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Adsorption characterization of Pb(II) and Cu(II) ions onto chitosan-tripolyphosphate beads: Kinetic, equilibrium and thermodynamic studies

Ngah WS, Fatinathan S

J Environ Manage, 2010 Mar-Apr;91(4):958-69.
PMID: 20044203 DOI: 10.1016/j.jenvman.2009.12.003

Chitosan-tripolyphosphate (CTPP) beads were synthesized, characterized and were used for the adsorption of Pb(II) and Cu(II) ions from aqueous solution. The effects of initial pH, agitation period, adsorbent dosage, different initial concentrations of heavy metal ions and temperature were studied. The experimental data were correlated with the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The maximum adsorption capacities of Pb(II) and Cu(II) ions in a single metal system based on the Langmuir isotherm model were 57.33 and 26.06 mg/g, respectively. However, the beads showed higher selectivity towards Cu(II) over Pb(II) ions in the binary metal system. Various thermodynamic parameters such as enthalpy (DeltaH degrees), Gibbs free energy (DeltaG degrees) and entropy (DeltaS degrees) changes were computed and the results showed that the adsorption of both heavy metal ions onto CTPP beads was spontaneous and endothermic in nature. The kinetic data were evaluated based on the pseudo-first and -second order kinetic and intraparticle diffusion models. Infrared spectra were used to elucidate the mechanism of Pb(II) and Cu(II) ions adsorption onto CTPP beads.

Matched MeSH terms: Chitosan/chemistry*
Adsorption behaviour of Fe(II) and Fe(III) ions in aqueous solution on chitosan and cross-linked chitosan beads

Ngah WS, Ab Ghani S, Kamari A

Bioresour Technol, 2005 Mar;96(4):443-50.
PMID: 15491825

A batch adsorption system was applied to study the adsorption of Fe(II) and Fe(III) ions from aqueous solution by chitosan and cross-linked chitosan beads. The adsorption capacities and rates of Fe(II) and Fe(III) ions onto chitosan and cross-linked chitosan beads were evaluated. Chitosan beads were cross-linked with glutaraldehyde (GLA), epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDE) in order to enhance the chemical resistance and mechanical strength of chitosan beads. Experiments were carried out as function of pH, agitation period, agitation rate and concentration of Fe(II) and Fe(III) ions. Langmuir and Freundlich adsorption models were applied to describe the isotherms and isotherm constants. Equilibrium data agreed very well with the Langmuir model. The kinetic experimental data correlated well with the second-order kinetic model, indicating that the chemical sorption was the rate-limiting step. Results also showed that chitosan and cross-linked chitosan beads were favourable adsorbers.

Matched MeSH terms: Chitosan/chemistry*
Fulltext In Vitro Evaluation of Curcumin-Encapsulated Chitosan Nanoparticles against Feline Infectious Peritonitis Virus and Pharmacokinetics Study in Cats

Ng SW, Selvarajah GT, Hussein MZ, Yeap SK, Omar AR

Biomed Res Int, 2020;2020:3012198.
PMID: 32596292 DOI: 10.1155/2020/3012198

Feline infectious peritonitis (FIP) is an important feline viral disease, causing an overridden inflammatory response that results in a high mortality rate, primarily in young cats. Curcumin is notable for its biological activities against various viral diseases; however, its poor bioavailability has hindered its potential in therapeutic application. In this study, curcumin was encapsulated in chitosan nanoparticles to improve its bioavailability. Curcumin-encapsulated chitosan (Cur-CS) nanoparticles were synthesised based on the ionic gelation technique and were spherical and cuboidal in shape, with an average particle size of 330 nm and +42 mV in zeta potential. The nanoparticles exerted lower toxicity in Crandell-Rees feline kidney (CrFK) cells and enhanced antiviral activities with a selective index (SI) value three times higher than that of curcumin. Feline-specific bead-based multiplex immunoassay and qPCR were used to examine their modulatory effects on proinflammatory cytokines, including tumour necrosis factor (TNF)α, interleukin- (IL-) 6, and IL-1β. There were significant decrements in IL-1β, IL-6, and TNFα expression in both curcumin and Cur-CS nanoparticles. Based on the multiplex immunoassay, curcumin and the Cur-CS nanoparticles could lower the immune-related proteins in FIP virus (FIPV) infection. The single- and multiple-dose pharmacokinetics profiles of curcumin and the Cur-CS nanoparticles were determined by high-performance liquid chromatography (HPLC). Oral delivery of the Cur-CS nanoparticles to cats showed enhanced bioavailability with a maximum plasma concentration (Cmax) value of 621.5 ng/mL. Incorporating chitosan nanoparticles to deliver curcumin improved the oral bioavailability and antiviral effects of curcumin against FIPV infection. This study provides evidence for the potential of Cur-CS nanoparticles as a supplementary treatment of FIP.

