Fig. 9

Poly (lactic acid)-based intraocular drug delivery systems. A Transmission electron microscopic images of pilocarpine-loaded hollow PLA (HPLA) NPs with tunable shell thickness and intracameral injection of the NPs. B IOP change of the eyes treated with different pilocarpine-loaded HPLA NPs. Follow-up time point: day (d). C The concentration of released pilocarpine (a) and cumulative release percentage (b) of pilocarpine from different types of pilocarpine-loaded HPLA NPs in in vitro drug release assays. Incubation time point: hour (h); day (d). D Histological images of the rabbit eye at day 46 after supraciliary injection of brimonidine-loaded microspheres. Scale bar = 500 μm. E Representative photographs of the rabbit eye 5 min (c) and 1 day (d) after supraciliary injection. Arrows: the injection sites. F The photographs of a microneedle fabricated in this study (compared with a 50 μL drop from a conventional eye dropper). Scale bars = 1 mm. A—C Reprinted from Ref. [81] with permission from Elsevier. D—F Reprinted from Ref. [84] with permission from Elsevier