Perspectives of Molecularly Imprinted Polymer-Based Drug Delivery Systems in Ocular Therapy.

Although the human eye is an easily accessible sensory organ, it remains a challenge for drug administration due to the presence of several anatomical and physiological barriers which limit the access of drugs to its internal structures. Molecular imprinting technology may be considered the avant-garde approach in advanced drug delivery applications and, in particular, in ocular therapy. In fact, molecularly imprinted polymers hold the promise to compensate for the current shortcomings of the available arsenal of drug delivery systems intended for ocular therapy. The present manuscript aims to review the recent advances, the current challenges and most importantly to raise awareness on the underexplored potential and future perspectives of molecularly imprinted polymer-based drug delivery systems intended for the treatment of eye diseases.

Topical nanodelivery system of lutein for the prevention of selenite-induced cataract.

Cataracts are responsible for half of the world blindness, surgery being the only viable treatment. Lutein, a naturally occurring carotenoid in the eye, has the potential to reduce cataract progression by protecting the eye from photo-oxidative stress. To restore the eye's natural line of defense against photo-oxidative stress, a formulation was developed using zein and poly(lactic-co-glycolic acid) nanoparticles (NPs) embedded in an optimized bioadhesive thermosensitive gel for the delivery of lutein via topical application. Cataracts were induced in Crl:WI rats via selenite injection at 13 days post-partum, followed by 7 days of treatment with free lutein or lutein-loaded NPs administered orally or topically. Cataract severity was significantly reduced in rats treated with topical applications of lutein-loaded NPs compared to the positive control, while no significant differences were observed in rats treated with other lutein formulations including oral and topically applied free lutein.

Zein Nanoparticles Uptake and Translocation in Hydroponically Grown Sugar Cane Plants.

The main objective of this study was to investigate the uptake and translocation of positively charged zein nanoparticles (ZNPs) in hydroponically grown sugar cane plants. Fluorescent ZNPs (spherical and measuring an average diameter 135 ± 3 nm) were synthesized by emulsion-diffusion method from FITC-tagged zein. Fluorescent measurement following digestion of plant tissue indicated that sugar cane roots had a significant adhesion of ZNPs, 342.5 ± 24.2 µg NPs/mg of dry matter, while sugar cane leaves contained a very limited amount, 12.9 ± 1.2 µg NPs/mg dry matter for high dose(1.75 mg/ml) after 12 h. Confocal microscopy studies confirmed presence of fluorescent ZNPs in the epidermis and endodermis of the root system. Given their ability to adhere to roots for extended periods of time, ZNPs are proposed as effective delivery systems for agrochemicals to sugar cane plants, but more studies are needed to identify effect of nanoparticle exposure to health of the plant.