Oskuee Reza Kazemi, Dosti Fatemeh, Gholami Leila, Malaekeh-Nikouei Bizhan
Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
Mater Sci Eng C Mater Biol Appl. 2015 Apr;49:290-296. doi: 10.1016/j.msec.2015.01.016. Epub 2015 Jan 7.
Nowadays gene delivery is a topic in many research studies. Non-viral vectors have many advantages over viral vectors in terms of safety, immunogenicity and gene carrying capacity but they suffer from low transfection efficiency and high toxicity. In this study, polyallylamine (PAA), the cationic polymer, has been modified with hydrophobic branches to increase the transfection efficiency of the polymer. Polyallylamine with molecular weights of 15 and 65kDa was selected and grafted with butyl, hexyl and decyl acrylate at percentages of 10, 30 and 50. The ability of the modified polymer to condense DNA was examined by ethidium bromide test. The complex of modified polymer and DNA (polyplex) was characterized for size, zeta potential, transfection efficiency and cytotoxicity in Neuro2A cell lines. The results of ethidium bromide test showed that grafting of PAA decreased its ability for DNA condensation but vectors could still condense DNA at moderate and high carrier to DNA ratios. Most of polyplexes had particle size between 150 and 250nm. The prepared vectors mainly showed positive zeta potential but carriers composed of PAA with high percentage of grafting had negative zeta potential. The best transfection activity was observed in vectors with hexyl acrylate chain. Grafting of polymer reduced its cytotoxicity especially at percentages of 30 and 50. The vectors based of PAA 15kDa had better transfection efficiency than the vectors made of PAA 65kDa. In conclusion, results of the present study indicated that grafting PAA 15kDa with high percentages of hexyl acrylate can help to prepare vectors with better transfection efficiency and less cytotoxicity.
如今，基因递送是许多研究中的一个热门话题。在安全性、免疫原性和基因携带能力方面，非病毒载体相对于病毒载体具有许多优势，但它们存在转染效率低和毒性高的问题。在本研究中，阳离子聚合物聚烯丙胺（PAA）已用疏水支链进行修饰，以提高该聚合物的转染效率。选择了分子量为15kDa和65kDa的聚烯丙胺，并分别以10%、30%和50%的比例与丙烯酸丁酯、丙烯酸己酯和丙烯酸癸酯进行接枝。通过溴化乙锭试验检测修饰后聚合物凝聚DNA的能力。对修饰后的聚合物与DNA的复合物（多聚体）进行了粒径、zeta电位、转染效率和在Neuro2A细胞系中的细胞毒性表征。溴化乙锭试验结果表明，PAA接枝后其凝聚DNA的能力下降，但载体在中等和高载体与DNA比例下仍能凝聚DNA。大多数多聚体的粒径在150至250nm之间。制备的载体主要显示正zeta电位，但接枝百分比高的PAA组成的载体具有负zeta电位。在含丙烯酸己酯链的载体中观察到最佳转染活性。聚合物接枝降低了其细胞毒性，尤其是在30%和50%的比例时。基于15kDa PAA的载体比基于65kDa PAA的载体具有更好的转染效率。总之，本研究结果表明，用高百分比的丙烯酸己酯接枝15kDa的PAA有助于制备具有更好转染效率和更低细胞毒性的载体。
