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Combatting Pathogenic Bacteria with Synthetic Immunotherapeutics from chitosan:Antibody Recruiting at Engineered Bacterial Surface with Peptidoglycan Analogs

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CCS Chemistry 2024年第6期6卷 1448-1457页

作者： Yuan Xu Shihao Song Hongwei Duan Yinyue Deng Xue-Wei Liu School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637371 Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikou 570228 School of Pharmaceutical Sciences(Shenzhen) Shenzhen Campus of Sun Yat-sen UniversitySun Yat-sen UniversityShenzhen 518107

The emergence of microbial drug resistance,coupled with the paucity of new antibiotics poses an impending threat to public health.In this work,we drew inspiration from synthetic peptidoglycan oligomers and successfully constructed antibody-recruiting peptidoglycan analogs,2a-d,with excellent safety profiles and high efficiencies in recruiting antibodies across different conditions.Further,we demonstrated that these peptidoglycan analogs could be readily incorporated into bacteria cell walls,whereby both simple monoclonal and pooled human serum antibodies effectively congregated to the surfaceengineered bacteria,leading to the complete extermination of the engineered bacterial cells both in vitro and in vivo.Our peptidoglycan analog agents for recruiting endogenous antibodies to combat pathogenic bacteria enable further development of promising broad-spectrum immunotherapeutics.

关键词： chitosan bacterial infection endogenous antibodies bacterial surface engineering peptidoglycan analogs

Fabrication and evaluation of carboxymethyl guar gum-chitosan interpenetrating polymer network (IPN) nanoparticles for controlled drug delivery

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Medicine in Novel Technology and Devices 2024年第2期22卷 73-79页

作者： Chandrani Roy Arijit Gandhi Sreejan Manna Sougata Jana Department of Pharmaceutics Gupta College of Technological SciencesAshram MoreG.T.RoadAsansol713301West BengalIndia Department of Pharmaceutical Technology Brainware UniversityBarasatKolkataWest Bengal700125India Department of Health and Family Welfare Directorate of Health ServicesKolkataIndia

Guar gum(GG)has drawn more interest from researchers in the last several decades for the controlled delivery of drugs.The aim of the research is to fabricate and evaluate an interpenetrating polymer network(IPN)based nanocarriers system employing chemically modified GG to achieve controlled release of drug.In present study,we have reported the synthesis of carboxymethyl GG-chitosan IPN nanoparticles for controlled release of metformin hydrochloride.Carboxymethyl guar gum(CMGG)was synthesized and employed for developing IPN nanoparticles in combination with chitosan in varying polymeric ratios.A cross-linking agent,sodium tripolyphosphate(Na-TPP)was used for the synthesis of IPN colloidal suspension of nanoparticles which was lyophilized to obtain nanoparticles.The carboxymethylation of GG was confirmed through Fourier transform infra-red spectroscopy.The mean particle size was 440.6 nm indicating a polydispersity index of 0.528.The drug entrapment efficiency was found to vary between 67.461.64%to 88.232.02%.The differential scanning calorimetry study revealed the presence of amorphous metformin hydrochloride as a homogenous dispersion in nanoparticles(NPs)matrix.In vitro drug release study indicated controlled release ability of developed IPN matrix.A2 formulation(chitosan:CMGG-1:1)exhibited 78.110.27%release after 8 h.Antidiabetic evaluation performed in alloxan-treated diabetic rat model exhibited a prolonged hypoglycemic efficacy over 6 h,for A2 formulation treated group,compared to the group receiving only metformin HCl,which demonstrated a reduction in blood glucose levels for up to 4 h.The study findings demonstrated the efficacy of the CMGG-chitosan based IPN nanoparticulate system for sustained delivery of therapeutic agents.

关键词： Carboxymethyl guar gum chitosan Interpenetrating polymer network Nanoparticles Controlled release Metformin hydrochloride

Simple preparation of C(CS)/g-C_(3)N_(4)/Co carbon aerogel and its catalytic performance for ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 186-196页

作者： Yujie Yan Bo Jin Rufang Peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

