Si-Xue Cheng
Wuhan University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Si-Xue Cheng.
Journal of the American Chemical Society | 2013
Jing Zhang; Zhefan Yuan; Ya Wang; Wei-Hai Chen; Guo-Feng Luo; Si-Xue Cheng; Ren-Xi Zhuo; Xian-Zheng Zhang
A novel type of cellular-uptake-shielding multifunctional envelope-type mesoporous silica nanoparticle (MEMSN) was designed for tumor-triggered targeting drug delivery to cancerous cells. β-Cyclodextrin (β-CD) was anchored on the surface of mesoporous silica nanoparticles via disulfide linking for glutathione-induced intracellular drug release. Then a peptide sequence containing Arg-Gly-Asp (RGD) motif and matrix metalloproteinase (MMP) substrate peptide Pro-Leu-Gly-Val-Arg (PLGVR) was introduced onto the surface of the nanoparticles via host-guest interaction. To protect the targeting ligand and prevent the nanoparticles from being uptaken by normal cells, the nanoparticles were further decorated with poly(aspartic acid) (PASP) to obtain MEMSN. In vitro study demonstrated that MEMSN was shielded against normal cells. After reaching the tumor cells, the targeting property could be switched on by removing the PASP protection layer via hydrolyzation of PLGVR at the MMP-rich tumor cells, which enabled the easy uptake of drug-loaded nanoparticles by tumor cells and subsequent glutathione-induced drug release intracellularly.
Biomacromolecules | 2008
Si Chen; Xian-Zheng Zhang; Si-Xue Cheng; Ren-Xi Zhuo; Zhongwei Gu
Amphiphilic hyperbranched core-shell polymers with folate moieties as the targeting groups were synthesized and characterized. The core of the amphiphilic polymers was hyperbranched aliphatic polyester Boltorn H40. The inner part and the outer shell of the amphiphilic polymers were composed of hydrophobic poly(epsilon-caprolactone) segments and hydrophilic poly(ethylene glycol) (PEG) segments, respectively. To achieve tumor cell targeting property, folic acid was further incorporated to the surface of the amphiphilic polymers via a coupling reaction between the hydroxyl group of the PEG segment and the carboxyl group of folic acid. The polymers were characterized by (1)H NMR, (13)C NMR, and combined size-exclusion chromatography and multiangle laser light scattering analysis. The nanoparticles of the amphiphilic polymers prepared by dialysis method were characterized by transmission electron microscopy and particle size analysis. Two antineoplastic drugs, 5-fluorouracil and paclitaxel, were encapsulated into the nanoparticles. The drug release property and the targeting of the drug-loaded nanoparticles to different cells were evaluated in vitro. The results showed the drug-loaded nanoparticles exhibited enhanced cell inhibition because folate targeting increased the cytotoxicity of drug-loaded nanoparticles against folate receptor expressing tumor cells.
Langmuir | 2008
De-Qun Wu; Tao Wang; Bo Lu; Xiao-Ding Xu; Si-Xue Cheng; Xue-Jun Jiang; Xian-Zheng Zhang; Ren-Xi Zhuo
Supramolecular hydrogels self-assembled by alpha-cyclodextrin and methoxypolyethylene glycol-poly(caprolactone)-(dodecanedioic acid)-poly(caprolactone)-methoxypolyethylene glycol (MPEG-PCL-MPEG) triblock polymers were prepared and characterized in vitro and in vivo. The sustained release of dextran-fluorescein isothiocyanate (FITC) from the hydrogels lasted for more than 1 month, which indicated that the hydrogels were promising for controlled drug delivery. ECV304 cells and marrow mesenchymal stem cells (MSC) were encapsulated and cultured in the hydrogels, during which the morphologies of the cells could be kept. The in vitro cell viability studies and the in vivo histological studies demonstrated that the hydrogels were non-cytotoxic and biocompatible, which indicated that the hydrogels prepared were promising candidates as injectable scaffolds for tissue engineering applications.
