A novel approach for nano-encapsulation of doxorubicin with enhanced anticancer activity.

Doxorubicin is a powerful chemotherapy medicine that is frequently used to treat cancer, but because of its extremely destructive side effects on other healthy cells, its applications have been severely constrained. With the aim of using lower therapeutic doses of doxorubicin while maintaining the same anti-cancerous activity as those of higher doses, the present study designs nano-encapsulation of doxorubicin by acrylamide grafted melanin as core and acrylic acid grafted flax seed gum as shell (DOX@AAM-g-ML/AA-g-FSG-NPs) for studies in-vivo and in-vitro anticancer activity. For biological studies, the cytotoxicity of DOX@AAM-g-ML/AA-g-FSG-NPs was examined on a cancerous human cell line (HCT-15) and it was observed that DOX@AAM-g-ML/AA-g-FSG-NPs exhibited very high toxicity towards HCT-15. In-vivo investigation in colon cancer-inflicted rat model also showed that DOX@AAM-g-ML/AA-g-FSG-NPs showed better anticancer activity against cancerous cells as compared to free doxorubicin. The drug release behavior of DOX@GML-GFS-NPs was studied at several pH and maximum drug release (95 %) was recorded at pH -7.2, and kinetic data of drug release was follows the Higuchi (R2 = 0.9706) kinetic model. Our study is focussed on reducing the side effects of doxorubicin by its nano-encapsulation in acrylamide grafted melanin as core and acrylic acid grafted flax seed gum that will also enhance its efficiency.

Synthesis of vildagliptin loaded acrylamide-g-psyllium/alginate-based core-shell nanoparticles for diabetes treatment.

Diabetes mellitus has become a major public health concern all over the world. Vildagliptin is one of the antidiabeticdrug that can overcome the existing problem of this prevalent disease. Present study aims to synthesize and investigate the role of vildagliptin-loaded core-shell nanoparticle of grafted psyllium and alginate (VG@P/A-NPs) in anti-diabetes application. FTIR, SEM, XRD, 13CNMR and zeta analyzer were used for characterization of the core-shell nanoparticles (VG@P/A-NPs). The synthesized acrylamide-grafted-psyllium was also optimized through varying grafting parameters such as acrylamide and ceric ammonium nitrate (CAN) concentration, time and temperature to obtain the maximum yield of acrylamide-grafted-psyllium. Rheological analysis of pure psyllium, grafted psyllium and alginate were also performed. For biological studies, the first cytotoxicity of grafted psyllium and VG@P/A-NPs were examined on human lung adenocarcinoma cell line A549 in which it was observed that VG@P/A-NPs did not exhibited any toxicity. The antidiabetic potential of VG@P/A-NPs was investigated by glucose uptake assay, using TNF-α induced insulin resistance skeletal cell model using mouse muscle L6 cell line. The insulin signaling impaired cell line displayed a highly significant (p < 0.0001) dose-dependent increase in glucose uptake after treatment with increasing doses of VG@P/A-NPs.The drug release behavior of VG@P/A-NPs was examined at various pH and the highest drug release (98 %) was obtained at pH (7.4). The drug release kinetic data was following the Higuchi (R2 = 0.9848) kinetic model, suggesting the release of drug from vildagliptin-loaded grafted psyllium-alginate core-shell nanoparticles (VG@P/A-NPs) as a square root of time-dependent process and diffusion controlled. This study provides an economical and environment-friendly approach towards the synthesis of VG@P/A-NPs with antidiabetes applications.

Synthesis of rifaximin loaded chitosan-alginate core-shell nanoparticles (Rif@CS/Alg-NPs) for antibacterial applications.

