Polylactic acid-zinc oxide micro-nano multi-level structure composite microsphere material and its application

Abstract

The invention discloses a polylactic acid-zinc oxide micro-nano multi-level structure composite microsphere material and its application. The polylactic acid-zinc oxide micro-nano multi-level structure composite microsphere material of the present invention is dissolved polylactic acid in methylene chloride , to obtain a polylactic acid solution, using microfluidic technology, drop the polylactic acid solution into a polyvinyl alcohol aqueous solution to obtain polylactic acid microspheres. Immerse the polylactic acid microspheres into the zinc acetate solution. After the surface is covered with zinc acetate, take out the microspheres and treat them with oxygen through an oxygen plasma cleaner to bind the surface of the microspheres to zinc oxide. The polylactic acid microspheres with zinc oxide on the surface are placed in a mixture of zinc nitrate and hexamethylenetetramine, stirred in a constant temperature water bath at 80-100°C, and washed and dried after the reaction is complete. The microsphere has a stable structure, uniform size, a diameter of 50-400 μm, and a zinc oxide nanorod length of 10-50 nm. Seeding human adipose-derived mesenchymal stem cells on the microspheres can promote the proliferation of stem cells and maintain the stemness of stem cells.

Description

technical field [0001] The invention relates to the technical field of biomedical engineering, in particular to a polylactic acid-zinc oxide micro-nano multi-level structure composite microsphere material and its application in maintaining stem cell stemness. Background technique [0002] Stem cell therapy technology has shown great clinical application prospects in gene therapy, autoimmune diseases, brain and nervous system diseases, and cardiovascular diseases. Among them, the advantages of autologous adult stem cell transplantation are particularly prominent. [0003] Adult stem cells refer to undifferentiated cells present in an already differentiated tissue. Under certain conditions, adult stem cells either produce new stem cells, or differentiate according to a certain program to produce various specific cell types. Compared with embryonic stem cells, adult stem cells have many advantages, for example: (1) Since the major histocompatibility complex (MHC) of each indi...

AI Technical Summary

Problems solved by technology

(2) Although embryonic stem cells can differentiate into various cell types, this differentiation is "non-localized". At present, it is not possible to control the differentiation of embryonic stem cells into corresponding cells in specific parts. The current practice can easily lead to teratomas ; and the above-mentioned problems do not exist in the application of adult stem cells

However, due to the characteristics of large specific surface area and large specific surface energy, nano-zinc oxide is easy to agglomerate; on the other hand, the surface of nano-zinc oxide is very polar, and it is not easy to disperse uniformly in organic media, which greatly limits its nano-scale performance. effect play

At present, there is no form of microspheres made of polylactic acid and zinc oxide.

[0006] In addition, microspheres are currently mainly used in the fields of drug sustained release, cell scaffolding, and cell injection. There are no reports on the use of microspheres to promote the proliferation of adult stem cells and maintain the stemness of adult stem cells.

Images