Genipin crosslinked curcumin loaded chitosan/montmorillonite K-10 (MMT) nanoparticles for controlled drug delivery applications.

Here, we have reported the influence of MMT and genipin in releasing curcumin from the Genipin crosslinked Chitosan/MMT nanoparticles, prepared by ionic gelation method. The nanoparticles were characterised using Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). Zeta potential and average diameter of the nanoparticles were found in the range 32-47 mV and 430-560 nm. Swelling and release of curcumin from the nanoparticles increased with the decrease in pH of the medium, MMT, and genipin content. Curcumin released from the nanoparticles reduced the viability of MCF-7 and Hep G2 cells as compared to untreated cells. The nanoparticles increased the level of reduced glutathione (GSH), superoxide dismutase (SOD), and catalase level in human PBMCs and decreased the level of Lipid peroxidation suggesting an enhanced protection against cellular damage. Lower pH and higher MMT concentration in the nanoparticles improved the mucoadhesive properties.

A comparative study on the properties of graphene oxide and activated carbon based sustainable wood starch composites.

Activated carbon (AC) prepared from Jatropha curcas and graphene oxide (GO) were employed in the preparation of natural polymer based wood starch composites (WSC) through the solution blending technique using water as a solvent. In this study, methyl methacrylate (MMA) was grafted onto the starch polymer and this MMA grafted starch (MMA-g-starch) was cross-linked with the cheap soft wood flour using the citric acid as cross-linker and water as a solvent in the whole process. The prepared GO and AC were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), thermogravimetric analysis (TGA) and Raman study. The interaction of GO and AC, with MMA-g-starch, citric acid and wood were studied by FTIR, XRD and SEM analysis. The GO and AC treated composites exhibited outstanding mechanical properties, thermal stability and fire resistance properties. The tensile strength of the composites increased by 178% and 200% with addition of 2 phr AC and GO respectively compared to untreated composites. A significant enhancement in water resistance properties of GO and AC treated composites was also attained. The study showed that the properties of the composites containing AC prepared from the seeds of Jatropha curcas was quite comparable with the composites reinforced with GO.

Bioremediation of arsenic from water with citric acid cross-linked water hyacinth (E. crassipes) root powder.

A green and novel approach was demonstrated for successful remediation of arsenic from contaminated water by citric acid (CA) cross-linked water hyacinth root powder (RP). Different analytical techniques were used to investigate the binding and structural properties of prepared materials. Titanium dioxide played a significant role in the cross-linking process. Incorporation of CA into RP enhanced its integrity, and thus removal efficiency remained unaffected after several cyclic runs. Also the turbidity which formed due to treatment with uncross-linked RP was reduced to below the permissible limit. Effect of the amount of CA, material dose, treatment time, initial ion concentration, and pH were investigated. Use of 10% (w/w) CA was found to be sufficient to bring down the turbidity of the treated water below 2.5 nephelometric turbidity unit (NTU) without hampering the removal capacity/rate. A material dose of 5 g/L removed successfully total inorganic arsenic concentration to below 10 µg/L. The sorption process could be reasonably explained by Langmuir isotherm, and the maximum adsorption capacity was found to be 28 µg of arsenic/g. The material was found to be more efficient at acidic pH (pHZPC = 6.72). The sorption process was governed by a pseudo-second-order kinetic model.

Equilibrium and kinetics study on removal of arsenate ions from aqueous solution by CTAB/TiO2 and starch/CTAB/TiO2 nanoparticles: a comparative study.

We present a comparative study on the efficacy of TiO2 nanoparticles for arsenate ion removal after modification with CTAB (N-cetyl-N,N,N-trimethyl ammonium bromide) followed by coating with starch biopolymer. The prepared nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), thermogravimetry, scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDX). The removal efficiency was studied as a function of contact time, material dose and initial As(V) concentration. CTAB-modified TiO2 showed the highest arsenate ion removal rate (∼99% from 400 µg/L). Starch-coated CTAB-modified TiO2 was found to be best for regeneration. For a targeted solution of 400 µg/L, a material dose of 2 g/L was found to be sufficient to reduce the As(V) concentration below 10 µg/L. Equilibrium was established within 90 minutes of treatment. The sorption pattern followed a Langmuir monolayer pattern, and the maximum sorption capacity was found to be 1.024 mg/g and 1.423 mg/g after starch coating and after CTAB modification, respectively. The sorption mechanisms were governed by pseudo second order kinetics.

