Renyun Zhang

The Enhancement Effect of Gold Nanoparticles in Drug Delivery and as Biomarkers of Drug-Resistant Cancer Cells

The enhancement effect of 3‐mercaptopropionic acid capped gold nanoparticles (NPs) in drug delivery and as biomarkers of drug‐resistant cancer cells has been demonstrated through fluorescence microscopy and electrochemical studies. The results of cell viability experiments and confocal fluorescence microscopy studies illustrate that these functionalized Au NPs could play an important role in efficient drug delivery and biomarking of drug‐resistant leukemia K562/ADM cells. This could be explored as a novel strategy to inhibit multidrug resistance in targeted tumor cells and as a sensitive method for the early diagnosis of certain cancers. Our observations also indicate that the interaction between the functionalized Au NPs and biologically active molecules on the surface of leukemia cells may contribute the observed enhancement in cellular drug uptake.

Synergistic enhancement effect of magnetic nanoparticles on anticancer drug accumulation in cancer cells

Three kinds of magnetic nanoparticle, tetraheptylammonium capped nanoparticles of Fe(3)O(4), Fe(2)O(3) and Ni have been synthesized, and the synergistic effect of these nanoparticles on the drug accumulation of the anticancer drug daunorubicin in leukaemia cells has been explored. Our observations indicate that the enhancement effect of Fe(3)O(4) nanoparticles is much stronger than that of Fe(2)O(3) and Ni nanoparticles, suggesting that nanoparticle surface chemistry and size as well as the unique properties of the magnetic nanoparticles themselves may contribute to the synergistic enhanced effect of the drug uptake of targeted cancer cells.

Blends of TiO2 nanoparticles and poly (N-isopropylacrylamide)-co-polystyrene nanofibers as a means to promote the biorecognition of an anticancer drug

The poly (N-isopropylacrylamide)-co-polystyrene (PNIPAM-co-PS) nanofibers have been fabricated by electrospinning, and the blends of PNIPAM-co-PS nanofibers with titanium dioxide (TiO(2)) nanoparticles have been characterized and utilized as the new nanocomposites to enhance the relevant detection sensitivity of biomolecular recognition of an anticancer drug daunorubicin. Our observations demonstrate that upon application of the nanoTiO(2)-PNIPAM-co-PS polymer nanocomposites, the drug molecules could be readily deposited on the surface of the relevant blends so that the remarkable enhancement effect of the new nanocomposites on the respective biorecognition of daunorubicin could be observed, suggesting the potential valuable application of the blending of the nanoTiO(2) and PNIPAM-co-PS polymer nanocomposites in high sensitive bioanalysis.

Synergistic effect of the combination of nanoparticulate Fe3O4 and Au with daunomycin on K562/A02 cells

In this study, we have explored the possibility of the combination of the high reactivity of nano Fe3O4 or Au nanoparticles and daunomycin, one of the most important antitumor drugs in the treatment of acute leukemia clinically, to inhibit MDR of K562/A02 cells. Initially, to determine whether the magnetic nanoparticle Fe3O4 and Au can facilitate the anticancer drug to reverse the resistance of cancer cells, we have explored the cytotoxic effect of daunomycin (DNR) with and without the magnetic nano-Fe3O4 or nano-Au on K562 and K562/A02 cells by MTT assay. Besides, the intracellular DNR concentration and apoptosis of the K562/A02 cells was further investigated by flow cytometry and confocal fluorescence microscopic studies. The MDR1 gene expression of the K562/A02 cells was also studied by RT-PCR method. Our results indicate that 5.0 × 10−7 M nano-Fe3O4 or 2.0 × 10−8 M nano-Au is biocompatible and can apparently raise the intracellular DNR accumulation of the K562/A02 cells and increase the apoptosis of tumor cells. Moreover, our observations illustrate that although these two kinds of nanoparticles themselves could not lower the MDR1 gene expression of the K562/A02 cells, yet they could degrade the MDR1 gene level when combining with anticancer drug DNR. This raises the possibility to combine the nano-Fe3O4 or nano-Au with DNR to reverse the drug resistance of K562/A02 cells, which could offer a new strategy for the promising efficient chemotherapy of the leukemia patients.

The application of poly(N-isopropylacrylamide)-co-polystyrene nanofibers as an additive agent to facilitate the cellular uptake of an anticancer drug.

In this paper, we have fabricated poly(N-isopropylacrylamide)-co-polystyrene (PNIPAM-co-PS) nanofibers by electrospinning and explored the possibility to utilize the PNIPAM-co-PS nanofibers to enhance the permeation and uptake of the anticancer drug daunorubicin in drug-sensitive and drug-resistant leukemia K562 cells. Our MTT assay and electrochemical studies demonstrate that PNIPAM-co-PS nanofibers could play an important role in facilitating the cell track and drug delivery to the cancer cells. Meanwhile, the observations of atomic force microscopy (AFM) and confocal fluorescence microscopy indicate that the relevant interaction of the PNIPAM-co-PS nanofibers with bioactive molecules on the membrane of leukemia cell lines could affect the intracellular drug uptake positively and lead to the efficient accumulation of daunorubicin in drug-sensitive and drug-resistant cancer cells.