In the present study, nonionic surfactant vesicles (niosomes) formulated with Span 20, cholesterol, and novel synthesized spermine-based cationic lipids with four hydrocarbon tails in a molar ratio of 2.5:2.5:1 were investigated as a gene carrier. The effects of the structure of the cationic lipids, such as differences in the acyl chain length (C14, C16, and C18) of the hydrophobic tails, as well as the weight ratio of niosomes to DNA on transfection efficiency and cell viability were evaluated in a human cervical carcinoma cell line (HeLa cells) using pDNA encoding green fluorescent protein (pEGFP-C2). The niosomes were characterized both in terms of morphology and of size and charge measurement. The formation of complexes between niosomes and DNA was verified with a gel retardation assay. The transfection efficiency of these cationic niosomes was in the following order: spermine-C18 > spermine-C16 > spermine-C14. The highest transfection efficiency was obtained for transfection with spermine-C18 niosomes at a weight ratio of 10. Additionally, no serum effect on transfection efficiency was observed. The results from a cytotoxicity and hemolytic study showed that the cationic niosomes were safe in vitro. In addition, the cationic niosomes showed good physical stability for at least 1 month at 4°C. Therefore, the cationic niosomes offer an excellent prospect as an alternative gene carrier.

These novel cationic niosomes may constitute a good alternative carrier for gene transfection.

Cationic lipid-based nanoparticulate systems are delivery systems that has been widely used in pharmaceutical field including gene delivery. There are many barriers obstructing genetic materials and their delivery systems to reach the target. Serum is one of the imperative factor that should be investigated. Therefore, the aim of this study was to examine the effect of serum on DNA protection ability of spermine-liposomes and niosomes by evaluating the percentage of transfection efficiency in Hela cell and observing the DNA degradation band using agarose gel electrophoresis in the presence of serum. The results showed that the percentage of transfection efficiency of spermine-liposomes was dramatically decreased when serum is presented (p< 0.05). In contrast, whether or not the serum is presented, the spermine-niosomes showed no significant difference in transfection efficiency. Concisely, liposomes could slightly protect DNA from DNase in the serum, whereas, niosomes had potential ability to protect DNA from the enzymes in serum. This result revealed an advantage of the cationic niosomes system as a gene carrier over the cationic liposomes.

The objective of this study was to investigate the transfection efficiency of quaternized chitosan or trimethylated chitosans (TMCs) using the plasmid DNA encoding green fluorescent protein (pEGFP-C2) on human cervical carcinoma cell line (HeLa cells). The factors affecting the transfection efficiency, e.g. degree of quaternization (DQ) and polymer/DNA weight ratio were evaluated. The results revealed that the complexes of TMC30 with DNA had the highest transfection efficiency and safety followed by the complexes of TMC60 and TMC94, respectively. Increasing the DQ of chitosan not only improve the efficiency of gene delivery, but also increase cytotoxicity. In conclusion, TMC30 showed elevated potential as a gene carrier by efficient DNA condensation and mediated the highest level of gene transfection with negligible cytotoxicity in HeLa cells.