Chitosan Amine Research Articles

Characterization of the polysaccharide schizophyllan and schizophyllan-chitosan hydrogel formation by diffusing-wave spectroscopy.

Schizophyllan (SPG) is a semi-flexible, triple-helical polysaccharide with attractive properties as an efficient viscosifying compound and biological response modifier. We report microrheological characterization of schizophyllan as dispersed in solution and the changes associated when crosslinked with chitosan over an extended frequency range using diffusing wave spectroscopy (DWS). A SPG with high molecular weight (Mw=1.1×106Da) was selectively oxidized in the side chains (20% or 40%) to promote Schiff base formation with chitosan (CHI) amine groups, thus inducing crosslinking. The microrheological characterization of the dispersed SPG revealed characteristic features of the semiflexible structure, where also coupling between flexure and longitudinal modes was indicated based on scaling coefficient close to 7/8 of the loss modulus G"(ω) vs ω for ω in the range 3×103-105rad/s. The in-situ characterization of the gelation process by DWS revealed changes in the scattered intensity-correlation function caused by the embedded colloidal probe-particles, from which the mean-square displacement of the probes and the shear moduli of the SPG-chitosan hydrogel samples were determined for various SPG concentrations and degrees of oxidation. It is found that SPG - chitosan hydrogels can be prepared with a polymer content in the range of 0.5-2.0mg/mL and that tuning the molecular parameters allowed control of mechanical moduli in soft hydrogels in the range of 0.3Pa up to 1000Pa.

Antibacterial nanofibrous wound dressing mats made from blended chitosan-copper complexes and polyvinyl alcohol (PVA) using electrospinning

Chitosan is promising for wound care solutions owing to its high biocompatibility, biodegradability, hemostasis, antimicrobial activity, and promotion of tissue regeneration. However, its antibacterial property is insufficient for some infected wounds and local conditions. Given the high antibacterial activity of copper, this work focused on synthesizing chitosan-copper complexes with 1, 3, 6, 12, 24, and 48 % copper to chitosan's amine groups, followed by electrospinning them with polyvinyl alcohol. The mats exhibited promising vapor transition rates ranging from 2800 ± 33 to 3201 ± 48 g/m2.day and a dual-phase release of copper, with an initial burst followed by a sustained release over 7 days. Superior fibroblast cell cytocompatibility was observed up to 12 % copper, with accelerated re-epithelialization and cell migration to 6 % copper. Antibacterial efficacy against both gram-positive Staphylococcus aureus)S. aureus(and gram-negative Escherichia coli (E. coli) bacteria was effective beyond 3 % copper. Typically, the optimal concentration of copper was identified at 6 %, exhibiting a balance of antibacterial activity and biocompatibility, with the ability to cover 98.0 ± 0.8 % of the wound area in only 24 h and increase cell proliferation by 189 ± 11 % within 5 days.

Poly(ε-caprolactone)-grafted-chitosan copolymers: Synthesis and use as tunable and biodegradable coating for water soluble fertilizers

The urgent need for efficient agriculture to increase crop and food has fueled the development of coated fertilizers with a slow-release kinetics, water economy and full degradability to avoid negative environmental impact. In this context, we herein report the synthesis of poly(ε-caprolactone) (PCL) grafted from chitosan (CS) as a new class of biodegradable coating materials. The CS-g-PCL were prepared following a one-pot, two-step strategy, in which the primary amines of CS first react with ε-caprolactone (CL) to form CL-oligomers linked to CS via amide bonds terminated with hydroxyls, which together with the native hydroxyls of CS initiate the ring-opening polymerization of CL after addition of Sn(C ≡ CPh)4 as catalyst. Owing to the great stability of the used catalyst, the high molar mass of PCL grafted onto CS was successfully obtained under trivial open-air conditions. Different copolymers (CS-g-PCL) were prepared by varying the CS content. The structural characterization of CS-g-PCL was carried out using FTIR, 1H NMR, X-ray diffraction, contact angle and size exclusion chromatography (SEC) while the thermal and mechanical characterization of the prepared CS-g-PCL were compared to the neat PCL. Next, using a laboratory rotary drum, CS-g-PCL was implemented to uniformly coat granular diammonium phosphate fertilizer (DAP). Consequently, the kinetic releases of nitrogen and phosphorus were significantly delayed compared to that observed from uncoated DAP (conventional fertilizers). Finally, the degradation of CS-g-PCL was examined under aerobic conditions and showed a significant increase in their biodegradability with respect to neat PCL.

