The Researches Of The Drug-loaded Nanodiamond And Its Effect On HL-60Cell Apoptosis

Detonation nanodiamond (DND) possesses very excellent physical and chemicalproperties, especially, its biocompatibility and surface functional modification. DNDhas very important research value and application prospect in many fields such asbiology and medicine etc. Introducing DND can improve the effect of drug-loading,and apply in the chemotherapy of multi-tumor cells. The further development of DNDfor the variety of the drug-loading and the improvement of the drug effect, prove to bethe important and frontier topic of nanomaterials on biomedicine field in recent years.This dissertation is based on DND, through surface functionalization, conjoined withATRA to investigate the promotion effect in the process of the HL-60cell apoptosis.The main research content and results of the dissertation is as follows:1. The applications of the ultrasound, the high temperature process, through thephase transition and the oxidation reaction and the liquid phase reactions of alcoholmolecules with DND separately to disperse the DND with the particle mean size of5nm. The experiment indicates compared to other methods, the liquid phase reactionmodifiy the ester groups on the DND surface. The DND basicly presents themonodisperse state.2. Combining the ATRA which is applied in the cure of acute promyelocyticleukemia and monodispersed DND with surface modified shell, the hydrophobicity ofmodified groups on the surface of DND particles is to the benefit of the absorptioncombination between the carbon ring terminal of amphoteric ATRA molecule and themodified surface of the DND for the preparation of the DND-ATRA nanocompositesin aqueous solution. Through the transmission electron microscopy (TEM), by themeans of Fourier transform infrared spectrum (FTIR) and UV-Visble fluorescencespectrum detection and so on, to determine the ATRA and DND assembly togethercould be used to improve the effective concentration and availability of ATRA,affecting the apoptosis ratio of HL-60cells. 3. Utilizing the detection methods of the methyl thiazolyl tetrazolium (MTT),fluorescence-activated cell sorting (FACS) and terminal-deoxynucleoitidyltransferase mediated nick end labeling (TUNEL), we systematicly research theapoptosis promotion drug effect of the DND-ATRA nanocomposite for the humanpromyelocytic leukemia cell HL-60cell in vitro. After2days medication, theantitumor activity of HL-60cells is increased by38%, comparing these groupstreated with the solo ATRA, and the efficient apoptosis percentage of HL-60cellreaches up to93%before solo ATRA treated group for8days medication. Bycomparing the regular test results of the growth inhibition of HL-60cells separatelytreated by the solo ATRA and release of the DND-ATRA nanocomposites system toevaluate their antitumor activity, the results show that the complex system doesn’tonly keep the ATRA activity of reversal differentiation of the tumor cells, but alsoeffectively induces the promotion of the differentiation and apoptosis of HL–60cell,and the apoptosis ratio is increased by35%comparing the solo ATRA.. It is provedthat the potiental advantage for the medication. Meanwhile, nanodiamond carrier hasbeen proved to be a good biocompatibility material, inhibiting the chemotherapicejecting effect arised from the membrance transporter protein from the intracellular toextracellular, thus increasing intracellular drug sequestration effects and enhancedpenetration retention (EPR), and revealing nontoxic for the cells. We speculate thatthe intracellular metabolism mode of the nanocomposites is different from the one ofthe solo ATRA, which is the drug directly diffuses, and easily degrades untilcompleted clearance. The nanocomposites reveal the diffusion and accumulationeffect in the intracellular local region, and theATRA continuously induces the HL-60cells into the apoptosis state much longer than the soloATRA.This dissertation has evidenced that the DND-Chemotherapeuticsnanocomposites could provide a potential agentia model for the APL treatment,proving that to establish a new drug delivery system on the basis of nanodiamondshows the very good feasibility and practicability, which provides a certain amount ofthe basis of experiment data and work for the future of the animal model experimentsand the increasing of the loading with a variety of functional groups and drugmolecular for the nanocomposite delivery system, revealing the potential applicationin the clinical field.