Matched MeSH terms: Chitosan/chemistry*
Agarose-chitosan-C18 film micro-solid phase extraction combined with high performance liquid chromatography for the determination of phenanthrene and pyrene in chrysanthemum tea samples

Ng NT, Sanagi MM, Wan Ibrahim WN, Wan Ibrahim WA

Food Chem, 2017 May 01;222:28-34.
PMID: 28041555 DOI: 10.1016/j.foodchem.2016.11.147

Agarose-chitosan-immobilized octadecylsilyl-silica (C18) film micro-solid phase extraction (μSPE) was developed and applied for the determination of phenanthrene (PHE) and pyrene (PYR) in chrysanthemum tea samples using high performance liquid chromatography-ultraviolet detection (HPLC-UV). The film of blended agarose and chitosan allows good dispersion of C18, prevents the leaching of C18 during application and enhances the film mechanical stability. Important μSPE parameters were optimized including amount of sorbent loading, extraction time, desorption solvent and desorption time. The matrix match calibration curves showed good linearity (r⩾0.994) over a concentration range of 1-500ppb. Under the optimized conditions, the proposed method showed good limits of detection (0.549-0.673ppb), good analyte recoveries (100.8-105.99%) and good reproducibilities (RSDs⩽13.53%, n=3) with preconcentration factors of 4 and 72 for PHE and PYR, respectively.

Matched MeSH terms: Chitosan/chemistry
Purification of lysozyme from chicken egg white using nanofiber membrane immobilized with Reactive Orange 4 dye

Ng IS, Song CP, Ooi CW, Tey BT, Lee YH, Chang YK

Int J Biol Macromol, 2019 Aug 01;134:458-468.
PMID: 31078593 DOI: 10.1016/j.ijbiomac.2019.05.054

Nanofiber membrane chromatography integrates liquid membrane chromatography and nanofiber filtration into a single-step purification process. Nanofiber membrane can be functionalised with affinity ligands for promoting binding specificity of membrane. Dye molecules are a good affinity ligand for nanofiber membrane due to their low cost and high binding affinity. In this study, a dye-affinity nanofiber membrane (P-Chitosan-Dye membrane) was prepared by using polyacrylonitrile nanofiber membrane modified with chitosan molecules and immobilized with dye molecules. Reactive Orange 4, commercially known as Procion Orange MX2R, was found to be the best dye ligand for membrane chromatography. The binding capacity of P-Chitosan-Dye membrane for lysozyme was investigated under different operating conditions in batch mode. Furthermore, desorption of lysozyme using the P-Chitosan-Dye membrane was evaluated systematically. The recovery percentage of lysozyme was found to be ~100%. The optimal conditions obtained from batch-mode study were adopted to develop a purification process to separate lysozyme from chicken egg white. The process was operated continuously using the membrane chromatography and the characteristic of the breakthrough curve was evaluated. At a lower flow rate (i.e., 0.1 mL/min), the total recovery of lysozyme and purification factor of lysozyme were 98.59% and 56.89 folds, respectively.

