The urea denatured recombinant human granulocyte colony-stimulating factor (rhG- CSF) which was expressed in Escheriachia coli (E. coli) was refolded with simultaneous purification by strong anion exchange chromatogra...The urea denatured recombinant human granulocyte colony-stimulating factor (rhG- CSF) which was expressed in Escheriachia coli (E. coli) was refolded with simultaneous purification by strong anion exchange chromatography (SAX) in the presence of low concentration- of urea. The effect of urea concentration on this refolding process was investigated. The obtained refolded rhG-CSF has a high specific activity of 2.3×108 U/mg, demonstrating that the proteins were completely refolded during the chromatographic process. With only one step by SAX in 40 min, purity and mass recovery of the refolded and purified rhG-CSF were 97% and 43%, respectively.展开更多
A simple, fast and reliable method, using high performance anion chromatography with pulsed amperometric detection, had been developed for the analysis of neomycin in water samples. The elution and separation were car...A simple, fast and reliable method, using high performance anion chromatography with pulsed amperometric detection, had been developed for the analysis of neomycin in water samples. The elution and separation were carried out with an isocratic mobile phase, containing 10 mmol/L NaOH. The influence of the concentration and pH of the mobile phase on the separation and detection was investigated. A quadruple-potential waveform used for the detection was optimized. The detection limit of neomycin was down to 0.027 μg/mL. The linearity of neomycin calibration curve ranged from 0.050 to 0.505 μg/mL with correlation coefficient of 0.9997. R.S.D. (n = 11) was 4.0%.展开更多
A La^3＋-Cu/Pt modified electrode was fabricated by electrodepositing process in CuS04 solution by adding a small amount of lanthium compound, and it was employed for direct current （DC） amperometric detection of sp...A La^3＋-Cu/Pt modified electrode was fabricated by electrodepositing process in CuS04 solution by adding a small amount of lanthium compound, and it was employed for direct current （DC） amperometric detection of spectinomycin by anion-exchange chromatography. Without derivatization, this method can simultaneously determine the main component and impurities in spectinomycin pharmaceutical raw material. Ease of preparation, being applied in DC detection mode and good catalytic stability confirmed the interests of this modified electrode as amperometric sensor for the determination of spectinomycin.展开更多
A rapid and practical method for direct detection of zidovudine in high performance anion exchange chromatography （HPAEC） has been developed with integrated pulsed amperometric detection （IPAD）. Dionex AS18 （250m...A rapid and practical method for direct detection of zidovudine in high performance anion exchange chromatography （HPAEC） has been developed with integrated pulsed amperometric detection （IPAD）. Dionex AS18 （250mm × 2mm） and AG18 （50 mm× 2 mm） columns and 11 mmol/L NaOH solution were used for separation. Multi-step potential waveform parameters were optimized to maximize the signal-to-noise ratio （S/N）. Utilizing an optimized waveform, the repeatability （intra-day） precision and intermediate （inter-day） precision are obtained with relative standard deviation （RSD） of 1.88, 2.27, respectively. The limit of quantification （LOQ） and limit of detection （LOD） were found to be 9.70, 3.0 ng/mL, respectively, with correlation coefficients of 0.9992 over concentration range 0.01-10 μg/mL. The present method was successfully applied to the determination of zidovudine in human plasma. The recoveries of plasma sample spiked by 0.7 μg/mL, 2.7 μg/mL obtained were 95.3-101.5%, with relative standard deviation （RSD） of 2.54%, 2.21%, respectively.展开更多
基金This work is supported by the National Natural Science Foundation of China(No．20175016)
文摘The urea denatured recombinant human granulocyte colony-stimulating factor (rhG- CSF) which was expressed in Escheriachia coli (E. coli) was refolded with simultaneous purification by strong anion exchange chromatography (SAX) in the presence of low concentration- of urea. The effect of urea concentration on this refolding process was investigated. The obtained refolded rhG-CSF has a high specific activity of 2.3×108 U/mg, demonstrating that the proteins were completely refolded during the chromatographic process. With only one step by SAX in 40 min, purity and mass recovery of the refolded and purified rhG-CSF were 97% and 43%, respectively.
文摘A simple, fast and reliable method, using high performance anion chromatography with pulsed amperometric detection, had been developed for the analysis of neomycin in water samples. The elution and separation were carried out with an isocratic mobile phase, containing 10 mmol/L NaOH. The influence of the concentration and pH of the mobile phase on the separation and detection was investigated. A quadruple-potential waveform used for the detection was optimized. The detection limit of neomycin was down to 0.027 μg/mL. The linearity of neomycin calibration curve ranged from 0.050 to 0.505 μg/mL with correlation coefficient of 0.9997. R.S.D. (n = 11) was 4.0%.
基金supported by National Natural Science Foundation of China(No.20775070)Zhejiang Provincial Natural Science Foundation of China(No.Y407153)sponsored by Zhejiang Provincial Assay Foundation of China(No.2007F70017)
文摘A La^3＋-Cu/Pt modified electrode was fabricated by electrodepositing process in CuS04 solution by adding a small amount of lanthium compound, and it was employed for direct current （DC） amperometric detection of spectinomycin by anion-exchange chromatography. Without derivatization, this method can simultaneously determine the main component and impurities in spectinomycin pharmaceutical raw material. Ease of preparation, being applied in DC detection mode and good catalytic stability confirmed the interests of this modified electrode as amperometric sensor for the determination of spectinomycin.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.Y2110945)Zhejiang Provincial Analysis and Testing Foundation of China(No.2011C37065)
文摘A rapid and practical method for direct detection of zidovudine in high performance anion exchange chromatography （HPAEC） has been developed with integrated pulsed amperometric detection （IPAD）. Dionex AS18 （250mm × 2mm） and AG18 （50 mm× 2 mm） columns and 11 mmol/L NaOH solution were used for separation. Multi-step potential waveform parameters were optimized to maximize the signal-to-noise ratio （S/N）. Utilizing an optimized waveform, the repeatability （intra-day） precision and intermediate （inter-day） precision are obtained with relative standard deviation （RSD） of 1.88, 2.27, respectively. The limit of quantification （LOQ） and limit of detection （LOD） were found to be 9.70, 3.0 ng/mL, respectively, with correlation coefficients of 0.9992 over concentration range 0.01-10 μg/mL. The present method was successfully applied to the determination of zidovudine in human plasma. The recoveries of plasma sample spiked by 0.7 μg/mL, 2.7 μg/mL obtained were 95.3-101.5%, with relative standard deviation （RSD） of 2.54%, 2.21%, respectively.
