Simultaneous determination of tanshinones and polyphenolics in rat plasma by UPLC‐MS/MS and its application to the pharmacokinetic interaction between them

The aim of this study was to investigate the pharmacokinetic interaction between tanshinones and polyphenolics which act as the main bioactive compounds in Saliva miltiorrhiza Bunge (SMB). Thus, a rapid and highly sensitive ultra‐performance liquid chromatography‐tandem mass spectrometry (UPLC‐MS/MS) method was developed and validated to determine the concentrations of Tanshinone IIA (TSIIA), Tanshinone I (TI), Cryptotanshinone (CT), Salvianolic acid B (Sal B), Protocatechuic aldehyde (PAL), Rosmarinic acid (RA), and Danshensu (DSS) in rat plasma. The Sprague–Dawley rats were allocated to three groups which orally administered tanshinones (DST), polyphenolics (DFS), and a mixture of tanshinones and polyphenolics (DTF). These samples were processed by a simple liquid‐liquid extraction (LLE) method with ethyl acetate. Chromatographic separation was achieved on an Acquity BEH C₁₈ column (100 mm × 2. 1 mm, 1.7 µm) with the mobile phase consisting of 0.1% (v/v) formic acid and acetonitrile by gradient elution at a flow rate of 0.4 mL/min. The detection was performed on a triple quadrupole‐tandem mass spectrometer TQ‐MS/MS equipped with negative and positive electrospray ionization (ESI) interface in multiple reaction monitoring (MRM) mode. The statistical analysis was performed by the Student's t‐test with P ≤ 0.05 as the level of significance. The method showed good precision, accuracy, recovery, sensitivity, linearity, and stability. The pharmacokinetic profiles and parameters of these polyphenolics changed when co‐administrated with tanshinones. The tanshinones improved the bioavailability of DSS, accelerated the eliminating rate of RA and Sal B and promoted their distribution in vivo. They also contributed to promoting the biotransformation of Sal B to DSS. The polyphenolics could affect the pharmacokinetic of tanshinones, especially CT and TSIIA. Furthermore, the biotransformation of CT to TSIIA and the bioavailability of TSIIA were both improved. This study may provide useful information to avoid unexpected increase of the plasma drug concentration in the clinical practice. Copyright © 2015 John Wiley & Sons, Ltd.     

Pharmacokinetics and tissue distribution of 8,9-epoxy brevifolin in rats, a hepatoprotective constituent isolated from Phyllanthus simplex Retz by liquid chromatography coupled with mass spectrometry method

8,9-Epoxy brevifolin (EBF) is a novel compound isolated from Phyllanthus simplex Retz (P. simplex) and has been demonstrated to possess a hepatoprotective effect. The purposes of the present study were to examine the in vivo pharmacokinetics and tissue distribution of EBF in rats using a liquid chromatography coupled with mass spectrometry quantitative detection method (LC-MS/MS), with luteolin-7-O-glucoside being employed as an internal standard (IS). The method was validated within the concentration range 20-15 000 ng/ml, and the calibration curves were linear with correlation coefficients of >0.999. The limit of quantitation (LOQ) for EBF was 20 ng/ml. The intra-assay accuracy and precision ranged from 98.7% to 100.2% and 2.19% to 6.25%, respectively, while the inter-assay accuracy and precision ranged from 97.5% to 100.3% and 3.35% to 7.28%, respectively. The method was further applied to assess the pharmacokinetics and oral bioavailability of EBF after intravenous and oral administration in rats. The oral bioavailability of EBF was 12.46 +/- 2.31%. In the tissue distribution assay, its concentration was higher in the heart (13.2 +/- 0.24 microg/g) and liver (14.5 +/- 0.19 microg/g) than in other tissues.     