Matched MeSH terms: Chitosan/chemistry
Comparative Efficacy of Chitosan, Pectin Based Mesalamine Colon Targeted Drug Delivery Systems on TNBS-induced IBD Model Rats

Newton AMJ, Lakshmanan P

Antiinflamm Antiallergy Agents Med Chem, 2020;19(2):113-127.
PMID: 30657050 DOI: 10.2174/1871523018666190118112230

OBJECTIVE: A number of natural polymer-based drug delivery systems targeting the colon are reported for different applications. Most of the research is based on the class of natural polymers such as polysaccharides. This study compares the anti-inflammatory effect of different polysaccharide based tablets on IBD when a drug carrier is targeted to the colon as matrix and coated systems.
METHODS: The TNBS induced IBD Wistar rats were used as a model for the study. The microscopic and macroscopic parameters were studied in detail. Almost all the important IBD parameters were reported in this work.
RESULTS: The results demonstrated that the polysaccharides are efficient in carrying the drugs to the colon. Reduction in the level of ulcer index (UI), Myeloperoxidase (MPO), and Malondialdehyde MDA, confirmed the inhibitory activity on the development of Reactive oxygen species (ROS). The increased level of Tumor necrosis factor (TNFα) an expression of colonic inducible nitric oxide synthase (iNOS) was lowered in treatments as compared to TNBS control.
CONCLUSION: The different polymer-based mesalamine (DPBM) confirmed the efficient anti- inflammatory activity on IBD induced rats. The increased level of glutathione (GSH), and superoxide dismutase (SOD) also confirmed the effective anti-inflammatory effect. A significant decrease in the ulcer score and ulcer area was reported. The investigation revealed that chitosan is superior to pectin in IBD treatment likewise polysaccharide-based matrix systems are superior to the coated system.

Matched MeSH terms: Chitosan/chemistry
Quantitative characterization of chitosan in the skin by Fourier-transform infrared spectroscopic imaging and ninhydrin assay: application in transdermal sciences

Nawaz A, Wong TW

J Microsc, 2016 07;263(1):34-42.
PMID: 26695532 DOI: 10.1111/jmi.12371

The chitosan has been used as the primary excipient in transdermal particulate dosage form design. Its distribution pattern across the epidermis and dermis is not easily accessible through chemical assay and limited to radiolabelled molecules via quantitative autoradiography. This study explored Fourier-transform infrared spectroscopy imaging technique with built-in microscope as the means to examine chitosan molecular distribution over epidermis and dermis with the aid of histology operation. Fourier-transform infrared spectroscopy skin imaging was conducted using chitosan of varying molecular weights, deacetylation degrees, particle sizes and zeta potentials, obtained via microwave ligation of polymer chains at solution state. Both skin permeation and retention characteristics of chitosan increased with the use of smaller chitosan molecules with reduced acetyl content and size, and increased positive charge density. The ratio of epidermal to dermal chitosan content decreased with the use of these chitosan molecules as their accumulation in dermis (3.90% to 18.22%) was raised to a greater extent than epidermis (0.62% to 1.92%). A larger dermal chitosan accumulation nonetheless did not promote the transdermal polymer passage more than the epidermal chitosan. A small increase in epidermal chitosan content apparently could fluidize the stratum corneum and was more essential to dictate molecular permeation into dermis and systemic circulation. The histology technique aided Fourier-transform infrared spectroscopy imaging approach introduces a new dimension to the mechanistic aspect of chitosan in transdermal delivery.

Matched MeSH terms: Chitosan/chemistry
Chitosan-Carboxymethyl-5-Fluorouracil-Folate Conjugate Particles: Microwave Modulated Uptake by Skin and Melanoma Cells

Nawaz A, Wong TW

J Invest Dermatol, 2018 11;138(11):2412-2422.
PMID: 29857069 DOI: 10.1016/j.jid.2018.04.037

