Preparation Of Multifunctional Nano Drug Carrier And Molecular Fluorescent Probe And Its Application In Biochemical Analysis

With the continuous improvement of living standards,the amount of diseases caused by environmental pollution and irrational diets increase gradually.Meanwhile,cancer has become the main reason of the rising rates of human mortality.The introduction of novel nanomaterials provides an effective way for the delivery of anticancer drugs and targeted therapy.At the same time,the detection of carcinogens has become a hot spot in the field of contemporary biomedicine.1.Nano drug delivery system has important significance for monitoring apoptosis process and cell imaging exactly in tumor diagnostic and therapeutic field.Herein,we designed CS-AuNPs-DOX nanocomplex for target drug delivery and fluorescence-enhanced cell imaging.For cancer therapy,doxorubicin(DOX)was connected with CS-AuNPs by disulfide linkages which could be divided by glutathione(GSH)in cancer cells especially.Moreover,red emissive DOX was quenched readily by special quenching way of Fluorescence Resonance Energy Transfer(FRET)from DOX to CS-AuNPs,rendering monitoring target drug release by visual fluorescence signals.The released drug served as a signal indicator for cancer cells with red fluorescence and was further applied for stimuli-responsive drug treatment.After a comprehensive research of detection for GSH,pro-apoptosis for cancer cells and suppression for tumor tissues in vivo,the CS-AuNPs-DOX nanocomposite showed enhanced property clearly.This proposal supplies an excellent strategy for drug delivery and cell imaging,which acts as a hopeful candidate for anticancer therapeutic applications.2.We designed a miRNA-responsive nanocomposite probe based on photothermal therapy and chemotherapy.First,The gold nanorods with photothermal properties were synthesized as nano drug carriers.The surface of gold nanorods were then modified with DNA to accomplish the drug loading.Finally,the nanocomposite could target tumor by introducing folic acid,and target drug therapy was also achieved.The miRNA competed with double-stranded DNA to release doxorubicin and the fluorescence signal of DOX was restored obviously.This nanobiosensor could not only detect miRNA in tumor cells,but also possess dual-function of diagnosis and treatment of cancer.This proposal provides an excellent strategy for detection,cell imaging,and treatment,which serves as a promising candidate for biomedical research.3.An original background-free sensing pattern for hydrazine was developed by making use of a green fluorescent chromophore generated in situ from the reaction of the probe and analytes in CTAB micelles as an indicator.The ultra-sensitive detection scheme showed a relatively low detection limit of 0.42 nM.In addition,the biosensor had excellent performances in terms of sensitivity,anti-interference ability,and imaging stability,and could be further used in the study of biological experiments in vivo.