Synthesis And Free Radical Activity Of Nano Fullerene Bis-functionalized RGD Peptide

Due to the special structure like cage of fullerene, it has its own unique physical and chemical properties, so that it can be used in biomedical. In particular, there is a very good prospect in antibacterial, antioxidant, drug carrier, etc. Its poor solubility in water hinders the research in the biomedical field, thus we expect to improve the shortcoming via chemical modification. Consequently, fullerene and the targeted RGD peptide are connected. Therefore fullerene bis-addition RGD peptide is synthesized in this paper, aim to improve the solubility of fullerene in water and its properties in biology simultaneously.In this paper, two kinds of fullerene RGD peptide derivatives were synthesized by the combination of solid and liquid phase: fullerene mono RGD peptide derivatives(FP(RGD)), fullerene bis addition RGD peptide derivatives(FbP(RGD)), and the nanoparticle suspension of the above two derivatives were also synthesized by the method of organic solvent exchange. At last, the effect of nanoparticles on superoxide anion was determined by means of pyrogallol oxidation, the effect of nanoparticles on hydroxyl radical via methyl violet-Fenton system. The achievements are as follows:The target product FP(RGD) and FbP(RGD) were synthesized by the combination of solid and liquid phase, their structures were also characterized through MALDI-TOF, FT-IR, UV-Vis and others.FP(RGD) and FbP(RGD) nanoparticles aqueous suspension were successfully prepared by the method of organic solvent exchange. And both of the suspensions were characterizated and detected by the particle size distribution, surface Zeta-potential and the transmission electron microscopy(TEM). The results showed that they had uniform particle size, good dispersion, stable system, and TEM indicated both of them had good morphology.The effect of nanoparticles on superoxide anion radical was determined by means of pyrogallol oxidation. The results showed that four nanoparticle suspensions had good scavenging ability for O2·- in dark conditions. The orders of scavenging ability for superoxygen anion radical were FP(RGD)>FPy, FbP(RGD)>FbPy1, respectively, and the ability of FP(RGD) and FbP(RGD) were far greater than VC of the same concentration.The effect of nanoparticles on hydroxyl radical via methyl violet-Fenton system was determined. The results showed that the four nanoparticle suspensions had good scavenging ability for ·OH in dark conditions. The orders of scavenging ability for ·OH were FP(RGD)>FPy,FbP(RGD)>FbPy1, respectively, and the ability of FP(RGD) and FbP(RGD) were far greater than mannitol of same concentration. The ability of producing hydroxyl radicals of these nanoparticles was revealed under irradiation, and the orders of this ability were FP(RGD)>FPy,FbP(RGD)>FbPy1.In summary, the water solubility of these two fullerene RGD peptide derivatives synthesized in this paper are improved, and the scavenging ability on superoxide anion radical and hydroxyl radical are very strong. The introduction of RGD peptide makes the scavenging ability of the fullerene on free radical has been greatly improved, thus it further illustrates that the fullerene RGD peptide derivatives designed have good application prospects in biomedical.