Highly efficient and reusable CuAu nanoparticles supported on crosslinked chitosan hydrogels as a plasmonic catalyst for nitroarene reduction

The synthesis of CuAu-based monometallic (MNPs) and bimetallic nanoparticles (BNPs) supported on chitosan-based hydrogels for their application as catalysts is presented. The hydrogels consisted of chitosan chains cross-linked with tripolyphosphate (TPP) in the form of beads with an approximate average diameter of 1.81 mm. The MNPs and BNPs were obtained by the adsorption of metallic ions and their subsequent reduction with hydrazine, achieving a metallic loading of 0.297 mmol per gram of dry sample, with average nanoparticle sizes that were found between 2.6 and 4.4 nm. Both processes, metal adsorption and the stabilization of the nanoparticles, are mainly attributed to the participation of chitosan hydroxyl, amine and amide functional groups. The materials revealed important absorption bands in the visible region of the light spectra, specifically between 520 and 590 nm, mainly attributed to LSPR given the nature of the MNPs and BNPs inside the hydrogels. Subsequently, the hydrogels were evaluated as catalysts against the reduction of 4-nitrophenol (4NP) into 4-aminophenol (4AP), followed by UV–visible spectroscopy. The kinetic advance of the reaction revealed important improvements in the catalytic activity of the materials by synergistic effect of BNPs and plasmonic enhancement under visible light irradiation, given the combination of metals and the light harvesting properties of the nanocomposites. Finally, the catalytic performance of hydrogels containing BNPs CuAu 3:1 showed an important selectivity, recyclability and reusability performance, due to the relevant interaction of the BNPs with the chitosan matrix, highlighting the potential of this nanocomposite as an effective catalyst, with a potential environmental application.

Polyelectrolyte Complexation of Chitosan and WS2 Nanotubes

AbstractThe inclusion of tungsten disulphide nanotubes (WS2 NTs) in chitosan, plasticized with glycerol, facilitates the formation of a polyelectrolyte complex. The glycerol interrupts the intramolecular hydrogen bonding between chitosan chains allowing positively charged protonated amines of chitosan to form a complex with negatively charged oxygen ions chemisorbed to the tungsten atoms in defects. These interactions, with the unique mechanical and chemical properties of WS2 NTs, result in a chitosan film with superior properties relative to unfilled chitosan. Even at low WS2 NT loadings (≤1 wt%), the Young's modulus (E) increases by 59%, tensile strength (σ) by 40% and tensile toughness by 74%, compared to neat chitosan, without sacrificing ductility. Addition of highly dispersed WS2 NTs significantly improves the gas barrier properties of chitosan, with a 50% reduction in oxygen permeability, while the addition of both glycerol and WS2 NTs to chitosan effectively reduces the carbon dioxide permeability by 80% and the water vapor transmission rate by 90%. The intrinsic antimicrobial efficacy of chitosan against both Gram‐positive and Gram‐negative bacteria is enhanced on inclusion of WS2 NTs. Polyelectrolyte complexation of WS2 NTs and glycerol‐plasticized chitosan provides a cost‐effective, sustainable route to biodegradable films with desirable mechanical, gas barrier properties, and antimicrobial efficacy suitable for food packaging applications.

