Method for preparing Fe3O4 magnetotactic bacterial cellulose spheres

Abstract

The invention relates to a method for preparing Fe3O4 magnetotactic bacterial cellulose spheres. The method comprises the following steps of: preparing nanoscale Fe3O4 (with superparamagnetism) by a coprecipitation method; sterilizing the nanoscale Fe3O4 and a fermentation culture medium respectively and mixing; inoculating gluconacetobacter xylinum (CGMCC No. 2955); controlling the rotate speed of a shaker and culture time to obtain magnetotactic cellulose spheres with different diameters; immersing and washing the magnetotactic cellulose spheres in flowing water for one hour to remove the residual thalli and the culture medium; and washing by using deionized water for five times (the using amount of deionized water every time is 500 milliliters). Due to inconsistent diameters of the magnetotactic bacterial cellulose spheres formed by fermentation, the magnetotactic bacterial cellulose spheres with required diameters can be screened out by using a screen plate with a certain bore diameter, and Fe3O4 particles are distributed uniformly and wrapped in the bacterial cellulose spheres layer by layer along with the biosynthesis and secretion of bacterial cellulose (BC). The magnetotactic bacterial cellulose spheres can be used as a vector of immobilized enzyme or cells, and have the advantage that: after a reaction is finished, the magnetotactic bacterial cellulose spheres are separated by a magnetic field, and can be used repeatedly after the magnetic field is removed.

Description

technical field

[0001] The invention belongs to the field of biotechnology, in particular to a microbial fermentation direct biosynthesis of Fe 3 o 4 Method for magnetic bacterial cellulose spheres. Background technique

[0002] Bacterial cellulose (BC for short) is a polymer compound synthesized by some bacteria. It has an ultra-fine network structure and is a typical nano-biological material. Although bacterial cellulose and cellulose produced by plants or seaweed have the same molecular structure unit, bacterial cellulose has many unique properties such as high crystallinity, high chemical purity, high tensile strength, high elastic modulus, high Water-based, good biocompatibility, and controllability of biosynthesis, etc. These properties are unmatched by fibers from other sources, so they have become the research hotspots of biomaterials in the world in recent years.

[0003] The synthesis methods of BC include static method and dynamic method. In the static method, ...