Synthesis and Characterization of Polymeric Materials

Poly(lactic-co-glycolic acid) (ratio 50:50; M_w 7–17 kDa; alkyl ester terminated), polystyrene (M_w 35 kDa), fluorescein (acid free, 95%), Nile blue chloride (85%), Nile red (technical grade), IR780 (98%), fluorescein diacetate (FDA), dextran (9–11 kDa), acrylamide (molecular biology grade), and N,N′-methylene bis(acrylamide) (99%) were purchased from Sigma-Aldrich. Pluronic F127 (13 kDa) was purchased from O-BASF. Lithium acylphosphinate salt was synthesized according to a procedure published by Fairbanks et al.^{63 (link)} Dextran was acetalated according to a procedure described by Suarez et al.^{64 (link)} The synthesis of polyesters 1 and 2 can be found elsewhere.^{45 (link)} Chloroform (CHCl₃, 99.8%, EMD), dimethylformamide (DMF, 99%, Aldrich), tetrahydrofuran (THF, 99%, Fischer Scientific), and deuterated water (D 99.9%, Cambridge Isotope Inc.) were used without further purification. Deionized water (DI H₂O) was purified from a Millipore system (18.2 MΩ).