Physicochemical features and transfection properties of chitosan/poloxamer 188/poly(D,L-lactide-co-glycolide) nanoplexes

Abstract

Donato Cosco,1,5,* Cinzia Federico,1,2,* Jessica Maiuolo,1 Stefania Bulotta,1 Roberto Molinaro,1,3 Donatella Paolino,1,5 Pierfrancesco Tassone,2,4 Massimo Fresta1Department of Health Sciences, 2Department of Experimental and Clinical Medicine, University Magna Græcia of Catanzaro, Catanzaro, Italy; 3Department of NanoMedicine, The Methodist Research Institute, Houston, TX, USA; 4Medical Oncology, Tommaso Campanella Cancer Center, Viale S Venuta, Germaneto, 5Interregional Research Center for Food Safety and Health, University of Catanzaro “Magna Græcia”, Catanzaro, Italy*These authors contributed equally to this paperAbstract: The aim of this study was the evaluation of the effects of two emulsifiers on the physicochemical and technological properties of low molecular weight chitosan/poly (D,L-lactide-co-glycolide) (PLGA) nanoplexes and their transfection efficiency. Nanospheres were prepared using the nanoprecipitation method of the preformed polymer. The mean diameter and surface charge of the nanospheres were investigated by photocorrelation spectroscopy. The degree of binding of the plasmid with the nanoplexes was qualitatively and quantitatively determined. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) testing was performed using HeLa, RPMI8226, and SKMM1 cell lines. Flow cytometry and confocal laser scanning microscopy were used to determine the degree of cellular transfection and internalization of the nanoplexes into cells, respectively. The nanoplexes had a positive zeta potential, and low amounts of PLGA and poloxamer 188 showed a mean colloidal size of ~200 nm with a polydispersity index of ~0.14. The nanoplexes had suitable entrapment efficiency (80%). In vitro experiments showed that the colloidal nanodevices did not induce significant cytotoxicity. The nanoplexes investigated in this study could represent efficient and useful nonviral devices for gene delivery. Use of low amounts of PLGA and poloxamer 188 enabled development of a nanosphere able to transfect cells efficiently. These nanosystems are a helpful platform for delivery of genetic material while preserving therapeutic efficacy.Keywords: nanoplexes, gene delivery, chitosan, poly(D,L-lactide-co-glycolide), poloxamer 188