27 - Development of the thermoresponsive magnetic nanoparticle and its deployment in the biotechnology field

Abstract

Various thermoresponsive magnetic nanoparticles, where magnetic nanopolymers are coated with thermoresponsive polymers, are presented in which the coagulation and distribution conditions vary according to the changes in stimuli through the hydration–dehydration of polymers or varied interaction between polymers due to the temperature change. The preparation of magnetic nanoparticles, whose coagulation and dispersion can be controlled by heat, is also possible by coating magnetic nanoparticles with recently developed polymer materials, showing a variety of LCST and UCST. Thermoresponsive magnetic nanoparticles having UCST in water are prepared by immobilizing the NAGAm/MBPDA copolymer on magnetite nanoparticles coated with dextran with a molecular weight of several thousands. The thermoresponsive magnetic nanoparticles do not settle spontaneously at room temperature and cannot be separated magnetically, although when placed in an ice bath, they instantly coagulate and can be easily separated magnetically. The magnetic nanoparticle coupled with antibodies as a diagnosis agent and an antigen detection method via a sandwich method using the antibody-coupled magnetic nanoparticles is also shown. Therma-Max has a very large surface area, low nonspecific adsorption, and has the capability to conduct rapid separation and shows significant potential for various analyses. The thermoresponsive magnetic nanoparticles in transcriptome analysis are also effective in isolating sparsely developed and unstable molecules such as mRNAs, and a rapid analysis of mRNA using Therma-Max is also conducted. The effectiveness of the application of magnetic nanoparticles to the medical field, such as their use as contrast agents in MRI scans and in cancer hyperthermia, has been proved and further development is highly anticipated.