Fig. 6. Increased corneal retention and sustained release of drugs by combining in situ gels and NPs.
(A) Dynamic gamma scintigraphy study showing percentage radioactivity remaining on cornea with time (blue-diamond shape) marketed, (green triangle shape) chitosan in situ gel, (red-square shape) nanosuspension, (purple-circle shape) nanoparticle laden in situ gel (From [134]). (B) Concentration of ketarolac in aqueous humor of rabbit eyes with time from the nanodispersion (E2) and in situ gel incorporated with E2 (NG2) compared to Acular® eye drops (From [137]). (C) The difference of IOP between two eyes (i.e. IOP lowering effect) for (a) linear PNIPAAm eye drops; and (b) linear PNIPAAm and nanoparticles mixture eye drops (From [23]).