Chongqing Medical and Health School

Fuling, China

Chongqing Medical and Health School

Fuling, China
SEARCH FILTERS
Time filter
Source Type

Tian F.,Southwest University | Huang W.,Southwest University | Yang J.,Southwest University | Yang J.,Chongqing Three Gorges University | Li Q.,ChongQing Medical and Health School
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

In pH 3.25-3.35 Britton-Robinson (BR) buffer solution, albendazole (ABZ) could react with eosin Y (EY) to form a 1:1 ion-association complex, which not only results in the quenching of fluorescence, but also resulted in the great enhancement of resonance Rayleigh scattering (RRS) and frequency doubling scattering (FDS). Furthermore, a new RRS spectrum will appear, and the maximum RRS wavelength was located at about 356 nm. The detection limit for ABZ were 21.51 ng mL-1 for the fluorophotometry, 6.93 ng mL -1 for the RRS method and 12.89 ng mL- 1 for the FDS method. Among them, the RRS method had the highest sensitivity. The experimental conditions were optimized and effects of coexisting substances were evaluated. Meanwhile, the influences of coexisting substances were tested. The methods have been successfully applied to the determination of ABZ in capsules and human urine samples. The composition and structure of the ion-association complex and the reaction mechanism were discussed. © 2014 Elsevier B.V. All rights reserved.


Tan X.,Southwest University | Yang J.,Southwest University | Yang J.,Chongqing Three Gorges University | Yang J.,Yangtze Normal University | And 2 more authors.
Analyst | Year: 2015

This paper reports a quantum dot (QD)-based "off-on" fluorescent biosensor specifically for the determination of glutathione (GSH) with high sensitivity. The biosensor was based on the following two properties. Firstly, the high fluorescence of N-acetyl-l-cysteine (NALC) capped CdTe QDs could be effectively quenched by Hg2+ due to the binding of Hg2+ to the NALC on the surface of the QDs and the electron transfer from the photoexcited NALC-capped CdTe QDs to Hg2+. Secondly, in the presence of GSH, the fluorescence intensity of NALC-capped CdTe QDs was found to be efficiently recovered. Under some optimized conditions, the relatively restored fluorescence intensity was proportional to the concentration of GSH in the range of 4-64 μg mL-1, with a correlation coefficient of 0.9980 and a limit of detection of 2.49 ng mL-1. In addition, the established method shows a high selectivity for some amino acids except cysteine. Moreover, to further investigate its performance, the biosensor was applied to the determination of GSH in human serum samples through a standard addition method and determination of normal GSH concentration in original human serum samples with satisfactory results. © The Royal Society of Chemistry 2015.


Tan X.,Southwest University | Li Q.,Chongqing Medical and Health School | Zhang X.,Paine College | Shen Y.,Southwest University | And 2 more authors.
RSC Advances | Year: 2015

A new fluorescence sensor for the determination of thioctic acid (TA) in aqueous media based on the recovered fluorescence of N-acetyl-l-cysteine capped CdTe quantum dots [NALC-CdTe QDs]-Cu2+ system was proposed. The fluorescence intensity of NALC-CdTe QDs was quenched by Cu2+ due to the binding of Cu2+ to NALC on the surface of the QDs. However, in the presence of TA, the fluorescence intensity of NALC-CdTe QDs was found to be efficiently recovered. Experimental results showed that the pH of the buffer solution and the concentration of Cu2+ affected the fluorescence intensity upon adding TA. Under the optimal conditions, the recovered fluorescence intensity was linearly proportional to the increasing TA concentration in the range 4-120 μg mL-1. In addition, among the other biologically relevant chemical species that were tested, only TA could turn on the fluorescence intensity suggesting that the [NALC-CdTe QDs]-Cu2+ system was a highly selective sensor for TA. Moreover, to further investigate the performance of the perfect analysis, the developed biosensor was applied to the determination of TA in its commercial samples and detected TA in the blood of a rabbit with the time extended. © The Royal Society of Chemistry 2015.


