Design of Experiment (DOE) Utilization to Develop a Simple and Robust Reversed-Phase HPLC Technique for Related Substances’ Estimation of Omeprazole Formulations

A simple, fast, and sensitive reversed-phase HPLC method with UV detection was developed for the quantitation of omeprazole and its eleven related compounds (impurities) in pharmaceutical formulation using the Thermo Accucore C–18 (50 mm × 4.6 mm, 2.6 μm) column. The separation among all the compounds was achieved with a flow rate of 0.8 mL min⁻¹ employing a gradient program of mobile phase A [0.08 M glycine buffer pH 9.0: acetonitrile; 95:05 (v/v)] and mobile phase B [acetonitrile: methanol; 65:35 (v/v)]. The chromatographic detection was carried out at a wavelength of 305 nm. The method was validated for specificity, linearity, and recovery. The huskiness of the method was determined prior to validation using the Design of Experiments (DOE). The ANOVA analysis of DOE with a 95% confidence interval (CI) confirmed the buffer pH of mobile phase A (p <0.0001) and column temperature (p<0.0001) as significant Critical Method Parameters (CMPs).     

UPLC法同时测定金欣口服液中8种指标成分

目的 建立UPLC法同时测定金欣口服液中芥子碱硫氰酸盐、虎杖苷、野黄芩苷、白藜芦醇、黄芩苷、大黄素-8-O-β-葡萄糖苷、黄芩素、汉黄芩素8种指标成分的量。方法 采用UPLC法,Acquity UPLC BEH C₁₈色谱柱（100 mm×2.1 mm,1.7 μm）,乙腈-0.1%甲酸水溶液为流动相,体积流量0.4 mL/min,梯度洗脱,检测波长280 nm,柱温35 ℃;分别对线性关系、精密度、重复性、稳定性及加样回收率进行考察。结果 被测定的8种指标成分分别在选定的范围内线性关系良好,平均加样回收率99%～102%,RSD均小于3.1%。结论 本方法操作简便,测定结果准确可靠,可用于金欣口服液的质量控制。     

Pharmacokinetics and analgesic effect of ketorolac floating delivery system

Abstract

Objectives: The efficacy of ketorolac tromethamine (KT) floating alginate beads as a drug delivery system for better control of KT release was investigated. The formulation with the highest drug loading, entrapment efficiency, swelling, buoyancy, and in vitro release would be selected for further in vivo analgesic effect in the mice and pharmacokinetics study in rats compared to the tablet dosage form.

Methods: KT floating alginate beads were prepared by extrusion congealing technique. KT in plasma samples was analyzed using a UPLC MS/MS assay.

Results: The percentage yield, drug loading and encapsulation efficiency were increased proportionally with the hydroxypropylmethyl cellulose (HPMC) polymer amount in the KT floating beads. A reverse relationship was observed between HPMC amount in the beads and the KT in vitro release rate. F3-floating beads were selected, due to its better in vitro results (continued floating for >8?h) than others. A longer analgesic effect was observed for F3 in fed mice as compared to the tablets. After F3 administration to rats, the C_max (2.2?±?0.3?µg/ml) was achieved at ～2?h and the decline in KT concentration was slower. F3 showed a significant increase in the AUC (1.89 fold) in rats as compared to the tablets.

Conclusion: KT was successfully formulated as floating beads with prolonged in vitro release extended to a better in vivo characteristic with higher bioavailability in rats. KT in floating beads shows a superior analgesic effect over tablets, especially in fed mice.     

Content uniformity testing: suitability of different approaches for marketed low dose tablets

Context: Content uniformity (CU) testing was developed and improved to control the effectiveness and safety of dosage units. Many modifications of compendial CU test have been introduced and several alternatives have been suggested.

Objectives: This study aims to evaluate the degree of suitability of current USP CU test for low dose tablets and to compare the performance of the current test with that of the former USP27-NF22 and other alternatives for different sample sizes.

Methods: All locally marketed risperidone (RSP) tablets were analyzed using newly developed and validated isocratic UPLC method. The CU results were statistically analyzed in groups with sample sizes comparable to the USP sampling plans.

Results: Seven out of eleven products failed the different requirements of the former and current USP <905>chapters as well as of several alternative CU tests with several substantial deviations.

Conclusion: The current USP <905> chapter was found to have some deficiencies that allowed such failed products to exist in the market. The dependence of compendial CU test on two-staged sampling plan and the use of arithmetic mean to calculate the reference and acceptance values were obvious shortcomings.     

