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Gong A.,Yangzhou University | Gong A.,Yangzhou Polytechnic Institute | Ping W.,Yangzhou University | Wang J.,Yangzhou University | Zhu X.,Yangzhou University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

In this paper, carboxymethyl-hydroxypropyl-β-cyclodextrin polymer modified magnetic particles Fe3O4 (CM-HP-β-CDCP-MNPs) were prepared and applied to magnetic solid phase extraction of rutin combined with UV-visible spectrometry detection. The synthesized magnetic particles were characterized by element analysis, Fourier transform infrared spectra, thermal gravimetric analysis, and transmission electron microscopy. Several variables affecting the extraction and desorption of rutin such as pH, the amount of adsorbent, the type and volume of eluent, extraction and desorption time, and temperature were investigated. The maximum adsorption capacity was 67.0 mg g-1 for rutin with the equilibrium time of 30 min at room temperature, and the adsorbent could be reused for 10 times. A calibration curve was linear in the range of 0.05-8.00 μg mL-1 with a relative standard deviation of 2.9% (n = 5, c = 4.0 μg mL-1). The limit of detection was 7.0 ng mL-1. The interaction mechanism between the adsorbent and rutin was also studied. Feasibility of this method was validated by the analysis of rutin tablets and lotus plumule. ©.

Gong A.,Yangzhou University | Gong A.,Yangzhou Polytechnic Institute | Zhu X.,Yangzhou University
Talanta | Year: 2014

In this paper, a simple and efficient ultrasound-assisted ionic liquid dispersive liquid-liquid microextraction (UA IL-DLLME) coupled with high-performance liquid chromatography for the analysis of ulipristal acetate (UPA) was developed. UPA could be easily migrated into 1-octyl-3-methylimidazolium hexafluorophosphate [C8mimPF6] IL phase without dispersive solvent. The research of extraction mechanism showed that hydrophobic interaction force played a key role in the IL-DLLME. Several important parameters affecting the extraction recovery were optimized. Under the optimized conditions, 25-fold enrichment factor was obtained and the limit of detection (LOD) was 6.8 ng mL-1 (tablet) or 9.3 ng mL-1 (serum) at a signal-to-noise ratio of 3. The calibration curve was linear over the range of 0.03-6.0 μg mL-1. The proposed method was successfully applied to the UPA tablets and the real mice serum samples. © 2014 Elsevier B.V. All rights reserved.

Gong A.,Yangzhou University | Gong A.,Yangzhou Polytechnic Institute | Zhu X.,Yangzhou University
Journal of Fluorescence | Year: 2013

A novel spectrofluorimetric method to determine abiraterone acetate and its active metabolite, abiraterone was developed, based on the fact that fluorescence intensity of abiraterone acetate and abiraterone could be enhanced in β-cyclodextrin (β-CD) due to the formation of the inclusion complex. The inclusion interaction of β-CD and abiraterone acetate and the β-cyclodextrin sensitized spectrofluorimetry was examined. The various factors influencing fluorescence were discussed in details. The results showed that under the optimized conditions, the linear range of calibration curve for the determination of biraterone acetate and abiraterone was 0.20 ~ 6.0 μg/mL, and the detection limit (LOD) was 6.8 (r = 0.997) or 6.6 ng/mL (r = 0.996), respectively. No interference was observed from common co-existing substances or pharmaceutical excipient. The method was successfully applied to the analysis of abiraterone acetate in pharmaceutical formulation and abiraterone in human serum/urine. © 2013 Springer Science+Business Media New York.

Gong A.,Yangzhou University | Gong A.,Yangzhou Polytechnic Institute | Zhu X.,Yangzhou University
Fluid Phase Equilibria | Year: 2014

A novel separation/analysis method was developed for the determination of dutasteride in a pharmaceutical formulation and biological samples, which based on surfactant dodecyl sodium sulfate (SDS)/ionic liquid 1-hexyl-3-methylimidazolium bromide (IL, [C6min]Br) aqueous two-phase system (ATPS) extraction coupled with spectrofluorimetry. The ATPS was formed owing to new ordered molecular assembly SDS/IL, which not only extracted dutasteride but also sensitized its fluorescence intensity due to synergistic sensitizing effect. Under optimum conditions, a linear calibration curve was obtained in the range of 0.016-0.64μgmL-1 with r=0.9991 (n=8). The detection limit was 2.2ngmL-1. The preconcentration factor was 7.5. The proposed green analytical procedure was satisfactorily applied to the analysis of dutasteride in dutasteride soft gelatin capsule and human serum with the recovery of 96.7-108.0%. The obtained results of this work were in good agreement with the results of HPLC. The extraction mechanism ATPS-based was also discussed. © 2014 Elsevier B.V.

