Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitativ...Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.展开更多
An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile p...An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile phase was consisted of acetonitrile-0.1%triethylamine water(1:99,v/v).The liner range for biapenem quantification was 0.05-10.0 mg/mL(r^2= 0.999). The LOD and LOQ of impurity were 4.8 ng(S/N = 3) and 18.5 ng(S/N = 10),respectively.Intra-day RSD of main impurity and total impurity were 1.84%and 3.37%(n = 3);inter-day RSD of main impurity and total impurity were 4.84%and 7.58% (n = 9).The test solution was stable when stored at 4℃for 6 h.The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography-diode array detection data from the quality control method by calculating correlation coefficients without reference standards.Two hydrolysis degradation products with relative retention times(RRTs) of 0.528 and 0.743,two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram.It provides a new way to identify impurity peaks by the routine HPLC-UV method.展开更多
A simple high-performance liquid chromatography （HPLC） method was established and subsequently used to study the pharmacokinetics of biapenem in healthy volunteers. Chromatography separation was carried out using a ...A simple high-performance liquid chromatography （HPLC） method was established and subsequently used to study the pharmacokinetics of biapenem in healthy volunteers. Chromatography separation was carried out using a C18 reverse-phase column with an isocratic mobile phase consisting of 0.05 M ammonium acetate-methanol, either for plasma （94：6, v/v, and flow rate 1.0 mL/min） or for urine samples （97.5：2.5, v/v, flow rate 1.5 mL/min）. The UV detector was set at 300 nm. The assay was linear over the range of 0.25 mg/L-50 mg/L for plasma samples and 0.50 mg/L-200 mg/L for urine samples. The intra-day and inter-day RSD values were lower than 2.8% and 4.6%, respectively, for biapenem in plasma, 2.4% and 2.5%, respectively, for biapenem in urine. Biapenem was stable at room temperature for up to 6 h in plasma and 8 h in urine when MOPS was added immediately after sample collection. An intravenous single dose of 600 mg biapenem was administered to 12 healthy male volunteers. The pharmacokinetic parameters were calculated by Winnonlin with a noncompartment model. The pharmacokinetic parameters were obtained as following： Cmax 37±6 mg/L, t1/2 1.27±0.21 h, AUC0-8h 56±8 mg/L/h, and AUC0-∞57±8 mg/L/h. The accumulated urine excretion rate in 24 h was 58%±5%. The established HPLC method was validated and suitable for the pharmacokinetic study of biapenem.展开更多
An HPLC method for routine quality control of biapenem was established. A Dikma Diamonsil Cls column （250 mm× 4.6 mm, 5 μm） was used with diode array detection and single wavelength detection at 220 mm. The mo...An HPLC method for routine quality control of biapenem was established. A Dikma Diamonsil Cls column （250 mm× 4.6 mm, 5 μm） was used with diode array detection and single wavelength detection at 220 mm. The mobile phase was consisted of acetonitrile-0 1% triethylamine water （1：99, v/v）. The liner range for biapenem quantification was 0.05-10.0 mg/mL （r2- 0.999）. The LOD and LOQ of impurity were 4.8 ng （S/N 3） and 18.5 ng （S/N = 10）, respectively. Intra-day RSD of main impurity and total impurity were 1.84% and 3.37% （n = 3）; inter-day RSD of main impurity and total impurity were 4.84% and 7.58% （n = 9）. The test solution was stable when stored at 4 ℃ for 6 h. The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography~tiode array detection data from the quality control method by calculating correlation coefficients without reference standards. Two hydrolysis degradation products with relative retention times （RRTs） of 0.528 and 0.743, two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram. It provides a new way to identify impurity peaks by the routine HPLC-UV method.展开更多
Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Myc...Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Mycobacterium tuberculosis(Mtb) multidrug-resistant(MDR) isolates, extensively drug-resistant(XDR) isolates, and the H37 RV strain. BP/CL activity against the H37 Rv strain was assessed in liquid cultures, in macrophages, and in mice. Results BP/CL exhibited activity against MDR and XDR Mtb isolates in liquid cultures. BP/CL treatment significantly reduced the number of colony forming units(CFU) of Mtb within macrophages compared with control untreated infected macrophages. Notably, BP/CL synergized in pairwise combinations with protionamide, aminosalicylate, and capreomycin to achieve a fractional inhibitory concentration for each pairing of 0.375 in vitro. In a mouse tuberculosis infection model, the efficacy of a cocktail of levofloxacin + pyrazinamide + protionamide + aminosalicylate against Mtb increased when the cocktail was combined with BP/CL, achieving efficacy similar to that of the positive control treatment(isoniazid + rifampin + pyrazinamide) after 2 months of treatment. Conclusion BP/CL may provide a new option to clinically treat MDR tuberculosis.展开更多
基金National Natural Science Foundation of China (Grant No.30973597)
文摘Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.