Fabrication and Surface Modification of PVDF Membrane for Zinc and Cadmium ions Removal

Rapid industrialization and urbanization in this era have leads to water pollution and worsen the water scarcity. In this study, a modified poly(vinylidene fluoride) (PVDF) membrane was used to remove zinc and cadmium ions from solutions with concentrations of 10 ppm and 50 ppm, respectively. The hydrophobic PVDF support membrane was modified by a Layer-by-Layer (LbL) deposition technique with polycation, chitosan, and polyanion, poly(styrene sulfonate) to increase its hydrophilicity and metal ions rejection percentage as well as decreasing membrane fouling. Chitosan's hydroxyl and amine groups created an electrostatic interaction with the sulfonate group of poly(styrene sulfonate).The polyelectrolyte-modified membranes were characterized by using infrared spectroscopy and water contact angle measurements. The membrane filtering experiments revealed that the 5, 6, 9, and 10 layers of polyelectrolytes deposited membranes retained zinc/ and cadmium ions well, demonstrating the practicality of polyelectrolytes deposition on organic membranes because all rejection percentages were greater than 25%. The robustness of modified membranes was also tested by repeating 10 consecutive filtrations with the same membrane, and it was demonstrated that the modified membrane still had a higher rejection percentage that was two times higher and was less likely to foul due to less decreasing trends in permeate flux when compared to the unmodified membrane. It is expected that electrostatic repulsion and attraction as well as the steric effect were the primary mechanisms by which the modified membrane removed metal ions from contaminated solution.

Heterogeneous Radioinduced Graft Copolymerization of Caprolactone in Nanochitosan

This work focus on the chitosan-caprolactone graft copolymers’ (Ch-g-CL) synthesis through Radio Induced Grafting (RIG) of heterogeneous blends of solid chitosan polymers (particulated and nanoprecipitated) and liquid ε-caprolactone monomer, without the need of further reagents nor dissolution. The irradiation process was conducted at room temperature with gamma radiation from 60Co, followed in air and also under vacuum. Commonly applied sterilization doses of 25 and 45 kGy were used. The samples were analyzed, before and after irradiation, through FTIR-ATR, elemental analysis, scanning electron microscopy, 1H-NMR and size exclusion chromatography (SEC). It was found that copolymerization was successful on the blends with nanochitosan, due to a drastic increase in the active surface of the biopolymer. It was observed that the incorporation was better at higher doses and while irradiated on air, with up to 29% caprolactone incorporation. FTIR studies, along with elemental analysis and SEC, indicate that the most probable reaction is caprolactone grafting from/onto chitosan's amine groups. It was also observed that the incorporation increased in the higher molecular weight chitosan, which also has higher amine content. Practically, copolymers with 5–10% grafting sites with CL side chains of up to nine units, were obtained depending on the case. These RIG syntheses showed to lead to tunable Ch-g-CL structures of interest for biomedical applications as tissue scaffolds and drug delivery systems.

Bicarbonate-mediated dissolution of chitosan-based polyelectrolyte complex gels

Using chitosan/alginate polyelectrolyte complexes (PECs) as the primary model system, we demonstrate and systematically analyze mild and facile chitosan-based PEC gel dissolution in sodium bicarbonate (NaHCO3) solutions. The reversible conversion of chitosan amine groups to carbamate groups dissociates the ionic bonds between chitosan and its complexing polyanion while simultaneously solubilizing the dissociated chitosan, which causes the gels to dissolve. The PEC composition-dependent minimum NaHCO3 concentrations needed for this dissolution, for the materials examined herein, do not exceed a few hundred mM, and the dissolution rate increases with both the NaHCO3 concentration and the stoichiometric imbalance between the chitosan amine and alginate carboxylate groups within the PECs. The PEC dissolution rates also generally increase with the stirring speed but (depending on the PEC composition) can become insensitive to stirring when (1) the gels float and (2) at higher stirring speeds where transport of NaHCO3 to the PEC gel surface ceases to be a rate-determining step in the dissolution process. While the above effects are primarily demonstrated using chitosan/alginate PECs, extension of this NaHCO3-mediated dissolution approach to other chitosan-based PECs (i.e., those formed with synthetic polyanions) is also demonstrated. Collectively, these findings advance a non-destructive method of dissolving chitosan-based PEC gels (which could be advantageous for their compositional analysis or recycling) and provide guidelines for this method's application.