Li Q.,Chongqing Medical and Health School | Tan X.,Southwest University | Li J.,Chongqing Medical and Health School | Pan L.,Chongqing Medical and Health School | Liu X.,Chongqing Medical and Health School
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

Water-soluble glutathione (GSH)-capped CdTe quantum dots (QDs) were synthesized. In pH 7.1 PBS buffer solution, the interaction between GSH-capped CdTe QDs and fenbendazole (FBZ) was investigated by spectroscopic methods, including fluorescence spectroscopy, ultraviolet-visible absorption spectroscopy, and resonance Rayleigh scattering (RRS) spectroscopy. In GSH-capped CdTe QDs solution, the addition of FBZ results in the fluorescence quenching and RRS enhancement of GSH-capped CdTe QDs. And the quenching intensity (enhanced RRS intensity) was proportional to the concentration of FBZ in a certain range. Investigation of the interaction mechanism, proved that the fluorescence quenching and RRS enhancement of GSH-capped CdTe QDs by FBZ is the result of electrostatic attraction. Based on the quenching of fluorescence (enhancement of RRS) of GSH-capped CdTe QDs by FBZ, a novel, simple, rapid and specific method for FBZ determination was proposed. The detection limit for FBZ was 42 ng mL-1 (3.4 ng mL-1) and the quantitative determination range was 0-2.8 μg mL-1 with a correlation of 0.9985 (0.9979). The method has been applied to detect FBZ in real simples and with satisfactory results. © 2015 Elsevier B.V.


Li Q.,Chongqing Medical and Health School | Tan X.,Southwest University | Fu L.,Chongqing Medical and Health School | Liu Q.,Chongqing Medical and Health School | Tang W.,Chongqing Medical and Health School
Analytical Methods | Year: 2015

Glutathione (GSH)-capped CdTe QDs with diameters of 3 nm were synthesised. The interaction between the QDs and albendazole (ABZ) was investigated by UV-vis absorption, resonance Rayleigh scattering (RRS) and fluorescence spectroscopy. Based on changes in the UV-vis absorption spectra of QDs and ABZ, we demonstrated that the QDs associated with ABZ to form new complexes. In pH 7.1 PBS buffer solution, the fluorescence intensity of QDs was effectively quenched by ABZ. The fluorescence quenching of QDs by ABZ mainly results from the QDs-ABZ complexes, and the electrostatic attraction played a major role in stabilising these complexes. Furthermore, the interaction between QDs and ABZ led to a remarkable enhancement in RRS, which was proportional to the ABZ concentration within a certain concentration range. The suitable reaction conditions, important factors as well as the influence of coexisting substances were studied. The possible reaction mechanism was also discussed. This journal is © The Royal Society of Chemistry.


PubMed | Chongqing Medical and Health School, Southwest University and Chongqing Three Gorges University
Type: Journal Article | Journal: Luminescence : the journal of biological and chemical luminescence | Year: 2016

A novel method that uses acridine orange (AO) to detect indigo carmine (IC) in soft drinks was developed. The method is highly sensitive and is based on a resonance Rayleigh scattering (RRS) technique. In Britton-Robinson (BR) buffer solution, pH4.3, the weak RRS intensity of AO was greatly enhanced by the addition of IC, with the maximum peak located at 332nm. Under optimum conditions, it was found that the enhanced RRS intensity was proportional to the concentration of IC over a range of 2-3210(-6) mol/L. A low detection limit of 2.410(-8) mol/L was achieved. The sensitivity and selectivity of the method are high enough to permit the determination of trace amounts of IC without any significant interference from high levels of other components such as common anions and other amino acids. Finally, the concentration of IC in three different soft drinks was determined with satisfactory results. Copyright 2016 John Wiley & Sons, Ltd.


PubMed | Yangtze Normal University, Chongqing Medical and Health school, Chongqing Three Gorges University and Southwest University
Type: | Journal: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy | Year: 2016

Four simple and accurate spectrophotometric methods were proposed for the simultaneous determination of three -adrenergic blockade, e.g. atenolol, metoprolol and propranolol. The methods were based on the reaction of the three drugs with erythrosine B (EB) in a Britton-Robinson buffer solution at pH4.6. EB could combine with the drugs to form three ion-association complexes, which resulted in the resonance Rayleigh scattering (RRS) intensity that is enhanced significantly with new RRS peaks that appeared at 337 nm and 370 nm, respectively. In addition, the fluorescence intensity of EB was also quenched. The enhanced scattering intensities of the two peaks and the fluorescence quenched intensity of EB were proportional to the concentrations of the drugs, respectively. What is more, the RRS intensity overlapped with the double-wavelength of 337 nm and 370 nm (so short for DW-RRS) was also proportional to the drugs concentrations. So, a new method with highly sensitive for simultaneous determination of three bisoprolol drugs was established. Finally, the optimum reaction conditions, influencing factors and spectral enhanced mechanism were investigated. The new DW-RRS method has been applied to simultaneously detect the three -blockers in fresh serum with satisfactory results.