Gong A.-Q.,Yangzhou University | Gong A.-Q.,Yangzhou Polytechnic Institute | Zhu X.-S.,Yangzhou University
Journal of Pharmaceutical Analysis | Year: 2013

A rapid, novel spectrofluorimetric method to determine epristeride (EP) in biological fluids and a pharmaceutical formulation was developed, based on the fact that fluorescence intensity of l-tryptophan could be quenched by EP in the medium of pH=9.0. The various factors influencing fluorescence quenching were discussed. The quenching mechanism was investigated with the quenching type, synchronous fluorescence spectra and quantum efficiency. Under the optimized conditions, fluorescence quenching value (ΔF=Fl-tryptophan- FEP-l-tryptophan) showed a good linear relationship with the EP concentration ranging from 0.4 to 12.0 μg/mL. The linearity, recovery and limit of detection demonstrated that the proposed method was suitable for EP determination in biological fluids and EP tablets. The method was successfully applied to the analysis of EP in real samples and the obtained results were in good agreement with the results of the official method. © 2013 Xi'an Jiaotong University.

Xu B.,Yangzhou Polytechnic Institute
Materials Research Innovations | Year: 2013

Poly(o-phenylenediamine) (POPD) hollow microspheres with Ag submicrometre particles decorated on both inner and outer surfaces of shells as Ag/POPD hollow hybrids have been successfully fabricated through the reduction of AgNO 3 by ascorbic acid in aqueous solution containing POPD hollow microspheres. Poly(o-phenylenediamine) hollow microspheres with functional amine groups on surfaces of polymer shells are chosen as supporter for Ag particles. Ag/POPD hollow hybrids are characterised by Fourier transform infrared and X-ray diffraction spectroscopy techniques. Formation mechanisms involved have been proposed according to experimental results. Furthermore, catalytic activities of Ag/POPD hollow hybrids towards the reduction of 4-nitrophenol in the presence of NaBH4 have also been investigated. © W. S. Maney & Son Ltd. 2013.

Chen J.,Yangzhou Polytechnic Institute
Bandaoti Guangdian/Semiconductor Optoelectronics | Year: 2014

A drive module of LED constant current source with the output power of about 50 W was designed, and the load is a LED array consisting of multiple hybrid LED tubes, and the power of each LED is 1 W. By designing and manufacturing of the current-mode flyback converter and constant current control circuit, tests with different loads under different input voltages indicate that the current change laws are similar for each condition. As the load decreases, the output voltage increases but the output current decreases, the output current stability will be up to 4.6%. Under a certain load and the output voltage maintaining at around 47.2 V, the voltage ripple peak-peak value will be approximately 400 mV. The current fluctuation is about 0.05 A, and the output current is stable and reliable, which can be used for power supply of multiple hybrid LED array.

Xu B.,Yangzhou Polytechnic Institute
Journal of the Chinese Chemical Society | Year: 2010

The adsorption behavior of metal cations on gold nanoparticles was investigated by isothermal titration microcalorimetry (ITC) for the first time, and verified by transmission electron microscopy (TEM), and UV absorption spectroscopy. When transition metal cations were injected into the gold colloids, a binding isotherm with a sigmoidal response was obtained; and when instead of alkaline earth cations, the binding isotherm changed from the overall exothermic to endothermic nature. The binding enthalpy depends on the nature and concentration of added cations. The interactions of metal cations with the surface gold atoms and the COO- group of citrate salt that weakly bound on gold nanoparticles are the driving force for the binding; and the binding process is enthalpically driven. TEM images indicate that the addition of metal cations results in the growth and aggregation of gold nanoparticles. After the metal cations were added to the gold colloids, the intensity of the surface plasmon resonance adsorption band at 523 nm of gold nanoparticles decreased, and a new absorption at around 610 nm appeared. This is attributed to gold nanoclusters induced by the surface binding of the metal cations on gold nanoparticles, which is further confirmed by ITC results.

Chen L.-P.,Yangzhou Polytechnic Institute
Gongneng Cailiao/Journal of Functional Materials | Year: 2013

Nanocrystalline indium hydroxides with the different shape and size were synthesized by using polymer PEG as the water-soluble growth medium. The size of indium hydroxides decreased with the increase of PEG concentration, and the morphologies of particles changed from inhomogeneity nanosheets to uniform nanosheets. Nanocrystalline indium oxide nanosheets were obtained upon calcination at the temperature of 600°C over 3.5 h. The morphology, size and phase structure of indium oxide nanosheets were characterized by scan electron microscopy, transmission electron microscopy, X-ray diffraction and FT-IR spectra. The results showed that the diameters of the as-prepared indium oxide nanosheets were about 30-50 nm length and the as-prepared samples with cube structure were uniform in size, well dispersed and of high purity.

Zhang J.,Yangzhou Polytechnic Institute
Advanced Materials Research | Year: 2011

In this paper, Portland cement was used as cementitious material and expanded perlite was used as insulation material. Fatty acid salt water repellent was also added to make this new thermal insulation, waterproof and light weight roof building material. It can be cast onto flat roof during construction or made into tiles and laid onto sloping roofs. This new roof building material had short construction period and can be completed in a one-time process. It may replace conventional construction method of applying insulation and waterproof materials separately. © (2011) Trans Tech Publications, Switzerland.

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