5-Fluorouracil delivery profiles in the form of chitosan-folate submicron particles through skin and melanoma cells in vitro were examined using microwaves as the penetration enhancer. The in vivo pharmacokinetic profile of 5-fluorouracil was also determined. Chitosan-carboxymethyl-5-fluorouracil-folate conjugate was synthesized and processed into submicron particles by spray-drying technique. The size, zeta potential, morphology, drug content, and drug release, as well as skin permeation and retention, pharmacokinetics, in vitro SKMEL-28 melanoma cell line cytotoxicity, and intracellular trafficking profiles of drug/particles, were examined as a function of skin/melanoma cell treatment by microwaves at 2,450 MHz for 5 + 5 minutes. The level of skin drug/particle retention in vitro and in vivo increased in skin treated by microwaves. This was facilitated by the drug conjugating to chitosan and microwaves fluidizing both the protein and lipid domains of epidermis and dermis. The uptake of chitosan-folate particles by melanoma cells was mediated via lipid raft route. It was promoted by microwaves, which fluidized the lipid and protein regimes of the cell membrane, and this increased drug cytotoxicity. In vivo pharmacokinetic study indicated skin treatment by microwave-enhanced drug retention but not permeation. The combination of microwaves and submicron particles synergized skin drug retention and intracellular drug delivery.

Matched MeSH terms: Chitosan/chemistry
Microwave as skin permeation enhancer for transdermal drug delivery of chitosan-5-fluorouracil nanoparticles

Nawaz A, Wong TW

Carbohydr Polym, 2017 Feb 10;157:906-919.
PMID: 27988008 DOI: 10.1016/j.carbpol.2016.09.080

This study investigated transdermal drug delivery mechanisms of chitosan nanoparticles with the synergistic action of microwave in skin modification. Chitosan nanoparticles, with free or conjugated 5-fluorouracil, were prepared by nanospray-drying technique. Their transdermal drug delivery profiles across untreated and microwave-treated skins (2450MHz 5min, 5+5min; 3985MHz 5min) were examined. Both constituent materials of nanoparticles and drug encapsulation were required to succeed transdermal drug delivery. The drug transport was mediated via nanoparticles carrying drug across the skin and/or diffusion of earlier released drug molecules from skin surfaces. The drug/nanoparticles transport was facilitated through constituent nanoparticles and microwave fluidizing protein/lipid domains of epidermis and dermis (OH, NH, CH, CN) and dermal trans-to-gauche lipid conformational changes. The microwave induced marked changes to the skin ceramide content homogeneity. The chitosan nanoparticles largely affected the palmitic acid and keratin domains. Combined microwave and nanotechnologies synergize transdermal drug delivery.

Matched MeSH terms: Chitosan/chemistry
Adsorption of malachite green from aqueous solution by using novel chitosan ionic liquid beads

Naseeruteen F, Hamid NSA, Suah FBM, Ngah WSW, Mehamod FS

Int J Biol Macromol, 2018 Feb;107(Pt A):1270-1277.
PMID: 28965968 DOI: 10.1016/j.ijbiomac.2017.09.111

Chitosan ionic liquid beads were prepared from chitosan and 1-butyl-3-methylimidazolium based ionic liquids to remove Malachite Green (MG) from aqueous solutions. Batch adsorption experiments were carried out as a function of initial pH, adsorbent dosage, agitation time and initial MG concentration. The optimum conditions were obtained at pH 4.0, 0.008g of adsorbent dosage and 20min of agitation time were utilized in the kinetic and isotherm studies. Three kinetic models were applied to analyze the kinetic data and pseudo-second order was found to be the best fitted model with R2>0.999. In order to determine the adsorption capacity, the sorption data were analyzed using the linear form of Langmuir, Freundlich and Temkin equations. The isotherm was best fitted by Langmuir isotherm model. The maximum adsorption capacity (qmax) obtained from Langmuir isotherm for two chitosan beads 1-butyl-3-methylimidazolium acetate A and 1-butyl-3-methylimidazolium B are 8.07mgg-1 and 0.24mgg-1 respectively.