UPLC法检测染料木黄酮在Caco-2单细胞层模型上的吸收特征

目的 研究染料木黄酮在Caco-2单细胞层模型上的吸收特征。方法 将染料木黄酮的细胞样品经高速离心后取上清液,以乙腈-醋酸铵水溶液为流动相,以睾丸酮为内标,采用超高效液相色谱（ultra performance liquid chromatography,UPLC）法检测。考察时间、pH值等因素对染料木黄酮吸收的影响,测定透过Caco-2单细胞层的染料木黄酮浓度并计算其表观渗透系数（P_app）。结果 Caco-2细胞对染料木黄酮的吸收在1 h内呈线性,药物摄取时间定为1 h;pH值对染料木黄酮的吸收没有显著影响。染料木黄酮的线性范围为0.625～40 μmol/L,日间、日内精密度均小于15%。P_app从基顶侧（apical,AP）到基底侧（basolateral,BL）为1.51×10^?5 cm/s,从BL侧到AP侧为1.84×10^?5 cm/s,其渗透系数P_app（BL-AP）/P_app（AP-BL）为1.22。结论 染料木黄酮在肠道的吸收主要以被动扩散为主,UPLC检测方法简单、灵敏度高,可用于研究染料木黄酮在Caco-2单细胞层模型上的吸收特征。     

Effect of Morin on pharmacokinetics of Piracetam in rats,in vitro enzyme kinetics and metabolic stability assay using rapid UPLC method

The aim of this study was to investigate the effect of Morin on the pharmacokinetics of Piracetam in rats, in vitro enzyme kinetics and metabolic stability (high throughput) studies using human liver microsomes in UPLC. For pharmacokinetics studies, male Wistar rats were pretreated with Morin (10 mg/kg) for one week and on the last day, a single dose of Piracetam (50 mg/kg) was given orally. In another group, both Morin and Piracetam were co‐administered to evaluate the acute effect of Morin on Piracetam. The control group received oral distilled water for one week and administered with Piracetam on the last day. As Morin is an inhibitor of P‐ Glycoprotein (P‐gp) and CYP 3A, it was anticipated to improve the bioavailability of Piracetam. Amazingly, relative to control, the areas under the concentration time curve and peak plasma concentration of Piracetam were 1.50‐ and 1.45‐fold, respectively, greater in the Morin‐pretreated group. However, co‐administration of Morin had no significant effect on these parameters. Apart from the aforementioned merits, the results of this study are further confirmed by clinical trials; Piracetam dosages should be adjusted to avoid potential drug interaction when Piracetam is used clinically in combination with Morin and Morin‐containing dietary supplements. The in vitro enzyme kinetics were performed to determined km, V_max & CL_ins. The in vitro metabolic stability executed for the estimation of metabolic rate constant and half‐life of Piracetam. These studies also extrapolate to in vivo intrinsic hepatic clearance (Cl_{int, in vivo}) from in vitro intrinsic hepatic clearance (CL_{int, in vitro})_. Copyright © 2012 John Wiley & Sons, Ltd.     

UPLC-Q-trap-MS鉴定白头翁皂苷D在大鼠离体肠道菌群中的代谢产物

目的 鉴定白头翁皂苷D在大鼠离体肠道菌群体外代谢产物。方法 运用超高效液相色谱-三重四级杆线性离子肼复合质谱（UPLC-Q-trap-MS）分析白头翁皂苷D体外肠道菌群孵育样品,采用Analyst 1.5软件进行数据处理,根据保留时间和各色谱峰质谱裂解规律,比较确定白头翁皂苷D在体外肠道菌群中代谢产物,同时根据质谱二级裂解规律对代谢产物结构进行推测。结果 在大鼠离体肠道菌群孵育样品中鉴定了白头翁皂苷D（M0）原型及常春藤皂苷元3-O-α-L-吡喃鼠李糖-(1→2)-α-L-吡喃阿拉伯糖苷（M1）、常春藤皂苷元3-O-β-D-吡喃葡萄糖-(1→4)-α-L-吡喃阿拉伯糖苷（M2）、常春藤皂苷元（M3）、白头翁皂苷D羟基化（M4）、白头翁皂苷D甲基化产物（M5、M6）、白头翁皂苷D脱氢产物（M7）等7个代谢产物。结论 白头翁皂苷D能够在大鼠离体肠道菌群中发生广泛的代谢。     

The effects of food on the pharmacokinetics of mitiglinide tablets in healthy volunteers and a novel mass-spectrometric (UPLC-MS/MS) method for such studies