Encapsulation of active ingredients in polysaccharide-protein complex coacervates.

Polysaccharide-protein complex coacervates are amongst the leading pair of biopolymer systems that has been used over the past decades for encapsulation of numerous active ingredients. Complex coacervation of polysaccharides and proteins has received increasing research interest for the practical application in encapsulation industry since the pioneering work of complex coacervation by Bungenburg de Jong and co-workers on the system of gelatin-acacia, a protein-polysaccharide system. Because of the versatility and numerous potential applications of these systems essentially in the fields of food, pharmaceutical, cosmetics and agriculture, there has been intense interest in recent years for both fundamental and applied studies. Precisely, the designing of the micronscale and nanoscale capsules for encapsulation and control over their properties for practical applications garners renewed interest. This review discusses on the overview of polysaccharide-protein complex coacervates and their use for the encapsulation of diverse active ingredients, designing and controlling of the capsules for delivery systems and developments in the area.

Evaluation of folic acid tagged aminated starch/ZnO coated iron oxide nanoparticles as targeted curcumin delivery system.

The role of 'superparamagnetic iron oxide nanoparticles' has gained considerable interest in various biomedical applications. However extensive researches are still going on to modify the nanoparticle size, surface properties etc. in order to get full benefit of the material. In this study, iron oxide nanoparticles have been modified with folic acid tagged aminated starch/ZnO coating to formulate a targeted drug delivery system. The nanoparticles were characterized by Fourier Transform Infra-red Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy. Both the swelling and in vitro drug release was performed in both acidic and alkaline pH. The cytotoxicity of the drug loaded nanoparticles was analysed by MTT assay in human lymphocytes, HepG2 and MCF7 cell lines. The cell uptake efficiencies and Reactive Oxygen Species generation with the drug loaded nanoparticles was estimated in HepG2 cell lines. The uptake capacity of fluorescein isothiocyanate tagged nanoparticles was assessed by fluorescence microscope.

Effect of crosslinker on drug delivery properties of curcumin loaded starch coated iron oxide nanoparticles.

Aminated starch coated iron oxide magnetic nanoparticles loaded with curcumin were synthesized via coprecipitation technique. The nanoparticles were crosslinked by using three different crosslinkers: glutaraldehyde, genipin and citric acid and the effect of crosslinking on different properties of the nanoparticles was evaluated. Characterisation of the nanoparticles was done with FTIR (Fourier Transform Infrared spectroscopy) and XRD (X-Ray Diffraction). Magnetic property study using VSM (Vibrating Sample Magnetometer) showed their superparamagnetic nature. Morphology of the nanoparticles was studied by SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy). Zeta potential values showed that crosslinking imparted stability to the system. Crosslinking also enhanced drug loading and encapsulation efficiency of the system. Swelling and in vitro studies of the nanoparticles showed that the release of drug was dependent on time, crosslinker nature, crosslinker concentration and pH of the medium. The aminated starch coated nanoparticles also showed good mucoadhesive character. The cell viability assessment by MTT study revealed their compatibility with human lymphocytes cells and their considerable cell growth inhibiting properties with MCF7 and HepG2 cells. The nanoparticles showed good internalization in HepG2 cells along with considerable ROS formation.

Functionalization of MWCNT and their application in properties development of green wood nanocomposite.

Starch based wood nanocomposites (WSNC) were prepared successfully from starch and soft wood with multi-walled carbon nanotube (MWCNT) as nano reinforcing agent through a completely green path. The most important part of this scheme was the use of water as the solvent. In this technique, starch was grafted with methylmethacrylate (MMA) and MWCNT was functionalised with hydroxyl groups (f-MWCNT). Dimethyloldihydroxyethyleneurea (DMDHEU) was used as a cross-linker to prepare the green material from methylmethacrylate grafted starch (MMA-g-starch), soft wood flour and functionalised MWCNT. The functionalization of MWCNT was confirmed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Raman analysis. Different properties of the WSNC were investigated by varying the concentration of f-MWCNT. The prepared nanocomposites exhibited outstanding thermal stability, mechanical properties and water resistance capacity compared to untreated wood composites. The flammability of the wood composites decreased up to 30% with just addition of 0.50phr f-MWCNT.

Carboxymethyl starch-chitosan-coated iron oxide magnetic nanoparticles for controlled delivery of isoniazid.