Matched MeSH terms: Chitosan/chemistry*
An Evaluation of Curcumin-Encapsulated Chitosan Nanoparticles for Transdermal Delivery

Nair RS, Morris A, Billa N, Leong CO

AAPS PharmSciTech, 2019 Jan 10;20(2):69.
PMID: 30631984 DOI: 10.1208/s12249-018-1279-6

Curcumin-loaded chitosan nanoparticles were synthesised and evaluated in vitro for enhanced transdermal delivery. Zetasizer® characterisation of three different formulations of curcumin nanoparticles (Cu-NPs) showed the size ranged from 167.3 ± 3.8 nm to 251.5 ± 5.8 nm, the polydispersity index (PDI) values were between 0.26 and 0.46 and the zeta potential values were positive (+ 18.1 to + 20.2 mV). Scanning electron microscopy (SEM) images supported this size data and confirmed the spherical shape of the nanoparticles. All the formulations showed excellent entrapment efficiency above 80%. FTIR results demonstrate the interaction between chitosan and sodium tripolyphosphate (TPP) and confirm the presence of curcumin in the nanoparticle. Differential scanning calorimetry (DSC) studies of Cu-NPs indicate the presence of curcumin in a disordered crystalline or amorphous state, suggesting the interaction between the drug and the polymer. Drug release studies showed an improved drug release at pH 5.0 than in pH 7.4 and followed a zero order kinetics. The in vitro permeation studies through Strat-M® membrane demonstrated an enhanced permeation of Cu-NPs compared to aqueous curcumin solution (p ˂ 0.05) having a flux of 0.54 ± 0.03 μg cm-2 h-1 and 0.44 ± 0.03 μg cm-2 h-1 corresponding to formulations 5:1 and 3:1, respectively. The cytotoxicity assay on human keratinocyte (HaCat) cells showed enhanced percentage cell viability of Cu-NPs compared to curcumin solution. Cu-NPs developed in this study exhibit superior drug release and enhanced transdermal permeation of curcumin and superior percentage cell viability. Further ex vivo and in vivo evaluations will be conducted to support these findings.

Matched MeSH terms: Chitosan/chemistry
An inhibitory action of chitosan nanoparticles against pathogenic bacteria and fungi and their potential applications as biocompatible antioxidants

MubarakAli D, LewisOscar F, Gopinath V, Alharbi NS, Alharbi SA, Thajuddin N

Microb Pathog, 2018 Jan;114:323-327.
PMID: 29229504 DOI: 10.1016/j.micpath.2017.11.043

Chitosan is the second most abundant polymer obtained from the byproduct of seafood. Chitosan and its derivatives and chitosan loaded drugs are the recent area of interest against microbial pathogenesis. The cationic chitosan nanoparticles (ChNPs) interact with the anionic surfaces of the microbial cell membrane, which promotes antimicrobial activity. Although, ChNPs are potential against pathogenic microbes, selection of adaptable, suitable and cost effective synthesis method is much important. In the present study, ChNPs were synthesized adopting ionic gelation using sodium tripolyphosphate as a cross linking agent and characterized by FTIR, DLS, SEM and TEM analysis. ChNPs were investigated for antimicrobial activity against bacterial (Escherichia coli and Staphylococcus aureus) and fungal (Candida albicans) pathogens. ChNPs showed bactericidal activity at the lower minimum inhibitory concentration of about 40-80 μg mL-1. Interestingly, ChNPs exhibits biocompatible antioxidant property by inhibiting DPPH free radicals at 76% and also proven to be a potential candidate against the microbial pathogenesis with an inevitable applications in biomedicine.

