Surface Modification of Gelatin Nanoparticles with Polyethylenimine as Gene Vector

Wei-Ti Kuo,Meng-Chao Wu,Hong-Yi Huang,Yi-You Huang,Min-Ju Chou

doi:10.1155/2011/646538

Abstract

A novel carrier on balancing the transfection efficiency and minimizing cytotoxicity was designed. Gelatin cross-linked with 1.8 kDa of PEI (GA-PEI 1.8 k) formed stable complex and resulted in high positiveζpotential (42.47 mV) and buffering effect. These nanoparticles with N/P ratio of 30 give high transfection efficiency RLU/μg protein and cell viability (86.4%). These modified GA-PEI nanoparticles, with high transfection efficiency and low cell toxicity, can be a potential gene vector in gene therapy.

Highlights

Gene therapy has been considered as an attractive approach for correcting deficient genes and modulating gene expression [1]
Polyethylenimine (PEI) has high positive charge provided by the nitrogen atoms and shown high affinity to DNA through the electrostatic interaction between the amino group of PEI and phosphate groups of the DNA [20]
We used lowmolecular-weight PEI conjugated onto the surface of gelatin nanoparticles to provide a balance between enhancing transfection efficiency and minimizing cytotoxicity

Summary

Introduction

Gene therapy has been considered as an attractive approach for correcting deficient genes and modulating gene expression [1]. A number of cationic polymers have been investigated as gene carriers, such as synthetic amino acid polymer, polylysine; cationic dendrimers, and pol-yethylenimine (PEI), and carbohydrate-based polymer such as chitosan Among these cationic polymers, PEI has high pH-buffering capacity as a “proton sponge” due to its specific feature. Gelatin is a natural biodegradable polymer, derived from the hydrolysis of collagen, and mainly composed of Journal of Nanomaterials hydroxyproline, proline, and glycine [15] It is considered “generally regarded as safe (GRAS)” material by FDA and has been commonly used in pharmaceuticals, cosmetics, and food products manufacturing [16]. Based on PEI with high pHbuffering capacity and high transfection efficiency, parts of amines on PEI can be conjugated with the carboxylate group of gelatin by EDC to enhance the ζ-potential of nanoparticles and buffering effect. The cell cytotoxicity and transfection efficiency of GE-PEI nanoparticles were assayed in vitro and in vivo

Experimental Details

Results and Discussion

Conclusion