Biomass chitosan(CS)was used as a template,graphitic phase carbon nitride(g-C_(3)N_(4))with high nitrogen content and certain catalytic activity was used as a dopant,and nano-transition metal cobalt(Co)was used as a catalytic center point.The carbon aerogel(C(CS)/g-C_(3)N_(4)/Co)with a three-dimensional network-like structure was prepared by assembling the three materials through experimental operations such as freeze-drying and high-temperature carbonization.It was demonstrated by scanning and transmission characterization that the CS in the carbon aerogel could provide more active sites for the cobalt nanoparticles,and the doping of graphite-phase carbon nitride as a template dispersed the cobalt nanoparticles and changed the conductivity of the CS.To investigate the catalytic effect of carbon aerogel on ammonium perchlorate(AP),it was investigated by differential thermal analyzer and TG thermal analysis.This carbon aerogel was very effective in catalyzing AP,and the 10 wt% content of the catalyst reduced the AP pyrolysis peak from 703.9 to 595.5 K.And to further investigate the synergistic effect of the three materials,further carbon aerogels such as C(CS)/Co,g-C_(3)N_(4)/Co were prepared and applied to catalyze AP,and the same ratio reduced the AP pyrolysis peak by 98.1℃ and 97.7℃.This result indicates a synergistic effect of the assembly of the three materials.

关键词： g-C_(3)N_(4) chitosan Co Ammonium perchlorate Pyrolysis kinetics

From common biomass materials to high-performance tissue engineering scaffold: Biomimetic preparation, properties characterization, in vitro and in vivo evaluations

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Journal of Bioresources and Bioproducts 2024年第2期9卷 185-196页

作者： Zongpu Xu Fang He Jing Yu Zhangze Yang Yu Zhu Rong Liao Ruyin Lyu Mei Yang Liangjun Zhu Mingying Yang Institute of Applied Bioresources College of Animal SciencesZhejiang UniversityHangzhou 310058China Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province Zhejiang UniversityHangzhou 310058China Department of Neurosurgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Converting common biomass materials to high-performance biomedical products could not only reduce the environmental pressure associated with the large-scale use of synthetic materials,but also increase the economic value.chitosan as a very promising candidate has drawn considerable attention owing to its abundant sources and remarkable bioactivities.However,pure chitosan materials usually exhibit insufficient mechanical properties and excessive swelling ratio,which seriously affected their in vivo stability and integrity when applied as tissue engineering scaf-folds.Thus,simultaneously improving the mechanical strength and biological compatibility of pure chitosan(CS)scaffolds becomes very important.Here,inspired by the fiber-reinforced con-struction of natural extracellular matrix and the porous structure of cancellous bone,we built silk microfibers/chitosan composite scaffolds via ice-templating technique.This biomimetic strategy achieved 500%of mechanical improvement to pure chitosan,and meanwhile still maintaining high porosity(>87%).In addition,the increased roughness of chitosan pore walls by embedded silk microfibers significantly promoted cell adhesion and proliferation.More importantly,after subcutaneous implantation in mice for four weeks,the composite scaffold showed greater struc-tural integrity,as well as better collagenation,angiogenesis,and osteogenesis abilities,suggesting its great potential in biomedicine.

关键词： chitosan Biomimetic strategy Fiber-reinforced composite Mechanical property Biocompatibility

Extraction, Production and Quality Evaluation of Margarine from Oil Extracted from Waste Biomass Peels of Avocado and Virgin Coconut Oil, Using chitosan from Reared Shells as Preservative

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 142-168页

作者： Suh-Ndale Svetlana Miyanui Pride Ndasi Ngwasiri Wiyeh Claudette Bakisu Muala Noumo Thierry Ngangmou Wilson Agwanande Ambindei Martin Benoit Ngassoum Department of Nutrition Food and Bioresource Technology College of Technology University of Bamenda Bamenda Cameroon Department of Process Engineering ENSAI University of Ngaoundere Ngaoundere Cameroon Department of Applied Chemistry ENSAI University of Ngaoundere Ngaoundere Cameroon

The production and consumption of avocado pears generates tons of wastes, mainly the pear peels which are usually discarded, although they have been reported to contain important phyto-chemicals with biological activities. The adverse health effect associated with the consumption of saturated lipid based foods has ignited research on reformulation of lipid based foods to eliminate Trans Fatty Acids (TFAs). This study was thus aimed at the extraction and characterization of oil from Avocado Peels (APO) and evaluation of the quality of margarine produced from it. Five verities of pear were used for oil extraction by soxhlet method and physiochemical, oxidative, functional and antioxidant characterization was done. Margarines were formulated using a central composite design using oil blends of APO and Virgin Coconut Oil (VCO) with an oil ratio of 10:90, 40:60, 70:30 respectively, varied blending speed, blending time, and chitosan concentration. Samples were characterized and the effect of process parameters on the physiochemical and functional properties of the margarine studied. Optimized conditions were used to produce samples for sensory evaluation. Color, spreadability, aroma, taste and general acceptability was evaluated using ranking difference test. The results showed that the yield, density, and iodine values of APOs oils ranged from 14.91 ± 0.18 to 11.76 ± 0.46;0.93 ± 0.001 to 0.99 ± 0.1;46.63 ± 1.70 to 52.4 ± 0.63, their acid values, TBA and PV values ranged from 1.42 ± 0.39 to 1.97 ± 0.5;0.11 ± 0.002 to 0.18 ± 0.04;and 2.72 ± 0.14 to 4.43 ± 0.36 respectively, with Brogdon avocado peel variety having the overall best properties prepared blends of trans-free APO margarines showed that increase in APO ratio decreased melting point, increased oxidative stability and reduced moisture content of margarine samples. chitosan addition leads to decrease moisture content and increase functional properties. VCO lead to increase in phenolic and flavonoid content of the margarines. Samples were spreadable and palatable