Matched MeSH terms: Chitosan/chemistry
Fulltext Synthesis and ultraviolet visible spectroscopy studies of chitosan capped gold nanoparticles and their reactions with analytes

Mohd Sultan N, Johan MR

ScientificWorldJournal, 2014;2014:184604.
PMID: 25215315 DOI: 10.1155/2014/184604

Gold nanoparticles (AuNPs) had been synthesized with various molarities and weights of reducing agent, monosodium glutamate (MSG), and stabilizer chitosan, respectively. The significance of chitosan as stabilizer was distinguished through transmission electron microscopy (TEM) images and UV-Vis absorption spectra in which the interparticles distance increases whilst retaining the surface plasmon resonance (SPR) characteristics peak. The most stable AuNPs occurred for composition with the lowest (1 g) weight of chitosan. AuNPs capped with chitosan size stayed small after 1 month aging compared to bare AuNPs. The ability of chitosan capped AuNPs to uptake analyte was studied by employing amorphous carbon nanotubes (α-CNT), copper oxide (Cu2O), and zinc sulphate (ZnSO4) as the target material. The absorption spectra showed dramatic intensity increased and red shifted once the analyte was added to the chitosan capped AuNPs.

Matched MeSH terms: Chitosan/chemistry*
Fulltext Chitosan dermal substitute and chitosan skin substitute contribute to accelerated full-thickness wound healing in irradiated rats

Mohd Hilmi AB, Halim AS, Jaafar H, Asiah AB, Hassan A

Biomed Res Int, 2013;2013:795458.
PMID: 24324974 DOI: 10.1155/2013/795458

Wounds with full-thickness skin loss are commonly managed by skin grafting. In the absence of a graft, reepithelialization is imperfect and leads to increased scar formation. Biomaterials can alter wound healing so that it produces more regenerative tissue and fewer scars. This current study use the new chitosan based biomaterial in full-thickness wound with impaired healing on rat model. Wounds were evaluated after being treated with a chitosan dermal substitute, a chitosan skin substitute, or duoderm CGF. Wounds treated with the chitosan skin substitute showed the most re-epithelialization (33.2 ± 2.8%), longest epithelial tongue (1.62 ± 0.13 mm), and shortest migratory tongue distance (7.11 ± 0.25 mm). The scar size of wounds treated with the chitosan dermal substitute (0.13 ± 0.02 cm) and chitosan skin substitute (0.16 ± 0.05 cm) were significantly decreased (P < 0.05) compared with duoderm (0.45 ± 0.11 cm). Human leukocyte antigen (HLA) expression on days 7, 14, and 21 revealed the presence of human hair follicle stem cells and fibroblasts that were incorporated into and surviving in the irradiated wound. We have proven that a chitosan dermal substitute and chitosan skin substitute are suitable for wound healing in full-thickness wounds that are impaired due to radiation.

Matched MeSH terms: Chitosan/chemistry
Physicochemical modification of chitosan with fly ash and tripolyphosphate for removal of reactive red 120 dye: Statistical optimization and mechanism study

Mohammed IA, Jawad AH, Abdulhameed AS, Mastuli MS

Int J Biol Macromol, 2020 Oct 15;161:503-513.
PMID: 32534088 DOI: 10.1016/j.ijbiomac.2020.06.069

Chitosan (CS) was physically modified with fly ash (FA) powder and subjected to chemical cross-linking reaction with tripolyphosphate (TPP) to produce a cross-linked CS-TPP/FA composite as adsorbent for removal of reactive orange 120 (RR120) dye. Different ratios of FA such as 25% FA particles (CS-TPP/FA-25) and 50% FA particles (CS-TPP/FA-50) were loaded into the molecular structure of CS-TPP. Box-Behnken design (BBD) was applied to optimize the input variables that affected the synthesis of the adsorbent and the adsorption of RR120 dye. These variables included FA loading (A: 0-50%), adsorbent dose (B: 0.04-0.1 g), solution pH (C: 4-10), temperature (D: 30 °C-60 °C), and time (E: 30-90 min). Results revealed that the highest removal (88.8%) of RR120 dye was achieved by CS-TPP/FA-50 at adsorbent dosage of 0.07 g, solution of pH 4, temperature of 45 °C, and time of 60 min. The adsorption equilibrium was described by the Freundlich model, with 165.8 mg/g at 45 °C as the maximum adsorption capacity of CS-TPP/FA-50 for RR120 dye. This work introduces CS-TPP/FA-50 as an ideal composite adsorbent for removal of textile dyes from the aqueous environment.