Hydrogen atom abstraction of 3,5-disubstituted analogues of paracetamol by horseradish peroxidase and cytochrome P450

1. The formation of free radicals during enzyme catalysed oxidation of eight 3,5- disubstituted analogues of paracetamol (PAR) has been studied. A simple peroxidase system as well as cytochrome P450-containing systems were used. Radicals were detected by electron spin resonance (ESR) onincubationof PAR and 3,5-diCH-,3,5-diC H-,3,5- di t C H-, 3,5-diOCH-, 3,5-diSCH-, 3,5-diF-, 3,5-diCl- and 3,5-diBr-substituted analogues of PAR with horseradish peroxidase in the presence of hydrogen peroxide (H O). Initial analysis of the observed ESR spectra revealed all radical species to be phenoxy radicals, based on the absence of dominant nitrogen hyperfine splittings. No radicalswere detectedinrat livercytochromeP450-containingmicrosomalorreconstituted systems. 2. To rationalize the observed ESR spectra, hydrogen atom abstraction of PAR and four of the 3,5-disubstituted analogues (3,5-diCH-, 3,5-diOCH-, 3,5-diF- and 3,5-diClPAR) was calculated using ab initio calculations, and a singlet oxygen atom was used as the oxidizing species. The calculations indicated that for all compounds studied an initial hydrogen atomabstraction fromthe phenolic hydroxylgroup is favoured by approximately 125 kJ molover an initial hydrogen atom abstraction from the acetylamino nitrogen atom, and that after hydrogen abstraction from the phenolic hydroxyl group, the unpaired electron remains predominantly localised at the phenoxy oxygen atom (85%). 3. The experimental finding of phenoxy radicals in horseradish peroxidase H O incubations paralleled these theoretical findings. The failure to detect experimentally phenoxy radicals in cytochrome P450-catalysed oxidation of any of the eight 3,5- disubstituted PAR analogues is more likely due to the reducing effects that agents like NADPH and protein thiol groups have on phenoxy radicals rather than on the physical instability of the respective substrate radicals.     

氢氯噻嗪在小鼠体内的组织分布及药动学研究

目的建立小鼠血浆及组织中氢氯噻嗪浓度测定的HPLC—MS／MS方法,研究氢氯噻嗪在小鼠体内的组织分布及药动学。方法在血浆样品及组织样品中加入内标布洛芬,分别采用乙醚和乙酸乙酯提取处理,以甲醇-水-氨水（90：10：1）为流动相,用C18柱分离,采用电喷雾电离源（Turbo Ionspray）,负离子方式检测,扫描方式为多反应监测（MRM）。以此方法测定72只雄性健康小鼠给予氢氯噻嗪后10个时间点的血浆及组织样品,并采用DAS2．0药动学程序计算主要药动学参数。结果氢氯噻嗪在血浆中线性范围为5．0～1000μg·L^-1,在组织中线性范围为0．05～50．0μg·g^-1,日内、日间RSD均〈15％。小鼠灌胃给予氢氯噻嗪后快速分布在各组织中,其中胃、肠、肝分布最多,心分布最少。结论本法快速、准确、专属、灵敏。氢氯噻嗪灌胃给药后吸收快,消除半衰期长,组织分布广泛。     

UPLC–MS/MS for the determination of azilsartan in beagle dog plasma and its application in a pharmacokinetics study

The purpose of the study is to develop an ultra performance liquid chromatography-tandem mass spectrometry (UPLC–MS/MS) to determinate the concentration of azilsartan in the dog plasma. After precipitated by methanol, the plasma sample containing azilsartan and diazepam (internal standard, IS) was determined by UPLC–MS/MS. The mobile phase consisted of acetonitrile-water was pumped at a flow rate of 0.3 ml/min in gradient elution. Kinetex 2.6 μ XB-C18 column (50 × 2.1 mm, 100 Å; Phenomenex, USA) were used for LC separations. The column temperature was 30 °C and the injection volume was 5 μl. The electrospray ionization (ESI) and multiple reaction monitoring (MRM) were applied at the transitions of m/z 457 → 279 (azilsartan) and m/z 285 → 193 (diazepam), respectively. The developed method was identified a good linearity over a concentration range of 2.5–5000 ng/ml. The lower limit of quantitation (LLOQ) was 2.5 ng/ml. The intra-day and inter-day precision (relative standard deviation, RSD%) were less than 10% and accuracy (relative error, RE %) was less than 5% at three quality control levels. The extraction recovery of azilsartan at three quality control levels were 82.41 ± 0.68%, 98.66 ± 11.00%, 102.43 ± 0.82%. And the recovery for IS (100 ng/ml) was 91.75 ± 0.54%. A validated UPLC–MS/MS method was firstly developed for the quantification of azilsartan in dog plasma and it was applied to the pharmacokinetics study.     

