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A new derivative of ordered mesoporous carbon (GSH-CMK-3) has been prepared by chemical modification and functionalization of ordered mesoporous carbon with glutathione. The composite was fully characterized by means of Fourier transforming infrared spectroscopy (FT-IR), scanning electron microscope (SEM) image and thermogravimetric analysis (TGA). GSH-CMK-3 showed favorable chemical stability, thermal stability and excellent adsorption performance toward Cd2+and a maximum adsorption capacity of 87.87 mg/g was achieved. The adsorption kinetic follows pseudo-second-order adsorption model. In a sequential injection mini-column separation system, 0. 006 mol/L sulfourea (in 0. 2 mol/L HNO3) was adopted as eluent and the elution efficiency was 96%. With a sample volume of 1000 μL and 50 μL of eluate, an enrichment factor of 17.3 was obtained. A procedure for on-line selective separation and preconcentration of trace Cd2+was developed by graphite furnace atomic absorption spectrometry. Along with a detection limit of 1.9 ng/L (n=7,3σ) and a linear range of 0.05-0.20 μg/L, a RSD of 2.9% (n=13,100 ng/L) was achieved. The method was validated by analyzing Cd2+in a certified reference material GBW08608.
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OBJECTIVE:To establish the mesoporous carbon nano-drug delivery system (MCNs) with chemotherapy drugs loaded and holding photothermal and photodynamic combined effect,and study its anti-multidrug-resistant tumor effect in vitro. METHODS:MCNs was prepared by low-concentration hydrothermal route,and the MCNs surface was carboxylated by the mixed acid ultrasound method to made MCNs-COOH (MCNC). The morphology and surface properties were evaluated. Adriamycinc (ADR)was loaded into MCNC to fabricate ADR/MCNC via adsorption method. Drug loading capacity was calculated by UV,and drug release profile was investigated by dialysis method. ADR-resistant human breast cancer MCF-7/ADR cells were chosen,and cell uptake and positioning of ADR/MCNC were observed by confocal laser microscopy;cytotoxicity of ADR/MCNC was detected by MTT method;and intracellular reactive oxygen species(ROS)level under NIR irradiation was measured by flow cytometry. RE-SULTS:The particle size of prepared MCNs was about 90 nm,with carboxyl in surface. The specific surface area was 541.62 m2/g,pore volume was 0.34 cm3/g,and pore size distribution was 2.5 nm,with significant photothermal effect. The drug loading ca-pacity of ADR/MCNC was 47.4%,showing pH/NIR responsiveness release characteristics. It can promote ADR in cell uptake and nuclear accumulation and induce MCF-7/ADR cell to generate ROS under NIR irradiation,with significant inhibitory effect. CON-CLUSIONS:MCNs is prepared successfully,and ADR/MCNC has an effect on anti-multidrug-resistant tumors.
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OBJECTIVE: To improve the dissolution rate of fenofibrate (FNB) by using starch source mesoporous carbon (SMC) as a carrier and achieve controlled release of the drug by utilizing double-layer osmotic pump technology to improve the oral bioavailability. METHODS: FNB was loaded into the mesoporous of NMS by adsorption method to prepare the drug loading system (FNB-SMC). Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXDR) were used to characterize the present state of the drug before and after being loaded. The dissolution rate of FNB-SMC was investigated by in vitro dissolution test, and the formulation of the double-layer osmotic pump tablets of FNB-SMC was optimized. The oral bioavailability of the self-made tablet was investigated by in vivo experiment in rabbits. RESULTS: FNB existed in the mesoporous of SMC in an amorphous state. The in vitro dissolution test showed that NMS could significantly increase the dissolution rate of FNB, and the double-layer osmotic pump technology could achieve Zero-order release of the drug. The in vivo experiments showed that the oral bioavailability of the self-made tablets was significantly improved. CONCLUSION: The combination of starch source mesoporous carbon carrier and double-layer osmotic pump technology prevente the burst effect and significantly improve the oral absorption of FNB.
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Objective To construct an electrochemical immunosensor for ultrasensitive determination of myeloperoxidase (MPO) .Methods The electrochemical immunosensor for M PO was prepared by modifying the electrode using Au-graphitized me-soporous carbon nanoparticles(AuNPs@ GMCs) hybrid and immobilizing MPO antibodies onto the glass carbon electrode surface . The effect of experimental parameters on the immunosensor and results comparison with ELISA were investigated .Results The immunosensor was sensitive to M PO with a linear relationship between 2 .000 and 300 .000 ng/mL and a correlation coefficient of 0 .999 ;the detection limit was 0 .5 ng/mL .The correlation coefficient of two methods was 0 .983 .Conclusion The immunosensor can be used for ultrasensitive detection of MPO .
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Objective To prepare oxidized mesoporous carbon nanospheres and investigate potential application as drug delivery carriers for paclitaxel .Methods Physicochemical properties such as morphology ,diameter ,pore diameter and pore volume were characterized .Drug‐loading capacity was measured and drug release behavior in vitro was investigated by dialysis method .In vitro antitumour effect was evaluated by CCK‐8 methods .Results The synthesized oxidized mesoporous carbon nanospheres had an average diameter of 140 nm ,Zeta potential of -36 mV ,high specific surface area of 704.63 m2/g ,high drug‐loading capacity of 45 .6% .Conclusion Oxidized mesoporous carbon nanospheres have promising application in anti‐cancer drug delivery system .