Study on Detection Methods for Related Substances in Fidaxomicin Raw Material / 中国药房

OBJECTIVE：To establish th e method for the determination of related substances in fidaxomicin raw material. METHODS：The detection ability of NP-HPLC-UV ，RP-HPLC-ELSD and RP-HPLC-UV systems for the related substances in fidamycin raw material was investigated and the best chromatographic system was selected . The HPLC detection method for the related substances was established. The detection was performed on Agilent Eclipse XDB C 18 column with mobile phase A consisted of 0.2％ triethylamine buffer solution （pH 3.8）-acetonitrile（55∶45，V/V），mobile phase B consisted of 0.2％ triethylamine buffer solution（pH 3.8）-acetonitrile（20∶80，V/V）at the flow rate of 1.0 mL/min（gradient elution ）；the detection wavelength was set at 230 nm，and column temperature was 35 ℃；the sample size was 10 µL. Calculation of the content of related substances was principal component self-control method without correction factor. RESULTS ：The impurities C and F could not be separated effectively in NP-HPLC-UV system. In RP-HPLC-ELSD system ，only impurities C ，D，E and F could be detected. In RP-HPLC-UV system ，11 impurities could be detected. In the study of methodology ，the linear ranges were 0.5-20.0 μg/mL for fidaxomicin（R2＝0.999 9）；the LOD was 0.05 ng，LOQ was 0.15 ng；RSDs of reproducibility and intermediate precision tests were less than 2.0％（n＝6）；average recovery was 98.4％（RSD＝3.6％，n＝9）. The sum of impurities in 3 batches of raw materials were 0.53％，0.51％，0.51％，respectively. CONCLUSIONS ：The effect of detecting impurities by RP-HPLC-UV are the best. Established method is specific and sensitive ，and can be used for the determination of related substance in fidaxomicin raw material.

Simultaneous estimation of rosuvastatin and amlodipine in pharmaceutical formulations using stability indicating HPLC method

A viable cost-effective and isocratic approach employing C-18 column (250 mm × 4.6 mm, 5 µm) based HPLC has been utilized to separate and estimate the drugs, rosuvastatin, amlodipine and their stress induced degradation products, simultaneously in pharmaceutical formulations. Focused on ICH guideline parameters, the efficient separation of both drugs and their degradation products was achieved by optimizing a 30:70 (v/v) solvent mixture of acetonitrile and 0.1 M ammonium acetate buffer (pH 5) as mobile phase. The flow rate of the mobile phase was 1.5 mL/min and all the detections were carried out at 240 nm using UV detector. The method was linear in the concentration range of 1-200 µg/mL for rosuvastatin with 0.996 coefficient of determination value. For amlodipine, linearity was in the range of 0.5-100 µg/ml with 0.994 coefficient of determination value. Both the drugs along with their degradation products were separated in less than twenty minutes. The results of within-day and between-day precision were varied from 0.72 to 1.81% for rosuvastatin and 0.83 to 1.88% for amlodipine. The results show that this ICH validated method can be employed successfully for the routine as well as stability quantification of both the active ingredients simultaneously in pharmaceutical formulations.

Utilizou-se abordagem de viabilidade custo-efetividade e isocrática, baseada em CLAE, empregando coluna C-18 (250 mm x 4,6 mm, 5 µm) para separar e avaliar os fármacos, rosuvastatina, anlodipino e seus produtos de degradação induzida por estresse, simultaneamente, em formulações farmacêuticas. Focada nos parâmetros das diretrizes da ICH, a separação eficiente de ambos os fármacos e de seus produtos de degradação foi obtida por meio da otimização da fase móvel com mistura de solventes 30:70 (v/v), respectivamente, acetonitrila e tampão acetato de amônio O,1 M (pH 5). A velocidade de fluxo da fase móvel foi de 1,5 mL/min e todas as detecções foram realizadas em 240 nm, utilizando detector de UV. O método foi linear no intervalo de concentração de 1-200 µg/mL para a rosuvastatina com coeficiente de determinação 0,996. Para o anlodipino, a linearidade ficou na faixa de 0.5-100 µg/mL, com coeficiente de determinação 0,994. Ambos os fármacos, junto com seus produtos de degradação, foram separados em menos de vinte minutos. Os resultados de precisão intra-dia e inter-dia variaram de 0,72 a 1,81% para a rosuvastatina e de 0,83 a 1,88%, para o anlodipino. Os resultados mostram que este método validado pelo ICH pode ser empregado com sucesso tanto para a rotina quanto para a quantificação simultânea da estabilidade de ambos os ingredientes ativos em formulações farmacêuticas.

Determination of 1-Deoxynojirimycin in Mulberry Resources by HPLC / 中国药房

OBJECTIVE:To establish a quantitative analysis method to determine the contents of 1-deoxynojirimycin in mulberry resources such as Morus alba,Excrementum bombycis,Folium mori.METHODS:1-deoxynojirimycin in mulberry resources were determined by RP-HPLC method and UV detector on Hypersil C18(250 mm?4.6 mm,5 ?m)column, using acetonitrile-0.1% glacial acetic acid(50 ∶ 50)as moble phase. The flow rate was 1.0 mL?min-1 and the detection wavelength were set at 265 nm with column temperature at 35 ℃. RESULTS:The linear range of 1-deoxynojirimycin were from 5.0?10-4 mg?mL-1 to 1.0?10-3 mg?mL-1 (r=0.999 9)with recoveries of 97.7%(RSD=2.0%,n=6).CONCLUSION:The method is simple, accurate and reproducible for the quality control of Mulberry resources.