国产与进口瑞舒伐他汀钙片在健康人体的药代动力学及生物等效性

目的 评价进口与国产瑞舒伐他汀钙片(降血脂药)在健康人体的生物等效性.方法 20例健康成年男性受试者随机分组,按自身对照单次口服瑞舒伐他汀钙片20 mg后,用UPLC-MS-MS法测定瑞舒伐他汀的血浆浓度,非房室模型法计算各主要药代动力学参数,并进行方差分析和生物等效性评价.结果 瑞舒伐他汀片和胶囊的达峰时间tmax分别为(3.35±0.99)和(3.00±1.17)h;达峰浓度Cmax分别为(21.59±15.44)和(16.86±11.03)ng·mL-1;t1/2分别为(11.90±4.34)和(11.27±3.87)h;AUC0-96分别为(173.30±118.18)和(150.58±95.35)ng·h·mL-1;AUC0-∞分别为(175.05±119.02)和(151.88±95.78)ng·h·mL-1.经统计分析,2组间无显著性差异(P＞0.05).结论 国产瑞舒伐他汀钙片(浙江京新药业股份有限公司)与进口瑞舒伐他汀钙片(阿斯利康公司)2种制剂生物等效.     

超高效液相色谱-串联质谱法测定大鼠血浆及组织中贝达喹啉浓度及其药动学考察

目的:建立超高效液相色谱-串联质谱(UPLC-MS/MS)法测定SD大鼠血液及组织中贝达喹啉的浓度,研究其在大鼠体内的药动学及组织分布.方法:采用UPLC-MS/MS联用技术,测定大鼠血液及组织中贝达喹啉的药物浓度,并利用DAS软件及非房室模型统计矩方法计算药动学参数.结果:贝达喹啉线性范围为0.1～500 ng·mL...     

Pharmacokinetics behaviors of l-menthol after inhalation and intravenous injection in rats and its inhibition effects on CYP450 enzymes in rat liver microsomes

Abstract

1. l-Menthol, as a kind of monocyclic terpene, is widely used in inhalation formulations, food and tobacco. The purpose of this study was to investigate the pharmacokinetic behavior of l-menthol as well as its influence on the activities of cytochrome P450 enzymes.

2. The pharmacokinetic behaviors of l-menthol after inhalation (50?mg/kg) and intravenous injection (10?mg/kg) were investigated. A rat liver microsomal model was adopted to elucidate the inhibitory effect of l-menthol on CYP1A2, CYP2C11, CYP2D1/2, CYP2D4, CYP2E1 and CYP3A1 using phenacetin, tolbutamide, omeprazole, dextromethorphan, chlorzoxazone and testosterone as probe drugs, respectively.

3. The plasma concentration reached the C_max within 1.0?h (inhalation) and descended with the T_1/2 of 8.53 and 6.69?h for inhalation and i.v. administration, respectively. IC₅₀ for inhibition of l-menthol on CYP 450 enzymes were 4.35?μM for 2D4, 8.67?μM for 1A2, 13.02?μM for 3A1, 14.78?μM for 2D1/2, 234.9?μM for 2C11 and 525.4?μM for 2E1, respectively.

4. The results illustrate the pharmacokinetic process of l-menthol in rats and provide information for further rational applications. l-Menthol had moderate inhibitions on CYP2D4 and 1A2, which might affect the disposition of medicines primarily dependent on these pathways.     