Vanillin crosslinked 3D porous chitosan hydrogel for biomedicine applications: Preparation and characterization

Crosslinked chitosan (CS) is one of the most useable hydrogels in biomedicine and tissue engineering. Unlike most chitosan crosslinkers that are toxic, such as glutaraldehyde, vanillin is a natural, biocompatible, and antimicrobial alternative. The crosslinking of chitosan and vanillin consists of Schiff base bonds between the amines of chitosan and the aldehydes of vanillin, in addition to hydrogen bonds formed across the network. In most studies, the combination of chitosan and vanillin has been investigated in small sizes (micro/nanoscale and biofilms). In this study, a chitosan-vanillin (CV) hydrogel was studied on a macroscale with a three-dimensional porous structure, and it was compared with chitosan crosslinked with glutaraldehyde (CG) on the same scale. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (FE-SEM) used to identify the bonds formed and examine the morphology of the hydrogels. The gel content, swelling, porosity, mechanical properties, cell viability (on L929 and mesenchymal cells), and antibacterial activity (against Escherichia coli and Staphylococcus aureus) of the samples were investigated. The results showed that the CV had both gel content and high porosity (>90%), with an interconnected porous network of uniform pore size. The CV hydrogel exhibited good antibacterial activity and cell viability. In terms of mechanical properties, CV has weaker mechanical properties compared to CG in the dry state, while the mechanical properties of CV have more improved in the swollen state compared to CG.

Evaluation of chitosan salt properties in the production of AgNPs materials with antibacterial activity

In this study, water-soluble chitosan salts (chitosan amine sulfopropyl salts) were prepared from chitosan samples with different molecular weights and deacetylation degrees. These soluble-in-water polymer salts allowed us to produce, in an eco-friendly and facile method, silver nanoparticles (AgNPs) with better control on size and polydispersity, even at large silver concentrations than their corresponding chitosan sample. Chitosan salt-based materials (films and scaffolds) were analyzed in terms of antibacterial properties against Staphylococcus aureus ATCC23915 or Pseudomonas aeruginosa ATCC 27853. 3D scaffolds enhanced the effect of the chitosan-AgNPs combination compared to the equivalent films.

Breaking the Photostability and pH Limitation of Halo-Fluoresceins through Chitosan Conjugation.

Halo-fluoresceins are widely used in cell and tissue staining, intracellular sensing, and photodynamic therapy, but their notorious photo-instability and pH dependence restrict their applications, especially in long-term visible light exposure and acidic environments. To overcome these limitations, here a strategy is proposed of conjugating chitosan with the carboxyl group of halo-fluorescein (CS-halofluorescein). The cross-linked polymer chains and the hydrogen-bonding networks of chitosan help shielding out 1 O2 from direct attacking the encapsulated halo-fluoresceins, leading to atwo orders of magnitude lower photobleaching rate. Meanwhile, the condensation of primary amines of chitosan with the carboxyl group on halo-fluorescein blocks the pH-dependent intramolecular spirocyclization, leading to pH-inert fluorescein derivatives. The greatly improved photostability and pH inertness of CS-halofluoresceins can be harvested for aerobic photoredox synthesis and photodynamic bacteria inactivation in extremely acidic media. Moreover, food additive nature of chitosan and erythrosine (TIF) and excellent film-forming property of chitosan allow coating-based light-assisted preservation of perishable fruits, leading to appreciably extended shelf life of fruits (e.g., perishable strawberry, rt: > 3 days; 4°C: > 5 days).

Porous Silica as Drug Carrier for Controlled Delivery of Sulfasalazine: The Effect of Alginate-N, O-Carboxymethyl Chitosan Gel Coating and Amine Functionalization.