Colloids and Surfaces B: Biointerfaces | 2009
Cui-Yun Yu; Bo-Cheng Yin; Wei Zhang; Si-Xue Cheng; Xian-Zheng Zhang; Ren-Xi Zhuo
Composite microparticle drug delivery systems based on chitosan, alginate and pectin with improved pH sensitivity were developed for oral delivery of protein drugs, using bovine serum albumin (BSA) as a model drug. The composite drug-loaded microparticles with a mean particle size less than 200mum were prepared by a convenient shredding method. Since the microparticles were formed by tripolyphosphate cross-linking, electrostatic complexation by alginate and/or pectin, as well as ionotropic gelation with calcium ions, the microparticles exhibited an improved pH-sensitive drug release property. The in vitro drug release behaviors of the microparticles were studied in simulated gastric (pH 1.2 and pH 5.0), intestinal (pH 7.4) and colonic (pH 6.0 and pH 6.8 with enzyme) media. For the composite microparticles with suitable compositions, the releases of BSA at pH 1.2 and pH 5.0 could be effectively sustained, while the releases at pH 7.4, pH 6.8 and pH 6.0 increased significantly, especially in the presence of pectinase. These results clearly suggested that the microparticles had potential for site-specific protein drug delivery through oral administration.
Biomaterials | 2008
Yun-Xia Sun; Xuan Zeng; Qing-Fei Meng; Xian-Zheng Zhang; Si-Xue Cheng; Ren-Xi Zhuo
Arginine-glycine-aspartic acid (RGD) ligand is often chemically attached to polycation vector to improve the transfection efficiency. However, the chemical reaction may reduce or even inactivate the biological activities of peptides. In order to retain the targeting ability and biological activities, the RGD peptide was noncovalently introduced into polycations as gene delivery systems. In this paper, the tripeptide sequence RGD was added to disulfide-containing polyethyleneimine (SS-PEI)/DNA binary complexes to evaluate the influence of RGD addition for the particle size, zeta potential, morphology, and transfection efficiency. GelRed was used as a molecular probe to show the effect of RGD addition on the cellular uptake of complexes. In vitro transfection experiments showed that SS-PEI exhibited comparable transfection efficiency, but lower cytotoxicity in comparison with 25kDa PEI. The transfection efficiency of complexes with RGD in HeLa cells was reduced statistically significantly with the increasing content of RGD peptide, but that in 293T cells was not altered significantly with the increasing content of RGD peptide. The reduced transfection efficiency of SS-PEI/DNA complexes with RGD in HeLa cells was attributed to the targeted binding interactions between the surplus RGD and the alpha(nu)beta(3) and alpha(nu)beta(5) integrins in HeLa cells, which would prevent the binding between RGD in complexes and integrin receptor on the surface of cells as well as nonspecific endocytosis of SS-PEI/DNA complexes mediated by proteoglycan in HeLa cells.
Biomaterials | 2009
De-Qun Wu; Bo Lu; Cong Chang; Chang-Sheng Chen; Tao Wang; Yuan-Yuan Zhang; Si-Xue Cheng; Xue-Jun Jiang; Xian-Zheng Zhang; Ren-Xi Zhuo
Galactosylated and fluorescein isothiocyanate (FITC) labeled polycaprolactone-g-dextran (Gal-PCL-g-Dex-FITC) polymers were synthesized. The grafted polymers can self-assemble into stable micelles in aqueous medium and in serum. Transmission electron microscopy (TEM) images showed that the self-assembled micelles were regularly spherical in shape. Micelle size determined by size analysis was around 120 nm. The anti-inflammation drug prednisone acetate as a model drug was loaded in the polymeric micelles, and the in vitro drug release was investigated. The galactosylated micelles could be selectively recognized by HepG2 cells and subsequently accumulate in HepG2 cells. The in vivo study demonstrated the relative uptake of the micelles by liver is much higher than the other tissues, indicating that the galactosylated micelles have great potential as a liver targeting drug carrier.
Soft Matter | 2008
Xian-Zheng Zhang; Xiao-Ding Xu; Si-Xue Cheng; Ren-Xi Zhuo
Poly(N-isopropylacrylamide) (PNIPAAm) hydrogel is one of the most extensively studied thermosensitive hydrogels, it displays a lower critical solution temperature (LCST) at around 33 °C in aqueous solution and undergoes an abrupt thermoreversible change in volume as the external temperature cycles around this critical temperature. The fast response rate of hydrogels is critically important in some applications, such as artificial organs, actuators, and on-off switches. In this article, we review different strategies, including physical and chemical strategies, for improving the response kinetics of PNIPAAm-based hydrogels. Based on the numerous strategies, the factors that are essential to achieve the fast response rate are identified.