Matched MeSH terms: Chitosan/chemistry*
Controlled release studies through chitosan-based hydrogel synthesized at different polymerization stages

Md Rasib SZ, Md Akil H, Khan A, Abdul Hamid ZA

Int J Biol Macromol, 2019 May 01;128:531-536.
PMID: 30708001 DOI: 10.1016/j.ijbiomac.2019.01.190

An earlier study showed that the behaviour of chitosan-poly(methacrylic acid‑co‑N‑isopropylacrylamide) [chitosan‑p(MAA‑co‑NIPAM)] hydrogels synthesized at different reaction times are affected with regard to their pH and temperature sensitivities. The study was continued in this paper to identify the effects of different reaction times on the degradation, efficiency of rifampicin (Rif) loading and the Rif release profile under two different pH conditions (acidic and basic). The results that were obtained showed that the hydrogel had a faster degradation rate in the acidic condition than in the basic condition, where there was a loss of approximately 50% and 20%, respectively in its original weight within two weeks. The Rif loading efficiency was within 50% and the drug release was controlled by characteristics that were developed beyond the polymerization stages of the synthesis. Therefore, the reaction time for the synthesis of the hydrogel can be considered as a way to control the behaviour of the hydrogel as well as to modify the drug release profile in the chitosan‑p(MAA‑co‑NIPAM) hydrogel.

Matched MeSH terms: Chitosan/chemistry*
Cross-linked chitosan/sepiolite composite for the adsorption of methylene blue and reactive orange 16

Marrakchi F, Khanday WA, Asif M, Hameed BH

Int J Biol Macromol, 2016 Dec;93(Pt A):1231-1239.
PMID: 27663552 DOI: 10.1016/j.ijbiomac.2016.09.069

Cross-linked chitosan/sepiolite composite was prepared from sepiolite clay and chitosan, and was cross-linked using epichlorohydrin. Among the various weight ratio percentage of chitosan and sepiolite clay composites, CS50SP50 was selected as the best adsorbent for both methylene blue (MB) and reactive orange 16 (RO 16). At an optimum adsorbent dosage of 0.2g/100mL, the effects of initial dye concentration (25-400mg/L) and pH (3-11) on MB and RO 16 adsorption onto CS50SP50 composite were studied. Monolayer adsorption capacities of CS50SP50 composite for MB and RO 16 were 40.986mg/g and 190.965mg/g, respectively at 30°C. Freundlich, Langmuir and Temkin isotherms applied on the adsorption data for both the dyes reveal that data fitted best for Freundlich model. For both the dyes pseudo-second-order kinetics were found to describe the adsorption process better than pseudo-first-order kinetics. The adsorption capacity of CS50SP50 composite for both the dyes was found better compared to previous studies thus making it potentially low-cost adsorbent for removal of both cationic and reactive dyes.

Matched MeSH terms: Chitosan/chemistry*
Mesoporous-activated carbon prepared from chitosan flakes via single-step sodium hydroxide activation for the adsorption of methylene blue

Marrakchi F, Ahmed MJ, Khanday WA, Asif M, Hameed BH

Int J Biol Macromol, 2017 May;98:233-239.
PMID: 28147233 DOI: 10.1016/j.ijbiomac.2017.01.119

In this work, mesoporous-activated carbon (CSAC) was prepared from chitosan flakes (CS) via single-step sodium hydroxide activation for the adsorption of methylene blue (MB). CSAC was prepared using different impregnation ratios of NaOH:CS (1:1, 2:1, 3:1, and 4:1) at 800°C for 90min. The adsorption performance of CSAC was evaluated for MB at different adsorption variables, such MB initial concentrations (25-400mg/L), solution pH (3-11), and temperature (30-50°C). The adsorption isotherm data of CSAC-MB were well fitted to Langmuir model with a maximum adsorption capacity 143.53mg/g at 50°C. Best representation of kinetic data was obtained by the pseudo-second order model. CSAC exhibited excellent adsorption uptake for MB and can potentially be used for other cationic dyes.