The necessity of colon-specific drug delivery systems has been well recognized. Porous silica (PSi) coated with a pH-sensitive, biocompatible, and biodegradable polymer can be useful in colon delivery. In this study, porous silica was synthesized and sulfasalazine was loaded into it to investigate the release rate in a simulated intestinal media. The media was kept at 37°C and pH 6.8 and 7.4, and subjected to continuous ultrasonic waves to simulate body fluid flow. Aqueous alginate and N, O-Carboxymethyl chitosan (NOCC) solutions, with a distinct composition (3% W/V) in different ratios, were prepared and coated on pressed porous silica disks. Porous silica (PSi) was also functionalized by aminopropyltrimethoxysilane grafting and was studied as a potential carrier for the controlled drug release of sulfasalazine. The release was studied in simulated gastric and intestinal media and results show that no burst release occurred in both coated and functionalized samples and the swelling degree of coats at basic and neutral media decreased by the presence of alginate in the network. It is concluded that the coat with a 50:50 ratio can release the colon drugs in 24h at a suitable rate. It is also envisioned that functionalization was a factor boosting drug uptake, however, the release rate was lower in the functionalized samples. This study opens the gates to new ideas for the potential safe and localized delivery of sulfasalazine.

Chitosan-multilayered graphene oxide hybrid beads for Zn 2+ and metoprolol adsorption

Chitosan (CS) hydrogel beads and hybrid beads made of a blending of CS hydrogels and Multilayer Graphene Oxide (MGO) were synthesized. The hybrid beads were prepared by gelation in NaOH solution of a 1 wt% CS acid solution with addition of MGO at either 1.5 wt% or 3 wt% loading rates. Prepared beads were characterized by infrared spectroscopy, thermogravimetric analysis (TGA), scanning electron cryo-microscopy and Brunauer–Emmett–Teller (BET) specific surface area measurements. Zn 2+ and Metoprolol (MTP) adsorption kinetics and isotherms were studied on the pristine and hybrid CS hydrogel beads. The adsorption kinetics of Zn 2+ and MTP in hybrid beads is limited by the diffusion to the MGO sites depending on their accessibility. While pure CS is not efficient for the MTP adsorption, the Langmuir-type isotherms of the 3 wt% MGO hydrogel beads (dose: 5 mg/100 mL) show 163 mg·g -1 maximum adsorption uptake. The MTP adsorption kinetics and isotherm suggest a MTP trapping on the MGO anionic sites (carboxylate groups) by electrostatic interactions. The Zn 2+ adsorption capacities are the highest for the 3 wt% MGO hydrogel beads (236 mg·g -1 ), and only of 40 mg·g -1 for the pure CS beads. The presence of Zn 2+ adsorption sites in the hybrid bead, such as MGO carboxylate groups giving electrostatic interactions, and CS amine groups leading to complexation, provides synergic adsorption effects. The competitive adsorption of Zn 2+ with respect to MTP in equimolar mixture was observed on hybrid beads (dose: 200 mg/100 mL) at 2 mmol·L -1 initial total concentration. At pollutant initial total concentration lower than 1.5 mmol·L -1 , no competition occurs. The regeneration at pH 4 of the hybrid beads toward MTP or Zn 2+ adsorption was found to be 35–40% of the initial adsorption uptake for five adsorption/regeneration cycles.

A fluorinated chitosan-based QuEChERS method for simultaneous determination of 20 organophosphorus pesticide residues in ginseng using GC-MS/MS.