Polymer Chemistry | 2012
Kang Wang; Guo-Feng Luo; Yun Liu; Cao Li; Si-Xue Cheng; Ren-Xi Zhuo; Xian-Zheng Zhang
Novel PEG–polypeptide hybrid drug carriers, poly(ethylene glycol)-b-poly(L-cysteine)-b-poly(L-phenylalanine) (PEG-PCys-PPhe) triblock copolymers, were prepared via the ring-opening polymerization of amino acid N-carboxyanhydrides. The copolymers can self-assemble to form core–shell–corona micelles in aqueous solutions. The shell of the micelles has the ability to self-cross-link (SCL) by the oxidation of thiol groups in the PCys segments. The morphology and stability of SCL micelles were characterized by TEM, DLS and SEM. The results showed the SCL micelles could hold the physical structure of micelles in severe environments. The in vitro drug release in response to GSH was also studied. It was found that the cross-linked shell could be helpful to reduce the drug loss in the extracellular environment. Under a reductive environment, the micelles would undergo the destruction of the cross-linked shell due to the cleavage of disulfide bonds, followed by accelerated drug release from the micelles. The glutathione-responsive SCL micelles could be easily uptaken by HeLa cells, suggesting these micelles might have great potential in intracellular drug delivery.
Biomacromolecules | 2008
Bo Lu; Xiao-Ding Xu; Xian-Zheng Zhang; Si-Xue Cheng; Ren-Xi Zhuo
To develop chitosan-based efficient gene vectors, chitosans with different molecular weights were chemically modified with low molecular weight polyethylenimine. The molecular weight and composition of polyethylenimine grafted N-maleated chitosan (NMC-g-PEI) copolymers were characterized using gel permeation chromatography (GPC) and (1)H NMR, respectively. Agarose gel electrophoresis assay showed that NMC-g-PEI had good binding ability with DNA, and the particle size of the NMC-g-PEI/DNA complexes was 200-400 nm, as determined by a Zeta sizer. The nanosized complexes observed by scanning electron microscopy (SEM) exhibited a compact and spherical morphology. The NMC-g-PEI copolymers showed low cytotoxicity and good transfection activity, comparable to PEI (25 KDa) in both 293T and HeLa cell lines, except for NMC 50K-g-PEI. The results indicated that the molecular weight of NMC-g-PEI has an important effect on cytotoxicity and transfection activity, and low molecular weight NMC-g-PEI has a good potential as efficient nonviral gene vectors.
Colloids and Surfaces B: Biointerfaces | 2008
Bo Wang; Xiao-Ding Xu; Zong-Chun Wang; Si-Xue Cheng; Xian-Zheng Zhang; Ren-Xi Zhuo
In order to investigate the influence of the continuous alkylamide sequence having pH sensitive unit on the temperature sensitivity of poly(N-isopropylacrylamide) (PNIPAAm)-based hydrogel, a monomer, N-(2-(dimethylamino) ethyl)-methacrylamide (DMAEMA), having an ethylamide group as well as an aliphatic tertiary amino group, was designed and synthesized. Hydrogels based on NIPAAm and DMAEMA were prepared via free radical polymerization. The resulted P(NIPAAm-co-DMAEMA) hydrogels were characterized in terms of maximum swelling ratio, swelling kinetics, temperature response kinetics, and effect of pH. The data obtained show that the novel hydrogels have the strong desire to respond to external temperature and pH stimuli. Importantly, because the P(NIPAAm-co-DMAEMA) hydrogels have the continuous alkylamide sequence containing isopropylamide pendant groups from PNIPAAm and ethylamide pendant groups from PDMAEMA, the incorporation of DMAEMA moiety not only provides the pH sensitivity, but also maintains the thermal properties of P(NIPAAm-co-DMAEMA) hydrogels, even as the molar percentage of DMAEMA moiety reaches 14 mol%.