乌苯美司胶囊人体药代动力学和生物等效性试验

目的:采用HPLC-MS/MS法研究乌苯美司胶囊在人体的药代动力学,并评价生物等效性。方法:24例健康男性受试者单次交叉口服30 mg乌苯美司胶囊受试制剂和参比制剂,测定给药后不同时间点血浆中乌苯美司经时血药浓度,采用DAS 2.0软件进行药代动力学参数计算和生物等效性评价。结果:受试者单次口服试验制剂与参比制剂后,达峰时间分别为(0.72±0.28)和(0.80±0.15)h;峰浓度分别为(2 416.83±379.56)和(2 291.57±418.92)μg.L-1;AUC0～t分别为(3 950.66±589.84)和(4 012.93±521.49)μg.L-1.h;AUC0～∞分别为(3 957.04±590.19)和(4 016.23±520.60)μg.L-1.h;t1/2分别为(3.49±1.91)和(2.80±1.51)h。试验制剂与参比制剂的生物等效性为98.0%(94.2%～101.9%)。结论:乌苯美司胶囊试验制剂与参比制剂生物等效。     

Pharmacokinetics and tissue distribution study of novel potent antiplatelet agent S007-867 in mice using HPLC-MS/MS

Abstract

1.?S007-867 is a novel antiplatelet agent that shows promising in vitro and in vivo efficacy. For further development and better pharmacological elucidation, we characterized pharmacokinetics and tissue distribution of S007-867 in a mouse model.

2.?A sensitive, selective and robust LC-MS/MS method was developed and validated in the mouse plasma and tissue for quantification of S007-867. The chromatographic separation was performed on Waters Symmetry Shield C18 column (150?×?4.6?mm, 5?µm) using methanol and ammonium acetate buffer.

3.?S007-867 was rapidly absorbed and distributed to various tissues. Following single oral administration of S007-867 in the mouse, the concentration was in the order of C intestine?>?C liver?>?C kidney?>?C heart?>?C spleen?>?C lungs?>?C brain. Tissue to plasma area under the plasma curve ratio suggested that the maximum amount of drug was found in the intestine and liver. Half life of S007-867 was found longer in the heart (8.08?h), spleen (～?7.94?h) and kidney (～?15.41?h) as compared with other tissues.

4.?The preclinical pharmacokinetics and tissue distribution data obtained using this LC-MS/MS method are expected to assist the future clinical investigations of S007-867 as a promising antiplatelet agent.     

国产雷米普利胶囊在健康人体的药代动力学和相对生物利用度

目的研究健康受试者口服雷米普利胶囊(抗高血压药)的药代动力学和相对生物利用度。方法20名健康受试者随机服用雷米普利受试和参比制剂各10mg,用HPLC-MS/MS法测定血浆中雷米普利和雷米普利拉的浓度。结果主要药代动力学参数,试验与参比制剂中雷米普利的tmax分别为(0.60±0.17),(0.63±0.25)h;Cmax分别为(40.11±14.48),(41.78±13.18)ng·mL-1;t1/2分别为(2.75±1.36),(2.28±1.28)h;AUC0-12分别为(42.09±11.22),(41.81±12.89)ng·h·mL-1;试验制剂的相对生物利用度为(101.47±16.02)%。试验与参比制剂中雷米普利拉的tmax分别为(2.70±0.47),(2.60±0.60)h;Cmax分别为(42.02±12.53),(41.80±14.65)ng·mL-1;t1/2分别为(17.99±6.28),(18.51±5.81)h;AUC0-72分别为(310.65±91.42),(310.21±102.74)ng·h·mL-1。试验制剂的相对生物利用度为(101.09±15.28)%。结论参比与试验制剂具有生物等效性。     