基金National Key New Drug R&D Program Foundation of China(Grant No.2009ZX09313-027).
文摘An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile phase was consisted of acetonitrile-0.1%triethylamine water(1:99,v/v).The liner range for biapenem quantification was 0.05-10.0 mg/mL(r^2= 0.999). The LOD and LOQ of impurity were 4.8 ng(S/N = 3) and 18.5 ng(S/N = 10),respectively.Intra-day RSD of main impurity and total impurity were 1.84%and 3.37%(n = 3);inter-day RSD of main impurity and total impurity were 4.84%and 7.58% (n = 9).The test solution was stable when stored at 4℃for 6 h.The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography-diode array detection data from the quality control method by calculating correlation coefficients without reference standards.Two hydrolysis degradation products with relative retention times(RRTs) of 0.528 and 0.743,two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram.It provides a new way to identify impurity peaks by the routine HPLC-UV method.
文摘A simple high-performance liquid chromatography （HPLC） method was established and subsequently used to study the pharmacokinetics of biapenem in healthy volunteers. Chromatography separation was carried out using a C18 reverse-phase column with an isocratic mobile phase consisting of 0.05 M ammonium acetate-methanol, either for plasma （94：6, v/v, and flow rate 1.0 mL/min） or for urine samples （97.5：2.5, v/v, flow rate 1.5 mL/min）. The UV detector was set at 300 nm. The assay was linear over the range of 0.25 mg/L-50 mg/L for plasma samples and 0.50 mg/L-200 mg/L for urine samples. The intra-day and inter-day RSD values were lower than 2.8% and 4.6%, respectively, for biapenem in plasma, 2.4% and 2.5%, respectively, for biapenem in urine. Biapenem was stable at room temperature for up to 6 h in plasma and 8 h in urine when MOPS was added immediately after sample collection. An intravenous single dose of 600 mg biapenem was administered to 12 healthy male volunteers. The pharmacokinetic parameters were calculated by Winnonlin with a noncompartment model. The pharmacokinetic parameters were obtained as following： Cmax 37±6 mg/L, t1/2 1.27±0.21 h, AUC0-8h 56±8 mg/L/h, and AUC0-∞57±8 mg/L/h. The accumulated urine excretion rate in 24 h was 58%±5%. The established HPLC method was validated and suitable for the pharmacokinetic study of biapenem.
基金Foundation item： National Key New Drag R＆D Program Foundation of China （Grant No. 2009ZX09313-027）.
文摘An HPLC method for routine quality control of biapenem was established. A Dikma Diamonsil Cls column （250 mm× 4.6 mm, 5 μm） was used with diode array detection and single wavelength detection at 220 mm. The mobile phase was consisted of acetonitrile-0 1% triethylamine water （1：99, v/v）. The liner range for biapenem quantification was 0.05-10.0 mg/mL （r2- 0.999）. The LOD and LOQ of impurity were 4.8 ng （S/N 3） and 18.5 ng （S/N = 10）, respectively. Intra-day RSD of main impurity and total impurity were 1.84% and 3.37% （n = 3）; inter-day RSD of main impurity and total impurity were 4.84% and 7.58% （n = 9）. The test solution was stable when stored at 4 ℃ for 6 h. The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography~tiode array detection data from the quality control method by calculating correlation coefficients without reference standards. Two hydrolysis degradation products with relative retention times （RRTs） of 0.528 and 0.743, two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram. It provides a new way to identify impurity peaks by the routine HPLC-UV method.
基金supported by the Beijing Medical Award Foundation [YJHYXKYJJ-104]
文摘Objective To assess the activities of biapenem against multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis. Methods Biapenem/clavulanate(BP/CL) was evaluated for in vitro activity against Mycobacterium tuberculosis(Mtb) multidrug-resistant(MDR) isolates, extensively drug-resistant(XDR) isolates, and the H37 RV strain. BP/CL activity against the H37 Rv strain was assessed in liquid cultures, in macrophages, and in mice. Results BP/CL exhibited activity against MDR and XDR Mtb isolates in liquid cultures. BP/CL treatment significantly reduced the number of colony forming units(CFU) of Mtb within macrophages compared with control untreated infected macrophages. Notably, BP/CL synergized in pairwise combinations with protionamide, aminosalicylate, and capreomycin to achieve a fractional inhibitory concentration for each pairing of 0.375 in vitro. In a mouse tuberculosis infection model, the efficacy of a cocktail of levofloxacin + pyrazinamide + protionamide + aminosalicylate against Mtb increased when the cocktail was combined with BP/CL, achieving efficacy similar to that of the positive control treatment(isoniazid + rifampin + pyrazinamide) after 2 months of treatment. Conclusion BP/CL may provide a new option to clinically treat MDR tuberculosis.
