PLGA-PEG-Maleimide from PolySciTech used in development of macular degeneration treatment

One of the causes of ocular damage which can lead to blindness is choroidal neovascularization, effectively the over-growth of new blood vessels in the back of the eye. This condition is involved in the development of age-related macular degeneration which can lead to blindness. Recently, researchers at Yantai University (China) utilized Mal-PEG-PLGA (PolyVivo AI020) from PolySciTech (www.polyscitech.com) to develop RGD and TAT peptide modified nanoparticles to deliver therapeutics to ocular tissues as part of treatment of macular degeneration. This research holds promise to provide treatment for a disease which causes blindness. Read more: Chu, Yongchao, Ning Chen, Huajun Yu, Hongjie Mu, Bin He, Hongchen Hua, Aiping Wang, and Kaoxiang Sun. “Topical ocular delivery to laser-induced choroidal neovascularization by dual internalizing RGD and TAT peptide-modified nanoparticles.” International Journal of Nanomedicine 12 (2017): 1353. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5325139/

“Abstract: A nanoparticle (NP) was developed to target choroidal neovascularization (CNV) via topical ocular administration. The NPs were prepared through conjugation of internalizing arginine-glycine-aspartic acid RGD (iRGD; Ac-CCRGDKGPDC) and transactivated transcription (TAT) (RKKRRQRRRC) peptide to polymerized ethylene glycol and lactic-co-glycolic acid. The iRGD sequence can specifically bind with integrin αvβ3, while TAT facilitates penetration through the ocular barrier. 1H nuclear magnetic resonance and high-performance liquid chromatography demonstrated that up to 80% of iRGD and TAT were conjugated to poly(ethylene glycol)– poly(lactic-co-glycolic acid). The resulting particle size was 67.0±1.7 nm, and the zeta potential of the particles was −6.63±0.43 mV. The corneal permeation of iRGD and TAT NPs increased by 5.50- and 4.56-fold compared to that of bare and iRGD-modified NPs, respectively. Cellular uptake showed that the red fluorescence intensity of iRGD and TAT NPs was highest among primary NPs and iRGD- or TAT-modified NPs. CNV was fully formed 14 days after photocoagulation in Brown Norway (BN) rats as shown by optical coherence tomography and fundus fluorescein angiography analyses. Choroidal flat mounts in BN rats showed that the red fluorescence intensity of NPs followed the order of iRGD and TAT NPs > TAT-modified NPs > iRGD-modified NPs > primary NPs. iRGD and TAT dual-modified NPs thus displayed significant targeting and penetration ability both in vitro and in vivo, indicating that it is a promising drug delivery system for managing CNV via topical ocular administration. Keywords: nanoparticles, ocular drug delivery, choroidal neovascularization, RGD, cell-penetrating peptides. Method for iRGD Conjugation: Briefly, Mal–PEG–PLGA was dissolved in acetone and the organic solvent then evaporated, dispersing the solute evenly on the flask wall. The flask was replenished with 0.01 M phosphate-buffered saline (PBS, pH 7.4) and left overnight to react with iRGD. The iRGD was conjugated to Mal–PEG–PLGA (at 4°C, at a 1:1 molar ratio of peptide to Mal–PEG–PLGA).”

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