In this study, a new fluorinated methacrylamide (MACF) was synthesized and evaluated as an adsorbent in the dispersive solid-phase extraction for the effective determination and extraction of 20 organophosphorus pesticides (OPPs) from ginseng samples using the QuEChERS (quick, easy, cheap, effective, rugged, safe) method coupled with GC-MS/MS. The properties of MACF were characterized using Fourier-transform infrared spectroscopy, elemental analysis, and high-resolution 19 F NMR. MACF, chitosan, primary and secondary amine, octadecylsilane, graphitized carbon black, Z-Sep, Z-Sep+ , and EMR-Lipid were compared in terms of extraction efficiency. The best results were obtained when MACF was used. Matrix-matched calibration was employed for quantification. All the OPPs exhibited good linearity (r2 > 0.9969) with the concentration at their respective concentration ranges. The limits of detection were 1.5-3.0μg/kg, and the limits of quantification were 5.0-10.0μg/kg. The trueness of the 20 pesticides at four spiked levels ranged from 86.1 to 111.1%, and the relative standard deviation was less than 11.3%. The modified QuEChERS method using MACF as the adsorbent was sensitive, reliable, and cost-effective and could be used for the determination of 20 OPP residues in ginseng.

Synthesis of long chain alkanes via aldol condensation over modified chitosan catalyst and subsequent hydrodeoxygenation

In this paper, jet fuel range alkanes were produced by aldol condensation of furfural and levulinic acid over modified chitosan catalyst and subsequent hydrodeoxygenation. NaOH modified chitosan was developed and used as a solid catalyst in the aldol condensation of furfural and levulinic acid to produce long carbon chain compounds. At room temperature, the total yield of condensation products reached 94.4% over NaOH/CT-4 catalyst. The amine of chitosan plays an important role in the aldol condensation, which reacted with the aldehyde group of the furfural, producing an intermediate Schiff base and promoting the formation of condensation products. This new route avoided the occurrence of side reactions caused by NaOH. Therefore, the yield of the products was greatly increased. Moreover, kinetic analysis of the condensation reaction and the test of catalyst repeatability were also conducted with NaOH/CT-4. The condensation products were further converted to long-chain branched alkanes by hydrodeoxygenation over the 5 wt% Pd/NbOPO4 catalyst. As a potential application, these alkanes could be mixed with and used as the components of jet fuels.

Vanillin-bioglass cross-linked 3D porous chitosan scaffolds with strong osteopromotive and antibacterial abilities for bone tissue engineering

Chitosan scaffolds crosslinked by current methods insufficiently meet the demands of bone tissue engineering applications. We developed a novel effective crosslinking technique by using the natural and safe vanillin together with bioglass microparticles to generate an antibacterial, osteoconductive, and mechanically robust 3D porous chitosan-vanillin-bioglass (CVB) scaffold. In addition to the significantly improved mechanical properties, the CVB scaffolds had high porosity (>90%) and interconnected macroporous structures. Our data suggested that the crosslinking mainly resulted from the Schiff base reactions between the aldehydes of vanillin and amines of chitosan, together with the hydrogen and ionic bonds formed within them. Importantly, the CVB scaffolds not only showed good biocompatibility, bioactivity, and strong antibacterial ability but also significantly promoted osteoblastic differentiation, mineralization in vitro, and ectopic bone formation in vivo. Thus, the CVB scaffolds hold great promise for bone tissue engineering applications based on their robust mechanical properties, osteoconductivity, and antibacterial abilities.

Preparation, characterization and release behavior of chitosan-coated nanoliposomes (chitosomes) containing olive leaf extract optimized by response surface methodology

The online version contains supplementary material available at (10.1007/s13197-021-04972-2).

Antibacterial Effect of Chitosan-Gold Nanoparticles and Computational Modeling of the Interaction between Chitosan and a Lipid Bilayer Model.