Matched MeSH terms: Chitosan/chemistry*
Enzymatic esterification of eugenol and benzoic acid by a novel chitosan-chitin nanowhiskers supported Rhizomucor miehei lipase: Process optimization and kinetic assessments

Manan FMA, Attan N, Zakaria Z, Keyon ASA, Wahab RA

Enzyme Microb Technol, 2018 Jan;108:42-52.
PMID: 29108626 DOI: 10.1016/j.enzmictec.2017.09.004

A biotechnological route via enzymatic esterification was proposed as an alternative way to synthesize the problematic anti-oxidant eugenyl benzoate. The new method overcomes the well-known drawbacks of the chemical route in favor of a more sustainable reaction process. The present work reports a Box-Behnken design (BBD) optimization process to synthesize eugenyl benzoate by esterification of eugenol and benzoic acid catalyzed by the chitosan-chitin nanowhiskers supported Rhizomucor miehei lipase (RML-CS/CNWs). Effects of four reaction parameters: reaction time, temperature, substrate molar ratio of eugenol: benzoic acid and enzyme loading were assessed. Under optimum conditions, a maximum conversion yield as high as 66% at 50°C in 5h using 3mg/mL of RML-CS/CNWs, and a substrate molar ratio (eugenol: benzoic acid) of 3:1. Kinetic assessments revealed the RML-CS/CNWs catalyzed the reaction via a ping-pong bi-bi mechanism with eugenol inhibition, characterized by a Vmax of 3.83mMmin-1. The Michaelis-Menten constants for benzoic acid (Km,A) and eugenol (Km,B) were 34.04 and 138.28mM, respectively. The inhibition constant for eugenol (Ki,B) was 438.6mM while the turnover number (kcat) for the RML-CS/CNWs-catalyzed esterification reaction was 40.39min-1. RML-CS/CNWs were reusable up to 8 esterification cycles and showed higher thermal stability than free RML.

Matched MeSH terms: Chitosan/chemistry
Fulltext Evaluation of Antitumor Efficacy of Chitosan-Tamarind Gum Polysaccharide Polyelectrolyte Complex Stabilized Nanoparticles of Simvastatin

Malviya R, Raj S, Fuloria S, Subramaniyan V, Sathasivam K, Kumari U, et al.

Int J Nanomedicine, 2021;16:2533-2553.
PMID: 33824590 DOI: 10.2147/IJN.S300991

PURPOSE: The present study was intended to fabricate chitosan (Ch)-tamarind gum polysaccharide (TGP) polyelectrolyte complex stabilized cubic nanoparticles of simvastatin and evaluate their potential against human breast cancer cell lines.
MATERIALS AND METHODS: The antisolvent precipitation method was used for formulation of nanoparticles. Factorial design (32) was utilized as a tool to analyze the effect of Ch and TGP concentration on particle size and entrapment efficiency of nanoparticles.
RESULTS: Formulated nanoparticles showed high entrapment efficiency (67.19±0.42-83.36±0.23%) and small size (53.3-383.1 nm). The present investigation involved utilization of two biological membranes (egg and tomato) as biological barriers for drug release. The study revealed that drug release from tomato membranes was retarded (as compared to egg membranes) but the release pattern matched that of egg membranes. All formulations followed the Baker-Lansdale model of drug release irrespective of the two different biological barriers. Stability studies were carried out for 45 days and exhibited less variation in particle size as well as a reduction in entrapment efficiency. Simvastatin loaded PEC stabilized nanoparticles exhibited better control on growth of human breast cancer cell lines than simple simvastatin. An unusual anticancer effect of simvastatin nanoparticles is also supported by several other research studies.
CONCLUSION: The present study involves first-time synthesis of Ch-TGP polyelectrolyte complex stabilized nanoparticles of simvastatin against MCF-7 cells. It recommends that, in future, theoretical modeling and IVIVC should be carried out for perfect designing of delivery systems.

Matched MeSH terms: Chitosan/chemistry*

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