Application progress in synthetic and natural polymer materials for dural membrane repair / 国际生物医学工程杂志

The dura mater is a double-layer tough membrane tissue located between the surface of the brain and the inner surface of the skull that supports and protects the brain tissue. The phenomenon of dural defects caused by tumor resection, inflammation destruction, and craniotomies is becoming more common clinically. Therefore, the development of effective dural repair materials can not only reduce the leakage of cerebrospinal fluid and the occurrence of epilepsy complications but also promote the recovery of the dural defect to its normal physiological structure. With the continuous development of modern medicine, many biomaterials have been developed for dural defect repair. At present, the most promising and most researched biomaterials are synthetic polymer materials and natural polymer materials. Synthetic polymer materials have been extensively studied by domestic and foreign scholars due to their stable performance, low foreign body infection, and easy mass production advantages. Natural polymer materials are the most promising biomaterials because of their extensive sources, excellent biocompatibility, and biodegradability advantages. This article summarizes the research progress based on synthetic polymer materials and natural polymer materials in dural repair materials. In this review paper, the application progress of synthetic polymer materials and natural polymer materials in dural membrane repair was reviewed.

Engineered polymer nanoparticles incorporating L-amino acid groups as affinity reagents for fibrinogen / 药物分析学报

Synthetic polymer hydrogel nanoparticles(NPs)were developed to function as abiotic affinity reagents for fibrinogen.These NPs were made using both temperature-sensitive N-isopropyl acrylamide(NIPAm)and L-amino acid monomers.Five kinds of L-amino acids were acryloylated to obtain functional mono-mers:L-phenylalanine(Phe)and L-leucine(Leu)with hydrophobic side chains,L-glutamic acid(Glu)with negative charges,and L-lysine(Lys)and L-arginine(Arg)with positive charges.After incubating the NPs with fibrinogen,y-globulin,and human serum albumin(HSA)respectively,the NPs that incorporated N-acryloyl-Arg monomers(AArg@NPs)showed the strongest and most specific binding affinity to fibrin-ogen,when compared with y-globulin and HSA.Additionally,the fibrinogen-AArg binding model had the best docking scores,and this may be due to the interaction of positively charged AArg@NPs and the negatively charged fibrinogen D domain and the hydrophobic interaction between them.The specific adsorption of AArg@NPs to fibrinogen was also confirmed by the immunoprecipitation assay,as the AArg@NPs selectively trapped the fibrinogen from a human plasma protein mixture.AArg@NPs had a strong selectivity for,and specificity to,fibrinogen and may be developed as a potential human fibrinogen-specific affinity reagent.

Research advances in materials for microspheres as drug delivery system / 中国药科大学学报

@#Microsphere as a drug delivery system with broad prospect for development and application has always been a research focus in pharmaceutics for its. Though literature survey of related papers published in domestic and foreign journals by Chinese authors in 2016, the research advances of materials of microspheres, which can be divided into natural polymer materials, synthetic polymer materials and inorganic materials, were summarized. Microsphere products at home and abroad were also analyzed. This review will provide some reference for correlative researchers.

Colonic delivery of film coated meloxicam tablets using natural polysaccharide polymer mixture.

Now days natural polysaccharides are extensively used for the development of solid dosage forms for delivery of drug to the colon. The objective of the present study was to develop a site-specific drug, single unit formulation allowing targeted drug release in the colon. Solid unit dosage forms were prepared using polysaccharides or synthetic polymer included xanthan gum, pectin, chitosan and Eudragit-E. Meloxicam was used as a model drug. The prepared tablets were enteric coated with Eudragit-S 100 to give protection in the stomach. The coated tablets were tested in-vitro for their suitability as colon specific drug delivery systems. The dissolution data so obtained illustrates that enteric coated tablets containing 3% chitosan as a binder, showed only 12.5% drug release in the first 5 h, which is the usual upper gastrointestinal transit time, whereas, tablets prepared using xanthan gum as binder, were unable to protect drug release under similar conditions. Solid formulations containing pectin as a binder formed time-dependent release formulations. 28% drug release was observed in the usual upper gastrointestinal tract conditions, when used in a concentration of 5.92% in the tablets.

Colonic delivery of film coated meloxicam tablets using natural polysaccharide polymer mixture.

Now days natural polysaccharides are extensively used for the development of solid dosage forms for delivery of drug to the colon. The objective of the present study was to develop a site-specific drug, single unit formulation allowing targeted drug release in the colon. Solid unit dosage forms were prepared using polysaccharides or synthetic polymer included xanthan gum, pectin, chitosan and Eudragit-E. Meloxicam was used as a model drug. The prepared tablets were enteric coated with Eudragit-S 100 to give protection in the stomach. The coated tablets were tested in-vitro for their suitability as colon specific drug delivery systems. The dissolution data so obtained illustrates that enteric coated tablets containing 3% chitosan as a binder, showed only 12.5% drug release in the first 5 h, which is the usual upper gastrointestinal transit time, whereas, tablets prepared using xanthan gum as binder, were unable to protect drug release under similar conditions. Solid formulations containing pectin as a binder formed time-dependent release formulations. 28% drug release was observed in the usual upper gastrointestinal tract conditions, when used in a concentration of 5.92% in the tablets.

Cervical Anterior Interbody Fusion with B.O.P(Biocompatible Osteoconductive Polymer)

Anterior interbody fusion has used for instability and anatomical reconstruction in various cervical diseases since 1958 by cloward. Bone grafts such as autograft, allograft, xenograft and synthetic materials were utilized in fusion as a graft material. But conventional fusion materials have problems including postoperative morbidity, transmission of diseases, foreign body reaction, collapse, prolongation of operation time. A new synthetic material, Biocompatible Osteoconductive Polymer(B.O.P) is developed and it was useful for cervical anterior interbody fusion as a substitute for other fusion materials.