The present work aims to synthesize the rifaximin loaded chitosan-alginate core-shell nanoparticles (Rif@CS/Alg-NPs) for antibacterial applications. The core-shell nanoparticles (Rif@CS/Alg-NPs) were characterized by Fourier Transform Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-rays diffraction (XRD) and zeta analyzer. The antibacterial activities of Rif@CS/Alg-NPs were investigated against three species of bacteria namely Escherichia coli (E. coli), Pseudomonas aeruginosa (PA) and Bacillus haynesii (BH). Rif@CS/Alg-NPs exhibited outstanding antibacterial activities against E. coli, P. aeroginosa and Bacillus haynesii (BH) with 24 mm, 30 mm and 34 mm zone of inhibitions, respectively. Cytotoxicity of Rif@CS/Alg-NPs was also evaluated against human lung adenocarcinoma cell line A549 and found to be nontoxic. The drug release behavior of Rif@CS/Alg-NPs was investigated at different pH levels and maximum drug release (80%) was achieved at pH (7.2). The drug release kinetic data followed the Higuchi (R2 = 0.9963) kinetic model, indicating the drug release from Rif@CS/Alg-NPs as a square root of time-dependent process and diffusion controlled. Current research provides a cost-effective and green approach toward the synthesis of Rif@CS/Alg-NPs for its antibacterial applications.

Synthesize and characterization of binary grafted psyllium for removing toxic mercury (II) ions from aqueous solution.

Acrylamide and acrylonitrile were grafted on psyllium employing ceric ammonium nitrate (CAN) as initiator under N2 atmosphere to get an adsorbent of mercury ions. The synthesized adsorbent was optimized by varying synthetic parameters viz. monomer concentration, reaction time, temperature, initiator concentration, etc. to obtain the maximum yield of the grafted product as well as maximum adsorption of ionic mercury. The synthesized adsorbent was characterized by FT-IR, SEM, XRD, zeta potential and thermal techniques. The effect of various process parameters such as pH, time, adsorption dose and temperature on Hg (II) adsorption was investigated. The maximum Hg (II) adsorption (96%) was achieved at temperature (30 °C), dose (30 mg), pH (6), time (60 min) and initial concentration of mercury with 100 ppm. The Hg(II) adsorption on Psy-g-Poly (Am-co-An) was confirmed by XPS study. The isotherm data of the adsorption experiments obeyed the classical Langmuir adsorption isotherm. On the other hand, the kinetic data followed the second-order kinetics, indicating the chemisorption mechanism.

Modified bacterial cellulose based self-healable polyeloctrolyte film for wound dressing application.

In this investigation, we prepare a self-healable polyelectrolyte film via crosslinking the cationically charged chitosan (Cts) with anionically modified bacterial cellulose (BC), which is a green source of nano-filler. This polyelectrolyte film is able to show dynamic self-healing activity at physiological pH condition via adapting ionic interaction, a state of non-covalent bond. BC was prepared using Glucanoacetobacter xylinus (MTCC7795) bacteria and after that its surface was modified with anionic poly(acrylic acid) using "grafting from" technique. It was observed that the notch (single and multiple) created over the composite film was disappeared by showing vibrant diffusion and ionic interlocking in contact with buffer solution having physiological pH. The XTT assay revealed that the composite film is non-toxic in nature and it was witnessed that the composite film was capable of delivering curcumin, a hydrophobic drug that has an ability to show antimicrobial activity and wound healing capability.

Effect of electric impulse for improved energy generation in mediatorless dual chamber microbial fuel cell through electroevolution of Escherichia coli.

The main emphasis of this study is to understand the electroactive behavior of a microbe in microbial fuel cell (MFC) under specific selection pressure. This study explores potential of a non-electrogenic microbe for power production in a mediatorless MFC under the influence of a specific stress. Electric pulse of specific magnitude has been applied to Escherichia coli cells in a MFC and compared the results with unpulsed (control) MFC. Maximum power density of 187.77 mW/m(2) and 284.44 mW/m(2) for the control and experimental MFC has been observed at corresponding current density of 1444.44 mA/m(2) and 1777.77 mA/m(2). The results show improved performance for the pulsed (experimental) system, despite of initial downfall with respect to the control system. This suggests bacterial adaptation against electrical pulses which leads to evolution of an efficient electrogen. This observation is further confirmed by analyzing the results of Cyclic Voltammetry (CV), Scanning Electron Microscopy (SEM) Electrochemical Impedence Spectroscopy (EIS), enlightening different attributes like electrochemical property, bacterial morphology and impedance. The study is focused on development of a microbial fuel cell catalysed by E. coli, through triggering electroactive property in the microbe by exposing it to external stress. This study is unique in nature as it is mediatorless, economical and describes about a new method of natural bacterial evolution.