尿中丹参素的测定及其在人体的药代动力学

目的研究丹参素在人体内的药代动力学。方法用尿药法研究丹参素的人体药代动力学。使用C₁₈小柱对尿样中的丹参素进行净化和富集，再在ODS柱上，以乙腈-0.01 mol·L^-1磷酸二氢钾溶液（pH 2.8）为流动相，在280 nm检测。结果健康志愿者po含丹参素20 mg的复方中药颗粒剂A和丹参水煎剂后，丹参素的消除半衰期t_1/2分别为(0.92±0.16) h和(0.94±0.21) h，8 h内丹参素尿药累积排泄率分别为(6.2±2.8)%和(14±4)%。结论 在正常剂量下，丹参素可由胃肠道吸收入人体，并可以原型从肾脏排泄；服用复方制剂后，丹参素的尿药累积排泄率较单用丹参煎剂显著降低，而二者的消除半衰期无显著差异。     

Rapid determination of isocorydine in rat plasma and tissues using liquid chromatography – tandem mass spectrometry and its applications to pharmacokinetics and tissue distribution

1. A rapid and sensitive method for the determination of isocorydine in rat plasma and tissues was developed using liquid chromatography–tandem mass spectrometry (LC–MS/MS).

2. The biological samples were processed by extracting with diethyl ether–dichloromethane (3:2, v/v) and tetrahydropulmatine was used as the internal standard (IS). Detection of the analytes was achieved using positive ion mode electrospray ionization in the multiple reaction monitoring mode. The MS/MS ion transitions monitored were m/z 342.0→279.0 and 356.0→191.9 for isocorydine and IS, respectively.

3. The maximum plasma concentration (C_max 2496.8?±?374.4 µg/L) was achieved at 0.278?±?0.113?h (T_max) and the half-life (t_1/2) of isocorydine was 0.906?±?0.222?h after a 20?mg/kg oral administration. As for a 2?mg/kg intravenous (i.v.) administration, the C_max and clearance (CL) were 1843.3?±?338.3 µg/L and 2.381?±?0.356?L/h/kg, respectively. Based on the AUC_0–∞ obtained from oral and i.v. administration, the absolute bioavailability (F) was estimated as 33.4%. Tissue distribution results indicated that isocorydine underwent a rapid and wide distribution into tissues and it could effectively cross the blood-brain barrier.

     

液相色谱/质谱联用法测定国产辛伐他汀胶囊人体相对生物利用度

目的:建立辛伐他汀血浆中药物浓度的液质联用测定方法,研究其在人体的药代动力学及生物等效性。方法:18名健康男性受试者随机自身交叉给药,分别口服单剂量国产辛伐他汀胶囊剂和进口片剂20mg。用液相色谱/质谱联用测定血浆中辛伐他汀在人体内的浓度。结果;国产辛伐他汀胶囊剂和进口片剂主要药代动力学参数为:t_(max)分别为2.09±0.41h和2.13±0.47h,C_(max)分别为4.66±2.23μg·L~(-1)和4.71±2.45μg·L~(-1),AUC_(0-t)分别为19.42±3.99μg·h·~(-1)和19.76±4.13μg·h·L~(-1)。国产辛伐他汀胶囊剂的相对生物利用度为(98.3±10.8)％。结论:经统计学分析,国产辛伐他订胶囊剂和进口片剂具有生物等效性。     

罗红霉素胶囊人体药物动力学及生物等效性研究

目的建立人血浆中罗红霉素的HPLC-MS方法,测定其片剂的药物动力学参数及相对生物利用度。方法20名健康受试者随机交叉口服罗红霉素胶囊。血样用乙腈沉淀、离心后进入LC-MS分析系统,色谱柱:Hypersil C18ODS(5μm,25 cm×4.6mm);流动相:10mmol/L醋酸铵缓冲液(pH3.5)-甲醇(15∶85);质谱条件:气动辅助电喷雾离子化,正离子检测,选择性离子检测(SIM),检测离子:罗红霉素m/z837.5[M H] ,克拉霉素m/z748.3[M H] 。结果在0.025~50μg/mL范围内峰比值(罗红霉素峰峰面积As和内标克拉霉素面积A i的比值)与浓度线性关系良好(r=0.999 9),最低定量限为3ng/mL。绝对回收率为85.87%~95.03%。罗红霉素片剂的相对生物利用度为(102.2±26.0)%。结论建立的分析方法灵敏、准确、简便,符合血浆样品的测定要求。受试制剂和参比制剂后,统计学结果表明:两种制剂生物等效。     

