Thermoresponsive Microcarrier Synthesis

Example 1

A general synthetic method using a free radical polymerization within a water-in-oil (w/o) microemulsion system was developed for the synthesis of thermoresponsive microcarriers (FIG. 2). In this process, the feed solution contained the monomer of the thermoresponsive component N-isopropylacrylamide (IPAAm) and monomers with functional groups that could promote cell attachment or permit further functionalization: methacrylic acid (MA), (3-acrylamidopropyl)trimethylammonium chloride (APTACI), N-[3-(dimethylamino)propyl]methacrylamide (DMAPM) or 2-aminoethyl methacrylate hydrochloride (AMHCI). The monomers were polymerized with the crosslinker N,N′-methylenebis(acrylamide) (MBA) in a water/toluene microemulsion system. Free radical polymerization was initiated at room temperature with ammonium persulfate/N,N,N′,N′-tetramethylethylenediamine or at higher temperatures with the azo initiator 2,2′-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride. Microcarriers produced in this way were sieved, and the fraction in the size range of 125-177 μm was used.