Preparation and characterization of oxaliplatin drug delivery vehicle based on PEGylated half-generation PAMAM dendrimer

Dendrimers were well-known as a polymeric nanoparticle drug carrier system. Among them, polyamidoamine (PAMAM) dendrimers were firstly and systematically studied. Herein, to explore the additional modification of PAMAM for drug deliver application, this study assessed the PEGylated half-generation G3.5 to load oxaliplatin (OXA). The proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectroscopy (FTIR) spectroscopy were used to confirm the successful synthesis of G3.5, and PEGylated G3.5. PEG modification on G3.5 neutralized the negative charge of G3.5 that was confirmed by zeta potential measurement, and increased the dimension of G3.5 from 10 to 100 nm that was carried out by TEM technique. G3.5-PEG showed the high drug loading efficiency of 75.69%. The release kinetic of OXA from G3.5-PEG@OXA indicated that no burst released phenomenon occurred (11.95% within first hour) and sustainable release was achieved. In cytotoxicity test with normal cells of L929 fibroblasts, the carrier system of G3.5-PEG did not induced any cytotoxicity. To test the killing effect of G3.5-PEG@OXA on cancerous cells of human cervical cancer cells (HeLa), lung adenocarcinoma (A549), and breast cancer (MCF-7), resazurin test and live/dead staining assay was used to observe the alive cells. The increase of OXA amount in G3.5-PEG@OXA lead to decrease the cell viability from 79.90–56.97% (HeLa), 84.80–64.00% (A549), and 92.00–65.00% (MCF-7) after 48 h treatment.