Aromatic π-Conjugated Curcumin on Surface Modified Polyaniline/Polyhydroxyalkanoate Based 3D Porous Scaffolds for Tissue Engineering Applications.

Curcumin-entrapped polyaniline (PAni)-conjugated poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) electroconductive porous scaffolds were fabricated for application in tissue engineering. The physical and chemical characterizations of the as-prepared biomaterials were performed by UV-vis and ATR/FT-IR spectrophotometric, thermogravimetric, fluorescence microscopic, and X-ray diffractometric analyses. It was observed that compared to the pure PHBV copolymer, which is an insulator, the electroconductivity of the PAni-modified PHBV copolymer increased up to the value of 5.78 × 10-5 S cm-1. An antimicrobial study revealed that the curcumin-loaded biomaterials exhibited better bactericidal effect against Gram-positive bacterial strains compared to Gram-negative strains. The composite also demonstrated significant compatibility toward blood and fibroblast cells and exhibited the maximum cell viability (90% to 80%). Cell migration and proliferation on the injured tissues were found to occur at a faster rate, resulting in faster repair, in the presence of anti-inflammatory and anticancer curcumin drug loaded composites compared to that of the pure PHBV copolymer.

Performance evaluation of microbial fuel cells: effect of varying electrode configuration and presence of a membrane electrode assembly.

Membrane electrode assembly (MEA), a common arrangement used in direct methanol fuel cells, has been employed in a fed-batch mode microbial fuel cell (MFC), using mixed microbial population. This modification has been done for analyzing the prospect of obtaining increased power productivity. In addition, the electrodes have also been configured for the purpose of better current collection. Use of MEA as a replacement of the conventionally used 'separate membrane and electrode' arrangement has evidently resulted in reducing one of the limiting factors for higher power production in MFC, that is, its internal resistance. Open circuit potentials of more than 1 volt have been obtained for two MFC setups: (a) one consisting of an MEA and (b) the other having electrodes situated 2 cm apart from each other, but having better current collectors than the first setup. Power densities of 2212.57 mW m(-2) and 1098.29 mW m(-2) have been obtained at corresponding current densities of 5028.57 mA m(-2) and 3542.86 mA m(-2), respectively. The potential and power obtained for the MFC consisting of an MEA is quite significant compared to the other systems employed in this study.

Utilization of proteinaceous materials for power generation in a mediatorless microbial fuel cell by a new electrogenic bacteria Lysinibacillus sphaericus VA5.

In this study, a bacterial strain, Lysinibacillus sphaericus which is relatively new in the vast list of biocatalysts known to produce electricity has been tested for its potential in power production. It is cited from the literature that the organism is deficient in some sugar or polysaccharide processing enzymes and thus is tested for its ability to utilize substrates mainly rich in protein components like beef extract and with successive production of electricity. The particular species has been found to generate a maximum power density of 85mW/m(2) and current density of ≈270mA/m(2) using graphite felt as electrode. The maximum Open Circuit Voltage and current has been noted as 0.7Vand 0.8mA during these operational cycles. Cyclic voltammetry studies indicate the presence of some electroactive compounds which can facilitate electron transfer from bacteria to electrode. The number of electrogens able to generate electricity in mediator free conditions are few, and the study introduces more divergence to that population. Substrate specificity and electricity generation efficacy of the strain in treating wastewater, specially rich in protein content has been reported in the study. As the species has been found to be efficient in utilizing proteinaceous material, the technique can be useful to treat specific type of wastewaters like wastewater from slaughterhouses or from meat packaging industry. Treating them in a more economical way which generates electricity as a outcome must be preferred over the conventional aerobic treatments. Emphasizing on substrate specificity, the study introduces this novel Lysinibacillus strain as a potent biocatalyst and its sustainable role in MFC application for bioenergy generation.