PubMed | Chongqing Medical and Health School and Southwest University
Type: | Journal: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy | Year: 2015

Water-soluble glutathione (GSH)-capped CdTe quantum dots (QDs) were synthesized. In pH 7.1 PBS buffer solution, the interaction between GSH-capped CdTe QDs and fenbendazole (FBZ) was investigated by spectroscopic methods, including fluorescence spectroscopy, ultraviolet-visible absorption spectroscopy, and resonance Rayleigh scattering (RRS) spectroscopy. In GSH-capped CdTe QDs solution, the addition of FBZ results in the fluorescence quenching and RRS enhancement of GSH-capped CdTe QDs. And the quenching intensity (enhanced RRS intensity) was proportional to the concentration of FBZ in a certain range. Investigation of the interaction mechanism, proved that the fluorescence quenching and RRS enhancement of GSH-capped CdTe QDs by FBZ is the result of electrostatic attraction. Based on the quenching of fluorescence (enhancement of RRS) of GSH-capped CdTe QDs by FBZ, a novel, simple, rapid and specific method for FBZ determination was proposed. The detection limit for FBZ was 42 ng mL(-1) (3.4 ng mL(-1)) and the quantitative determination range was 0-2.8 g mL(-1) with a correlation of 0.9985 (0.9979). The method has been applied to detect FBZ in real simples and with satisfactory results.


PubMed | Chongqing Medical and Health School and Chongqing Medical University
Type: Journal Article | Journal: Oncology reports | Year: 2016

Previous research has shown that total saponins of Panax ginseng (TSPG) and other ginsenoside monomers inhibit the proliferation of leukemia cells. However, the effect has not been compared among them. Cell viability was determined by Cell Counting Kit-8 assay, and ultra-structural characteristics were observed under transmission electron microscopy. Cell cycle distribution and apoptosis were determined by flow cytometry (FCM). Real-time fluorescence quantitativePCR, western blotting and immunofluorescence were used to measure the expression of -catenin, TCF4, cyclinD1 and NF-Bp65. -catenin/TCF4 target gene transcription were observed by ChIP-PCR assay. We found that 20(S)-ginsenoside Rh2 [(S)Rh2] inhibited the proliferation of KG-1a cells more efficiently than the other monomers. Moreover, (S)Rh2 arrested KG-1a cells in the G0/G1 phase and induced apoptosis. In addition, the levels of -catenin, TCF4, cyclinD1 mRNA and protein were decreased. The ChIP-PCR showed that (S)Rh2 downregulated the transcription of -catenin/TCF4 target genes, such as cyclinD1 and c-myc. These results indicated that (S)Rh2 induced cell cycle arrest and apoptosis through the Wnt/-catenin signaling pathway, demonstrating its potential as a chemotherapeutic agent for leukemia therapy.


PubMed | Chongqing Medical and Health School and Chongqing Medical University
Type: | Journal: Chemico-biological interactions | Year: 2015

Activation and abnormal expression of histone deacetylase (HDAC) which is important target for cancer therapeutics are related to the occurrence of human leukemia. 20(s)-Ginsenoside Rh2 (20(s)-Rh2) may be a potential HDAC inhibitor (HDACi) of leukemia, but the mechanism has not been reported.The cell proliferation and apoptosis was assessed in cultured K562 and KG-1 cells. The protein expression was measured with immunoblotting. The activities of HDAC and histone acetyltransferase (HAT) were measured with BCA. In vivo experiments were performed on naked mice carrying K562 cells for assessment of tumor growth, apoptosis, protein expression, and HDAC/HAT activities.20(s)-Rh2 effectively induced cell cycle arrest at G0/G1 phase and apoptosis in K562 and KG1- cells, decreased the levels of proteins associated with cell proliferation (Cyclin D1, Bcl-2, ERK, p-ERK) and activated pro-apoptotic proteins (Bax, cleaved Caspase-3, p38, p-p38, JNK, p-JNK). 20(s)-Rh2 down-regulated HDAC1, HDAC2, HDAC6, increased histone H3 acetylation and HAT activity. Moreover, 20(s)-Rh2 inhibited the growth of human leukemia xenograft tumors in vivo.20(s)-Rh2 inhibited the proliferation of K562 and KG1- cell by reducing the expression and activity of HDACs, increasing histone acetylation, and regulating key proteins in the downstream signaling pathways. Therefore, 20(s)-Rh2 could become a potential natural HDACi for chemotherapy of leukemia.

Loading Chongqing Medical and Health School collaborators
Loading Chongqing Medical and Health School collaborators