Amine endcapped Polyesters are widely applicable for an array of modifications. Materials with a vinyl sulfone or N-hydroxysuccinimide functional unit are highly reactive towards these polyesters allowing for custom endcaps to be placed on the polyester. In the above picture Poly(L-lactic acid) amine endcap (Polyvivo intermediate AI08) was reacted with Flamma Fluor FPI-749 in dichloromethane at room temperature overnight, subsequently purified and then converted into microparticles via a typical homogenization technique (~5-10% polymer in DCM pipetted into 0.5% PVA Mowiol 4-88 with homogenization at 10,000RPMs) and the resultant microparticles are shown in the picture above under brightfield imaging. In this imaging mode the near-IR flourescent dye lends a teal-colored apearance to the microparticles. Under near-IR in-vivo imaging modes this dye has proven itself useful for tracking materials in the skin. Both Flamma Fluor FPI-749 and reactive intermediates can be purchased from the PolySciTech division of Akina, Inc.