红景天苷在比格犬体内绝对生物利用度研究

目的建立比格犬血浆中的红景天苷的HPLC-MS/MS测定方法,研究红景天苷在比格犬体内的绝对生物利用度。方法以天麻素为内标,血浆样品经蛋白沉淀后,经Symmetry RP18(100 mm×4.6 mm,3.5μm)柱分离,使用体积分数0.1%甲酸溶液(A)-含0.1%甲酸和20%乙腈的甲醇溶液(B)作为流动相,进行等度洗脱(35%B),流速为0.4 ml/min,柱温40℃,进样量2μl;通过电喷雾电离源(ESI),以多反应监测(MRM)模式进行负离子检测,红景天苷、天麻素的MRM离子对分别为m/z 299.1→118.9、m/z 285.1→122.9。比格犬分别以口服和静注两种给药方式给予红景天苷原料药,在不同时间点取血,样品采用HPLC-MS/MS法测定,研究红景天苷的药动学及绝对生物利用度。结果红景天苷的质量浓度在10~10000 ng/ml内线性关系良好(r>0.9986),最低定量浓度为10.0 ng/ml。方法回收率为89.5%~91.8%,日内精密度(RSD)<9.7%,日间精密度(RSD)<7.3%。单剂量口服15 mg/kg或静注1.5 mg/kg红景天苷原料药后,cmax分别为(9680±3725)和(9310±1645)ng/ml;tmax分别为(1.25±0.67)和(0.011±0.017)h,AUC0?t分别为(20535.4±5200.0)和(4646.7±720.5)ng·h/ml,AUC0-∞分别为(20607.9±5266.2)和(4691.6±715.2)ng·h/ml;t1/2分别为(1.31±0.63)和(0.98±0.13)h。结论该方法简便快速、灵敏可靠,可用于红景天苷体内过程研究。红景天苷在比格犬体内的绝对生物利用度为(43.9±11.2)%。     

盐酸氨基葡萄糖颗粒在健康人体的药代动力学和相对生物利用度

目的研究盐酸氨基葡萄糖(预防与治疗骨关节炎药)在健康人体内药代动力学和相对生物利用度。方法18名健康男性受试者随机交叉单剂量口服盐酸氨基葡萄糖受试制剂和参比制剂各480 mg,用液相色谱串联质谱法测定给药后不同时间的血药浓度,计算主要药代动力学参数。结果盐酸氨基葡萄糖受试制剂和参比制剂主要药代动力学参数:t_(1/2)分别为(1.57±0.67)、(1.40±0.46)h;t_(max)分别为(2.75±0.43)、(2.86±0.48)h;C_(max)分别为(1.17±0.97)、(1.27±1.07)μg·mL~(-1);AUC_(0→t)分别为(3.28±2.05)、(3.38±1.94)μg·h·mL~(-1);AUC_(0→∞)分别为(3.48±2.06)、(3.56±1.93)μg·h·mL~(-1);受试制剂的相对生物利用度为(101.28±31.92)%。结论2制剂具有生物等效性。     

UPLC–MS/MS assay for quantification of an inhibitor of kinases (Foretinib) in plasma: Application to a pharmacokinetic study in rats

Foretinib, an oral multikinase inhibitor, is known to have anti-tumor effects against cancers. The doses and the levels of foretinib vary based on the type of cancer to be treated. An accurate and precise method is required to determine the level of foretinib and its pharmacokinetics. Here, we developed such a method, which was validated based on the guidelines of the FDA and EMA. Foretinib and ibrutinib (the internal standard (IS)) were extracted using tert-butyl methyl ether. Foretinib and IS were eluted in approximately 1.2 min. Thus, a linear, fast, accurate, and precise method was developed. The calibration curve was linear (r² ˃ 0.997) in the range of 0.5–400.0 ng/mL and the lowest limit of quantitation was 0.5 ng/mL. The average recovery, accuracy, and precision were 87.9%, 88.7%, and ≤7.8%, respectively. The analyte was deemed stable using various stability tests. The validated assay was then fruitfully applied to a pharmacokinetics study in rats, which revealed that foretinib was absorbed and the maximum concentration achieved at 4.0 h after the administration of a single dose of foretinib.     

