[Arg-Gly-Asp-containing peptide combining with the biomimetic and modified PLGA-(ASP-PEG)]

Arg-Gly-Asp-(RGD) containing peptide characterized as the non-viral gene vector was synthesized to modify the surface of PLGA-(ASP-PEG). The Peptide (K16-GRGDSPC) was synthesized. PLGA-(ASP-PEG) was executed into chips A, B and C. Chip C was regarded as control. Chips A and B reacted with the cross-linker, then Chip A reacted with peptide. Mass spectrometry (MS) and high performance liquid chromatography (HPLC) detected the molecular weight and the purity of peptide. Sulphur in the surface of materials was detected by X-ray photoelectron spectrometry (XPS). The peptide content in the residual solution was detected by Spectrometer. HPLC showed the peptide purity was 94.13%; MS showed the molecular weight was 2741.26. XPS revealed the binding energy of the sulphur in reacted Chip A was 164 eV in reacted Chip B, 164eV and 162 eV; the ratios of carbon to sulphur in reacted Chip A and B were 99.746:0.1014 and 99.574:0.4255, respectively. There was no sulphur in Chip C. The optical density value (OD) of the resident solution was 0.069. The peptide density of reacted Chip A was 0.04 mg/mm2. The peptide was manufactured and linked to the surface of the biomimetic PLGA-(ASP-PEG) with the cross-linker.