What is known and Objective: Mitiglinide (MGN) is a new insulinotropic agent of the glinide class with rapid onset. The effects of food intake on the pharmacokinetic (PK) profile of mitiglinide tablets after single oral administration have not yet been reported in healthy adults. We aimed to assess the effects of food intake on the PK properties of mitiglinide (MGN) tablets, using a novel analytical method, after single escalating oral doses in healthy Chinese volunteers. Methods: In this open‐label, randomized, single‐dose (three distinct doses), two‐way crossover PK study, three doses of MGN 5, 10 or 20 mg were administered to healthy adult volunteers after an overnight fast (fasted condition) or low‐fat breakfast (fed condition) (period 1). After 7 days, the participants received the same dose under the opposite fed/fasted condition (period 2). Serial blood samples were obtained before and through 8 h after study drug administration. Concentrations of MGN in plasma were determined using UPLC‐MS/MS. Adverse events (AEs) were monitored and recorded on each in‐clinic day. Results and Discussion: Twenty‐four Chinese volunteers (eight [four men, four women] volunteers per group) were enrolled in the study. The extent of absorption of MGN was similar in both fed and fasted conditions at single doses in the range 5–20 mg. Food intake was associated with decreases in C_max by 60·4% to 65·2% in the three dose groups and greatly delayed T_max [0·36(Standard deviation 0·16) vs. 1·75(0·92) hours with 5 mg, 0·29(0·19) vs. 1·97(0·81) hours with 10 mg and 0·30(0·10) vs. 1·18(0·68) hours with 20 mg; all, P < 0·05]. t_1/2, CL/F and V/F (P > 0·05) were unaffected. MRT_0–8 at the 5 and 10‐mg doses, but not at the 20‐mg dose, were markedly lower in fasted volunteers than fed volunteers (P < 0·05). What is new and Conclusions: Using a novel UPLC‐MS/MS method, we showed that food intake affected the rate but not the extent of absorption of MGN within the 5‐ to 20‐mg dose range. Gender did not appear to affect the PK properties of MGN in either fasted or fed states. MGN should be preferably taken before food.     

Comparative pharmacokinetics and tissue distribution of cryptotanshinone,tanshinone IIA,dihydrotanshinone I,and tanshinone I after oral administration of pure tanshinones and liposoluble extract of Salvia miltiorrhiza to rats

Salvia miltiorrhiza is one of the most commonly used traditional Chinese medicines in the treatment of cardiovascular and cerebrovascular diseases. Cryptotanshinone (CTS), tanshinone IIA (Tan IIA), dihydrotanshinone I (diTan I), and tanshinone I (Tan I) are the main active compounds in the liposoluble extract of Salvia miltiorrhiza. The differences in the pharmacokinetic and tissue distribution behaviors of the four tanshinones after oral administration of the liposoluble extract of Salvia miltiorrhiza and pure compounds are not clear. This study aims to compare the pharmacokinetics and tissue distribution of the four tanshinones after oral administration of pure tanshinone monomers and the liposoluble extract of Salvia miltiorrhiza. An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) analysis method was developed for the determination of the four tanshinones. The results showed that the AUC and C_max of tanshinones in rats receiving the extract of Salvia miltiorrhiza were significantly increased compared with those receiving the pure tanshinones. In the tissue distribution experiments, the AUC of the four tanshinones in the extract was much greater than the AUC of the monomers in the lung, heart, kidney, liver, and brain, and the coexisting constituents particularly promoted the distribution of tanshinones into tissues that the drug cannot sufficiently penetrate. These findings suggested that the coexisting constituents in the liposoluble extract of Salvia miltiorrhiza play an important role in the alteration of plasma concentration and tissue distribution of the four tanshinones. Understanding these differences could be of significance for the development and application of Salvia miltiorrhiza extract and tanshinone components.     

青霉素杂质谱分析方法的优化与转换

目的建立青霉素杂质谱HPLC分析方法,并将其转换成UPLC/UHPLC方法。方法以青霉素混合降解溶液为样品;首先分析《中国药典》(2010年版,ChP2010)方法甲醇-缓冲盐二元流动相色谱系统的缺陷;再利用实验设计理念,以响应曲面法(response surface methodology,RSM)的中心组合设计(central composition design,CCD)对色谱系统进行优化,满意度函数法确定最优色谱条件,并优化梯度洗脱条件;最后,利用软件对HPLC方法的流速、进样体积和梯度时间进行几何缩放,并通过色谱柱的选择,将其分别转换为UPLC方法和UHPLC方法。结果新HPLC方法:色谱柱为Capcell Pak C18 MGII(4.6mm×250mm,5μm),流速:1.0m L/min,进样体积:20μL;UPLC方法:色谱柱为Cortecs C18(2.1mm×100mm,1.6μm),流速:0.35m L/min,进样体积:2.0μL;UHPLC方法:Cortecs C18(4.6mm×150mm,2.76μm),流速:0.8mL/min,进样体积:10μL。3种方法的检测波长均为225nm,柱温均为34℃;流动相A均为磷酸盐缓冲液(取磷酸二氢钾10.6g,加水至1000mL,用磷酸调pH至3.4)-甲醇(72:14,V/V),流动相B均为乙腈;均为梯度洗脱,但梯度洗脱表不同。结论 3个色谱系统的分离效果(出峰顺序和个数)相似。新HPLC方法可以分离出更多的降解杂质,并明显改善了青霉素峰的拖尾,缩短了分析时间。