Microparticles were prepared by an electrospray ionization method.[30 (link), 55 (link)] In general, 60 mg of AcDex or the non-bioresponsive control polymer poly(lactic-co-glycolic acid); PLGA, 6 mg of Lutrol F127 (10 % wt/wt), and with or without 6 mg (10 % wt/wt) of dexamethasone palmitate (DXM; Toronto Research Chemicals, Toronto, Canada) were dissolved in either 400 μL of 4:1 de-acidified CHCl3 (EMD Millipore, Billerica MA, USA):DMSO, or acetonitrile (PLGA). The solutions were briefly sonicated to dissolve all constituents and loaded into a 4 mm diameter tube to prepare for electrospray. A voltage of 14 kV was applied with a flow rate of 0.24 mL/hr and sprayed out of a 31 gauge needle for 1.5 on to glass microscope slides (Thermo-Fisher Scientific). Microparticles were then collected by submerging the slides in 50 mL of 0.02 % Tween 80/PBS (pH 7.4) as an optimal medium to allow for passive diffusion of the hydrophobic DXM. Slides were sonicated briefly to remove the particles, and weighed before and after washing to calculate the amount of particles. The particle suspension was centrifuged at 4500 RPM for 15 min, and resuspended in Tween/PBS solution at 1 mg/mL and hydrated for 20–24 hours at 37°C on a an incubator-shaker at 60 RPM (New Brunswick Scientific). Particles were then again spun and resuspended in appropriate media for the following application.