Pathogenic bacteria have the ability to develop antibiotic resistance mechanisms. Their action consists mainly in the production of bacterial enzymes that inactivate antibiotics or the appearance of modifications that prevent the arrival of the drug at the target point or the alteration of the target point itself, becoming a growing problem for health systems. Chitosan–gold nanoparticles (Cs-AuNPs) have been shown as effective bactericidal materials avoiding damage to human cells. In this work, Cs-AuNPs were synthesized using chitosan as the reducing agent, and a systematic analysis of the influence of the synthesis parameters on the size and zeta potential of the Cs-AuNPs and their UV-vis spectra was carried out. We used a simulation model to characterize the interaction of chitosan with bacterial membranes, using a symmetric charged bilayer and two different chitosan models with different degrees of the chitosan amine protonation as a function of pH, with the aim to elucidate the antibacterial mechanism involving the cell wall disruption. The Cs-AuNP antibacterial activity was evaluated to check the simulation model.

Study on Preparation of a Chitosan/Vitamin C Complex and Its Properties in Cosmetics

In order to expand the application of chitosan in cosmetics, it was modified with vitamin C to prepare a chitosan/vitamin C complex (CSVC complex), which was characterized using ultraviolet-visual, Fourier transform infrared, and differential scanning calorimetry techniques. Its hygroscopicity, moisture retention, antioxidant and antibacterial activities, and environmental stability were also determined. The results showed that a mass ratio of chitosan to vitamin C of 1:1 that reacted at 25℃ for 90 minutes in a medium of isopropanol–water, away from light, with the unreacted vitamin C being removed by dialysis gave a white powder (CSVC complex) after freeze-drying. The CSVC complex had good water solubility, a viscosity average molecular weight of 233.7 kDa, and a vitamin C content of 22.64%. Structure characterization confirmed that the CSVC complex was composed of the amine (C-2 position) of chitosan and the hydroxyl group (C-3 position) of vitamin C by electrostatic attraction. The complex had a significantly better scavenging effect on hydroxyl free radicals than chitosan, and the minimum inhibitory concentration against Escherichia coli was 5 mg/mL. Its moisturizing and hygroscopic properties were better than chitosan, and its stability was better than that of vitamin C. These results provide the basis for the CSVC complex as a multifunctional raw material for cosmetic use because of its antioxidant, moisturizing, antibacterial, and film-forming properties.

The Pharmaceutical Application of Sulfoxy Amine Chitosan in Design, Development and Evaluation of Transdermal Drug Delivery of Gliclazide

Objective: The aim & objectives of this research work was to explore applicability of our previously synthesized sulfoxy amine chitosan in design, development and evaluation of transdermal drug delivery of Gliclazide.
 Methods: To determine the interaction between excipients used and to find out the nature of drug in the formulation, Fourier transforms infra-red spectroscopy (FTIR) and Differential Scanning Colorimetry (DSC) studies were performed. Gliclazide containing transdermal patch were formulated with help of Sulfoxy Amine Chitosan, HPMC, Penetration enhancer Dimethyl Sulfoxide and Glycerine by using solvent casting method.9 formulations prepared by using 32 full factorial designs the effect of formulation variable was studied on % Moisture Content, Folding endurance, % Cumulative drug release at 12 hrs.Formulated transdermal patches were evaluated for various parameters.
 Results: FTIR & DSC suggest study no drug & polymers interaction .All the prepared transdermal patches were found to be faint yellow in colored, flexible, uniform, smooth, and transparent. The weight of the transdermal patches for different type of formulations ranged between 12.00 ± 0.6 mg & 14.2 ± 0.52 mg. The thickness of the patches varied from 0.171 ± 0.0035 mm to 0.182 ± 0.0026 mm. The moisture content & water vapour transmission rate in the patches ranged from 2.33 to 4.55% & from 0.002246 to 0.003597 mg.cm/cm2 24hrs.XRD diffractogram revealed pure Gliclazide exhibited characteristic high-intensity diffraction peaks & optimized formulation showed three peaks in 2θ= 20.6 28.7 and 38.95 with very weak intensities. Optimized batch F7 showed maximum drug release 98.41%. The folding endurance was lies in between 301 and 359. Optimization study was successfully conducted using 32 factorial designs.
 Conclusion: We concluded that transdermal patches Gliclazide of was successfully formulated with synthesized Sulfoxy Amine Chitosan & evaluated.