An LC–MS/MS method for the determination of salidroside and its metabolite p-tyrosol in rat liver tissues

Context: Salidroside and its metabolite p-tyrosol are two major phenols in the genus Rhodiola L. (Crassulaceae). They have been confirmed to possess various pharmacological properties and are used for the prophylaxis and therapeutics of many diseases. Several analytical methods have been developed for the determination of the two compounds in plant materials and biological plasma matrices. However, these methods are not optimal for biological samples containing complex organic interferences, such as liver and brain tissues.

Objective: This study aimed to further develop and validate a simple and specific LC–MS/MS method for the determination of salidroside and its metabolite p-tyrosol in rat liver tissues using paracetamol as the internal standard (IS).

Materials and methods: Salidroside and p-tyrosol with the IS paracetamol and liver tissues were used as model compounds and biological samples. Samples were processed by protein precipitation (PP) with methanol, the supernatant was dried under nitrogen and the residue was reconstituted in a mobile phase that consisted of a mixture of acetonitrile and water (1:9, v/v). Salidroside and p-tyrosol were detected in negative mode under multiple reaction monitoring (MRM) by a triple quadrupole tandem mass spectrometer coupled with electrospray ionization.

Results: Standard curves were linear over the concentration range of 50–2000?ng/mL with correlation coefficients of 0.995 or better for both salidroside and p-tyrosol. The intra- and inter-day accuracy for salidroside ranged between 104.90 and 112.73% with a precision of 3.51–14.27%. For p-tyrosol, the intra- and inter-day accuracy was between 92.38 and 100.59%, and the precision was 8.54% or less. The stability data showed that no significant degradation occurred under the experimental conditions. The recoveries were 111.44, 108.10, and 102.00% for salidroside at concentrations of 50, 500 and 2000?ng/mL, respectively, and were 105.44, 105.50, and 113.04% for tyrosol at concentrations of 50, 500 and 2000?ng/mL, respectively. The matrix effects were 83.85–92.45% for salidroside and 85.61–92.49% for p-tyrosol at three QC levels. This method was successfully applied to a liver tissue distribution study of salidroside and its metabolite p-tyrosol in rats.

Discussion and conclusion: This newly established method is validated as simple, reliable and accurate. It can be used as a valid analytical method for the intrinsic quality control of biological matrices, especially tissue samples.     

土壤水分对新鲜和采后干燥丹参根中活性成分含量的影响

目的：进一步验证丹参药材中丹酚酸类成分尤其是丹酚酸B是采后干燥的产物;了解栽培过程中土壤水分状态对新鲜和阴干后丹参药材中丹酚酸类和丹参酮类成分的影响。方法采用高效液相色谱法测定了不同土壤水分条件栽培的新鲜和采后阴干丹参样品中6种酚酸类和4种丹参酮类成分的含量。结果新鲜丹参样品中,均含有较高含量丹参酮类成分,但只有极度干旱胁迫时（土壤水势＜30％）,才可检测到丹酚酸B（＜1％）,且无其他酚酸类成分。阴干样品中丹酚酸类成分含量均显著增加,其中丹酚酸B含量达4．2％;丹参酮类成分也增加了30％以上。阴干后丹参中丹酚酸B及总酚酸含量与栽培过程中土壤水势呈现显著负相关。结论采后干燥有利于丹参中活性成分积累。丹参药材中丹酚酸类成分尤其是丹酚酸B是栽培和采后极度干旱（干燥）的产物,栽培过程中适度的干旱胁迫有利于药材中酚酸类成分的产生。