CONTEXT: The coating material of magnetic nanoparticles plays a great role in drug delivery application. The coatings not only increase the stability of the nanoparticles but also improve the drug release pattern, biocompatibility and mucoadhesivity. OBJECTIVE: Montmorillonite (MMT) containing magnetic iron oxide nanoparticles coated with polyelectrolyte complex (PEC) of carboxymethyl starch-chitosan were prepared for controlled release applications. METHOD: The PEC-coated nanoparticles were characterised by Fourier Transmission Infra-red spectroscopy and X-ray diffraction, scanning electron microscope, transmission electron microscope, and dynamic light scattering. Cytotoxicity study was performed by MTT assay analysis. Mucoadhesivity test was performed by using in vitro wash off and ex vivo method. RESULT: The coating of PEC showed good stability, biocompatibility and mucoadhesivity of the iron oxide magnetic nanoparticles. MMT addition enhanced the swelling, drug loading and release and also the cytotoxicity and mucoadhesivity of the nanoparticles. CONCLUSION: This study revealed that the MMT incorporated PEC of CMS-CS can be effectively used for coating of iron oxide nanoparticles.

Effect of crosslinker and nanoclay on starch and jute fabric based green nanocomposites.

'Green' nanocomposites were prepared by solution induced intercalation method using starch, jute, glutaraldehyde, nanoclay and glycerol. The concentration of glycerol was optimised. The synthesized composites were characterized by various physicochemical and spectrochemical techniques such as Fourier transform infrared spectroscopy, X-ray diffractometry, transmission electron microscopy, scanning electron microscopy, and thermogravimetric analysis. Fourier transform infrared spectroscopy study indicated an interaction between the jute, starch and clay. Good adhesion exists between starch and jute surface as revealed by scanning electron microscope study. The extent of exfoliation of clay was studied by X-ray diffraction and transmission electron microscope studies. The addition of glutaraldehyde and nanoclay has been found to improve the thermal stability, flame retardancy, dimensional stability and mechanical strength of the prepared composite.

Microencapsulation of isoniazid in genipin-crosslinked gelatin-A-κ-carrageenan polyelectrolyte complex.

BACKGROUND: Microspheres of gelatin-A and κ-carrageenan were prepared by using genipin, a naturally occurring crosslinker, and sunflower oil as reaction media. METHOD: The variations in the size of the microspheres formed by varying the amount of surfactant (0.33-1.0 g/g of polymer), polymer (1.5-3.0 g), and crosslinker (0.2-0.8 mmol) were studied by scanning electron microscopy. The encapsulation of isoniazid was carried out by absorption. The isoniazid content in the prepared microspheres was determined. The release characteristic of isoniazid was also studied at pH values 1.2 and 7.4 by using UV-spectrophotometer. RESULTS: Characterization of the isoniazid-loaded microspheres was carried out by using Fourier transform infrared spectrophotometry, differential scanning calorimetry, and X-ray diffractometery.

Preparation and evaluation of gelatin/sodium carboxymethyl cellulose polyelectrolyte complex microparticles for controlled delivery of isoniazid.

The ratio of gelatin to sodium carboxymethyl cellulose (SCMC) at which maximum yield was obtained was optimized. This optimized ratio of gelatin to SCMC along with other parameters was used to prepare microparticles of different sizes. Vegetable oil was used as emulsion medium. Effect of various factors like amount of surfactant, concentration of polymer on the formation, and size of the microparticles was investigated. These microparticles were used as carrier for isoniazid. Among different cross-linkers, glutaraldehyde was found to be the most effective cross-linker at the temperature and pH at which the reaction was carried out. The loading efficiency and release behavior of loaded microparticles were found to be dependent on the amount of cross-linker used, concentration of drug, and time of immersion. Maximum drug loading efficiency was observed at higher immersion time. The release rate of isoniazid was more at higher pH compared to that of at lower pH. The sizes of the microparticles were investigated by scanning electron microscope. In all the cases, the microparticles formed were found spherical in shape except to those at low stirring speed where they were agglomerated. Fourier transform infrared study indicated the successful incorporation of isoniazid into the microparticles. Differential scanning calorimetry study showed a molecular level dispersion of isoniazid in the microparticles. X-ray diffraction study revealed the development of some crystallinity due to the encapsulation of isoniazid.