Synthetic and nature-derived lipid nanoparticles for neural regeneration

Challenges and opportunities in nerve regeneration： The central nervous system （CNS） has a limited ability to regen- erate. Subsequent to spinal injury, glial scar formation, creat- ed by fibroblasts, neuroglia, monocytes, and endothelial cells, inhibits regeneration of the injured nerve. The peripheral nervous system （PNS） has a greater regeneration potential than the CNS; however, the current gold standard of treat- ment for a large nerve defect is still autologous nerve grafts, which require multiple surgeries. For this reason, researchers have been trying to regenerate nervous tissues, including brain, spinal cord. and PeriPheral nerves, for decades.

Engineered polymer nanoparticles incorporating L-amino acid groups as affinity reagents for fibrinogen

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 monomers: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,g-globulin,and human serum albumin(HSA)respectively,the NPs that incorporated Nacryloyl-Arg monomers(AArg@NPs)showed the strongest and most specific binding affinity to fibrinogen,when compared with g-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.

pH Readout enhanced ELISA for point-of-care testing of cardiac troponin I

Enzyme-linked immunosorbent assay（ELISA） as a conventional method for protein quantification has its characteristic properties,however,it is challenging to implement excellent portability and sensitivity at the same time.In this study,we described a pH ELISA using synthetic melanin nanoparticles（SMNPs） for the co-immobilization of glucose oxidase（GOx） and second antibody（Ab_2） as signal labels,portable pH meter as signal readout device for point-of-care testing（POCT） of cardiac troponin I（cTnI）.In accordance with the varying amount of cTnI,following sandwich type immunoassay,proportional SMNPs-GOx-Ab_2 were immobilized specifically resulting in corresponding decrease of pH values owing to GOx loaded on SMNPs can high-efficiency convert glucose into gluconic acid.This assay is easy-to-use,portable,sensitive and able to realize POCT,affording a linear range from 0.5 pg/m L to 10 ng/m L and low limit of detection（LOD） of 0.15 pg/m L towards cTnI,which was demonstrated the significant promising in the early diagnosis and screening of acute myocardial infarction.