关键词： Food Waste Avocado Peels Extraction Oil Biological Activity Margarine chitosan

ZnO Incorporated Acrylamide Grafted chitosan Based Composite Film for Advanced Wound Healing Applications

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Open Journal of Applied Sciences 2024年第4期14卷 1034-1051页

作者： Khodeja Afrin Kaniz Fatema Fariha Afrose Md. Abdus Samad Azad Md. Shamim Akter Md. Saiful Alam Papia Haque Yeasmin Akter Newaz Mohammed Bahadur Department of Applied Chemistry and Chemical Engineering Noakhali Science and Technology University Noakhali Bangladesh Department of Applied Chemistry and Chemical Engineering University of Dhaka Dhaka Bangladesh

This study was carried out to prepare ZnO nanoparticles incorporated acrylamide grafted chitosan composite film for possible biomedical application especially drug loading in wound healing. ZnO nanoparticles were prepared by co-precipitation method from zinc acetate di-hydrate and incorporated in acrylamide grafted chitosan. FT-IR and TGA of the prepared composite film confirmed the successful incorporation of ZnO nanoparticles in the acrylamide-grafted polymer matrix. SEM images showed that the ZnO nanoparticles were homogeneously distributed on the porous matrix of the composite film. Water uptake and buffer uptake analysis revealed that the composite film could hold water and buffer sufficiently, which facilitated the absorption of exudate from the wound site. Amoxicillin was loaded in the prepared composite film and the maximum loading efficiency was found to be 67.33% with drug concentration of 300 ppm. In vitro studies showed greater antimicrobial activity of drug-loaded composite film compared to both pure film and standard antibiotic disc. Finally, the In vivo mouse model showed maximum healing efficiency compared to conventional gauge bandages because the loading of antibiotic in the film produced a synergistic effect and healing time was reduced.

关键词： chitosan ZnO Nanoparticles Wound Management Acrylamide Grafting Bacterial Resistance Drug Loading

具有可生物降解、细胞相容、抗菌及生物膜控制的壳聚糖磺基甜菜碱衍生物薄膜生物材料的研究

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Engineering 2024年第4期35卷 95-103页

作者： Maoli Yin Yingfeng Wang Xuehong Ren Tung-Shi Huang School of Textile and Garment Anhui Polytechnic UniversityWuhu 241000China State Key Laboratory of New Textile Materials and Advanced Processing Technologies&Key Laboratory of Textile Fiber and Products Ministry of Education&Hubei International Scientific and Technological Cooperation Base of Intelligent Textile Materials and ApplicationSchool of Textile Science and EngineeringWuhan Textile UniversityWuhan 430200China Department of Poultry Science Auburn UniversityAuburnAL 36849USA

The purpose of this research was to develop a chitosan sulfobetaine(CS-SNCC)film via the solutioncasting method as a biodegradable antibacterial material for biomedical applications.chitosan and monochloro-triazine sulfobetaine were used as the raw materials for CS-SNCC preparation,and Fourier-transform infrared(FTIR),ultraviolet–visible(UV-Vis),energy-dispersive X-ray(EDX),and Xray photoelectron spectroscopy(XPS)spectra were used to characterize and analyze the structure of the synthesized CS-SNCC.Furthermore,the swelling property,thermal stability,biodegradability,cytocompatibility,and antibacterial properties of the CS-SNCC film were comprehensively investigated and compared with those of the chitosan film.The results for the film’s enzymatic biodegradation behavior show that the CS-SNCC film undergoes a weight loss of 45.54%after 21 days of incubation.In addition,the CS-SNCC film effectively resists bacterial adhesion,prevents the formation of bacteria biofilms,and exhibits high antibacterial activity,with inactivation rates of 93.43%for Escherichia coli and 91.00%for Staphylococcus aureus.Moreover,the CS-SNCC film shows good cellular activity and cytocompatibility according to the cytotoxicity results.Therefore,the prepared biodegradable,cytocompatible,antibacterial,and biofilm-controlling CS-SNCC film has potential for biomedical applications.

