Synthesis Of MPEG-S-S-Cys-CLB Drug Carrier Compound

At present, research and development of anti-cancer drugs have small molecular weight, poor aqueous solubility phase, diffusion uneven distribution in vivo, causing toxic on normal tissues and organs easily, affecting the quality of life of cancer patients seriously. In recent decades, it was widely used in nanomedicine drug delivery, controlled release, etc., wherein the amphiphilic polymer micelles to improve the solubility of the drug molecules in the aqueous phase, to extend the residence time of the drug in the body, reducing the body resistant resistance.In recent years, researchers have been prepared the stimuli-responsive micelles and carried hydrophobic drug, that could accelerate the rate of release of drug molecules, fewer side effects, enhance biocompatibility. After the micelle surface was modified, optionally with the diseased tissue combined with the targeted drug release, In this paper, prepared by introducing a disulfide bond with oxidation, reduction stimuli-responsive micelles, as the disulfide bond sensitivity to the oxidoreduction environment, it could be destroyed by thiol compound--GSH. Therefore, the design and synthesis of amphiphilic drug compound polymer for clinical treatment and the development of cancer has far-reaching significance.This paper has been selected L-cysteine as centre core molecule, synthesized in phenylacetyl glycine as a hydrophobic segment, disulfide as a crosslinking agent of mPEG(750) composed a hydrophilic segment, anticancer drug molecules-chlorambucil was keyed to it, formed with oxidoreduction stimuli responsive amphiphilic drug compounds. Compound structural characterization and analysis ware prepared by1H NMR, MALDI-TOF-MASS.Polymeric micelles in vitro drug release performance was tested by UV spectrophotometer, releasing an amount of drug molecules was proportional to the concentration of GSH, with the increased of GSH concentration, the release rate s became faster, the cumulative release percentages increased when the concentration of GSH was 1O.OmM, the drug release rate of the drug compound maximum was 82.16%; After released, micelle was cracked, grain diameter became larger and uneven distribution. In addition, the cancer cell toxicity test results was shown that a certain concentrations of compounds could effectively and rapidly inhibit cancer cell growth and enhance water soluble of drug molecules, to improve drug efficacy.The critical micelle concentration of drug compound was determined by pyrene of which as a fluorescent probe, the value was 0.017mg/mL. Particle size of the micelle was 12.91nm, Zeta potential was-13.30mV, poly dispersity index (PDI) was 0.177 that were measured by he dynamic light scattering (DLS); Morphology of polymer micelle was showed multiple cystic irregular spherical and the average particle diameter was about lOnm that were determined via transmission electron microscopy. Micelle polymer lowever critical melting point was 57.2 ℃, which measured by micro melting point determinator. For the treatment of bone cancer, myeloma and other requirements of good solubility and small particle delivery system disease provides potential applications.