Blood compatible N-maleyl chitosan-graft-PAMAM copolymer for enhanced gene transfection.

To improve transfection efficiency, we prepared N-maleyl chitosan-graft-polyamidoamine (NMCTS-graft-PAMAM) copolymer. Self-assembled NMCTS-graft-PAMAM/pDNA complexes were prepared by complex coacervation method at different N/P (nitrogen to phosphate ratio) ratios. The copolymer effectively formed complexes with pDNA at lower N/P ratio (N/P ratio 1.0) than that of unmodified chitosan (N/P ratio 2.0) and the complexes were spherical with particle size of 100-150 nm. The copolymer showed significant protection of DNA from nuclease attack with lower toxicity against HeLa cell. The copolymer also showed no noticeable hemolytic effects up to 10mg/mL indicating no detectable disturbance of the red blood cell membranes. The transfection efficiency of the copolymer was increased significantly compared to that of chitosan and reached up to 36±2% at N/P ratio 7.0 which was higher than that of PEI (30±3% at N/P ratio 10). Therefore, the copolymer may be a strong alternative candidate as effective nonviral vector.

Reversible assembly and disassembly of amphiphilic assemblies by electropolymerized polyaniline films: effects rendered by varying the electropolymerization potential.

Polymer films that respond to a variety of stimuli are attractive candidates for location-specific guest molecule delivery. These systems release the guest molecules by polymer erosion; thus, these are mono-use systems. If a polymer film is used to disassemble amphiphilic assemblies containing sequestered guest molecules, the polymer erosion issue can be circumvented. However, charge-bearing vinyl polymers, upon interaction with amphiphilic assemblies, are known to adapt to a conformation that results in encapsulating guest molecules instead of releasing them. On the contrary, it has earlier been reported that a rigid, charge-bearing, and water-insoluble conjugated polyaniline film can effectively disassemble amphiphilic assemblies without causing much harm to the film. Herein, we demonstrate the effect rendered by varying the electropolymerization potential on the interaction efficiency between the positive charge-bearing polyaniline film and oppositely charged amphiphilic assemblies. In addition, it is also demonstrated that a film of oxidized polyaniline can be regenerated for repetitive disassembly of the amphiphilic assemblies, and concomitant guest molecule delivery.

Novel conjugated linseed oil-styrene-divinylbenzene copolymers prepared by thermal polymerization. 1. Effect of monomer concentration on the structure and properties.

A variety of novel opaque, white polymers ranging from rubbery materials to tough and rigid plastics have been prepared by the thermal polymerization at 85-160 degrees C of varying amounts of 87% conjugated linseed oil, styrene, and divinylbenzene. Gelation of the reactants typically occurs at temperatures higher than 120 degrees C, and fully cured thermosets are obtained after postcuring at 160 degrees C. The fully cured thermosets have been determined by Soxhlet extraction to contain approximately 35-85% cross-linked materials. The microcomposition of these polymers, as determined by 1H NMR spectroscopy, indicates that the cross-linked materials are composed of both soft oily and hard aromatic phases. After solvent extraction, the insoluble materials exhibit nanopores well distributed throughout the polymer matrixes. Dynamic mechanical analysis of these polymers indicates that they are phase separated with a soft rubbery phase having a sharp glass transition temperature of -50 degrees C and a hard brittle plastic phase with a broadened glass transition temperature of 70-120 degrees C. These polymers possess cross-link densities of 0.15-2.41 x 10(4) mol/m3, compressive Young's moduli of 12-438 MPa, and compressive strengths of 2-27 MPa. These materials are thermally stable below 350 degrees C and exhibit a major thermal degradation of 72-90% at 493-500 degrees C.