关键词： chitosan Sulfobetaine Antibacterial Biofilm-controlling Film

一种双层多糖水凝胶用于增强益生菌肠道靶向口服递送

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Engineering 2024年第3期34卷 187-194页

作者： Wen-Can Huang Wenjie Wang Wei Wang Yanan Hao Changhu Xue Xiangzhao Mao State Key Laboratory of Marine Food Processing and Safety Control College of Food Science and EngineeringOcean University of ChinaQingdao 266404China. Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China Qingdao Key Laboratory of Food Biotechnology Qingdao 266404China Key Laboratory of Biological Processing of Aquatic Products China National Light IndustryQingdao 266404China

Transplantation of probiotics to the intestine can positively regulate the gut microbiota,thereby promoting the immune system and treating various diseases.However,the harsh gastrointestinal environment and short retention time in the gastrointestinal tract significantly limit the bioavailability and intestinal colonization of probiotics.Herein,we present a double-layer polysaccharide hydrogel(DPH)in the form of a double-layer structure composed of a carboxymethyl cellulose(CMCL)supramolecular inner layer and a dialdehyde alginate(DAA)cross-linked carboxymethyl chitosan(CMCS)outer layer.This doublelayer structure allows DPH to encapsulate and deliver probiotics in a targeted manner within the body.In the stomach,the cage structure of the DPH is closed,and the outer layer absorbs surrounding liquids to form a barrier to protect the probiotics from gastric fluids.In the intestine,the cage structure opens and disintegrates,releasing the probiotics.Thus,DPH endows probiotics with excellent intestine-targeted delivery,improved oral bioavailability,enhanced gastrointestinal tract tolerance,and robust mucoadhesion capacity.The encapsulated probiotics exhibit almost unchanged bioactivity in the gastrointestinal tract before release,as well as improved oral delivery.In particular,probiotics encapsulated by DPH exhibit 100.1 times higher bioavailability and 10.6 times higher mucoadhesion than free probiotics in an animal model 48 h post-treatment.In addition,with a remarkable ability to survive and be retained in the intestine,probiotics encapsulated by DPH show excellent in vitro and in vivo competition with pathogens.Notably,DAA-mediated dynamic crosslinking not only maintains the overall integrity of the hydrogels but also controls the release timing of the probiotics.Thus,it is expected that encapsulated substances(probiotics,proteins,etc.)can be delivered to specific sites of the intestinal tract by means of DPH,by controlling the dynamic covalent crosslinking.

关键词： Polysaccharides chitosan Hydrogels Oral delivery Intestine-targeted

Polysaccharide based supramolecular injectable hydrogels for in situ treatment of bladder cancer

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Chinese Chemical Letters 2024年第1期35卷 259-263页

作者： Chang Zhang Jie Niu Jianqiu Li Hui Zhang Qilin Yu Yong Chen Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic ChemistryNankai UniversityTianjin 300071China College of Life Sciences Key Laboratory of Molecular Microbiology and TechnologyNankai UniversityTianjin 300071China

Implantable system maximizes drug concentration and continuously releases drugs near the tumor,which is an effective tool to solve the difficult retention of chemotherapy drugs in bladder cancer.In this work,a novel polysaccharide supramolecular injectable hydrogel(CCA hydrogels for short)is rapidly constructed by simply mixing cationic chitosan,anionic sulfobutyl etherβ-cyclodextrin(SBE-β-CD)and a trace amount of silver ions.The injected hydrogel reconstituted and regained its shape in less than 1 h,and it can still maintain the elasticity suitable for the human body.By packaging the drug directly,the gel achieves a high concentration of doxorubicin,an anticancer drug.Using MB49-luc cells as the model of bladder tumor for anti-tumor in vivo,the CCA-DOX gel has obvious inhibitory effect on bladder tumor,and its inhibitory effect is much greater than that of free DOX.Therefore,this self-healing injectable hydrogel has great potential for in situ treatment of bladder cancer.

关键词： Sulfobutylether-β-cyclodextrin Supramolecular chemistry chitosan Injectable hydrogel Bladder cancer Local chemotherapy