Annali di ChimicaVolume 95, Issue 9-10 p. 709-713 Short Communication Precolumn Derivatization Liquid Chromatography with Mass Spectrometry Assay for the Determination of Glucosamine in Small Volume Human Plasma Yunqiu Yu, Yunqiu Yu School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorLei Cai, Lei Cai School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorMing Zuo, Ming Zuo School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorGengli Duan, Corresponding Author Gengli Duan [email protected] School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSchool of Pharmacy, Fudan University, 200032 Shanghai, China, Tel: (++86)-21-54237208Search for more papers by this author Yunqiu Yu, Yunqiu Yu School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorLei Cai, Lei Cai School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorMing Zuo, Ming Zuo School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSearch for more papers by this authorGengli Duan, Corresponding Author Gengli Duan [email protected] School of Pharmacy, Fudan University, 200032 Shanghai, ChinaSchool of Pharmacy, Fudan University, 200032 Shanghai, China, Tel: (++86)-21-54237208Search for more papers by this author First published: 05 September 2005 https://doi.org/10.1002/adic.200590082Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat REFERENCES 1 D. Hamerman, N.Engl.J.Med., 320, 1322 (1989). 2 L. Rodén, Ark. Kemi., 10, 345 (1956). 3 I. Setnikar, Tissue React., 14, 253 (1992). 4 Y. Vidal, R.R. Plana, D.B izzarri, A.L. Rovati, Pharmacol Res Commun., 10, 557 (1978). 5 C. Bassleer, Y. Henrotin, P. Franchimont, Int J Tissue React, 14, 231 (1992). 6 I. Setnikar, R. Cereda, M. A. Pacini, L. Revel, Arzneimittelforschung 41 157 (1991). 7 K.W. Wayne, K.G. Gibson, A.G. Breite, Liq. Chromatogr & Rel Technol., 23, 2861 (2000). 8 X. Zhang, W. Amelung, Soil Biol. Biochem, 28, 1201 (1996). 9 W.F. Osswald, J. Jehle, J. Firl, Plant physiol., 145, 393 (1995). 10 S.R. Hagen, J. chromatrogr., 632, 63 (1993). 11 F. Altman, Anal Biochem., 204, 215 (1992). 12 J. Diaz, J.L. Lliberia, L. Comellas, J. Chromatogr A., 719, 171 (1996). 13 I. Sentikar, C. Giacchetti, G. Zalono, Arznim-forsch., 36, 729 (1986). 14 I. Setnikar, R. Palumbo, S. Canali, G. Zanolo, Arznim-forsch., 43, 1109 (1993). 15 Z.M. Liang, J. Leslie, A. Adebowale, M. Ashraf, N.D. Eddington, J. Pharm. Biomed Anal., 20807 (1999). Citing Literature Volume95, Issue9-10September 2005Pages 709-713 ReferencesRelatedInformation

In this paper, p-toluenesulfonyl isocyanate has been reported as a novel derivatization reagent with strong nuclephilic reactivity for the hydroxyl compounds. The derivatization for the two pharmacologically active 3-hydroxyl metabolites, 3α-hydroxyl-7-methyl-norethynodrel and 3β-hydroxyl-7-methyl-norethynodrel by p-toluenesulfonyl isocyanate can be accomplished in 2min under room temperature. The offline derivatization procedure introduced an easily ionizable sulfonylcarbamic ester moiety to the metabolites. This greatly improved the analyte's sensitivity in negative electrospray ionization and enabled us to achieve the desired lower limit of quantitation at 100pg/ml in plasma. Therefore, a sensitive high performance liquid chromatography-mass spectrometry (HPLC–MS) method for the analysis of the two stereo isomers was developed. The method had been validated to be accurate, precise, and sensitive, and can be used for the metabolism pharmacokinetic study of tibolone in human subjects.

Aim: To investigate the stereoselectivity in human metabolic 3-reduction of tibolone. Methods: Twenty healthy Chinese female volunteers were given a single oral dose of tibolone (2.5 mg), and serial blood samples were collected after treatment. The plasma concentrations of the two pharmacologically active 3-hydroxyl metabolites of tibolone, 3α-hydroxyl-7-methyl- norethynodrel (3α-HMN) and 3β-hydroxyl-7-methyl-norethynodrel (3β-HMN) in plasma were determined by using a validated liquid chromatography-mass spectrometry (LC-MS) method. Results: The apparent elimination half-life ( T ½ ) of 3α-HMN was 1.43±0.52 h, and that of 3β-HMN was 1.53±0.60 h. Maximum plasma concentrations ( C max ) were found to be 8.75±4.36 μg/L for 3α-HMN and 3.59±1.81 μg/L for 3β-HMN. Areas under the plasma concentration versus time curve (AUC 0-t ) were 26.30±12.14 μg·h −1 ·L −1 for 3α-HMN and 9.89±4.93 μg·h −1 · L −1 for 3β-HMN. Conclusion: Stereo-selective differences exist in the pharmacokinetics of tibolone metabolism in humans.

A simple and reliable RP-HPLC method has been developed for the simultaneous determination of ropivacaine and antipyrine in perfusate samples. Samples were analyzed on an ODS column with UV detection at 210 nm after liquid-liquid extraction. The mobile phase consisted of potassium dihydrogenphosphate (25 mM, adjusted to pH 5.0 with phosphoric acid)-acetonitrile (79:21, v/v). The method has been validated to be precise, accurate and linear. It has been applied to the investigation of placental transfer of ropivacaine via a dually perfused cotyledon model of human placenta in vitro.

AIM: To establish reverse phase high performance liquid chromatography (RP-HPLC) method to determine the concentration of ropivacaine and bupivacaine in maternal and fetus plasma. METHODS: Agilent HPLC instrument was used with the column: Dikma-C 18(5 μm,4.6×150 mm). Internal standard was rosiglitazone. The mobile phase was composed of NaH 2PO 4(10 mmol·L -1,pH 3.0)∶CH 3CN(78∶22,V/V).Flow rate was 1.0 mL·min -1.Detection wavelength was 210 nm. RESULTS: The linear coefficient relation of ropivacacine and bupivacaine were Y=0.0295X- 0.0298 and Y=0.0287X+0.0271(r=0.9998,n=7). The minimum detection limit of ropivacaine and bupivacaine were both 0.01 mg·L -1. The linear ranges were both (0.01-5.0) mg·L -1. The average recovery rates of method were 99.82% and 101.01%. The coefficient variations of intra- and inter-day of ropivacaine for 0.1, 1, 5 mg·L -1 were less than 2.47% and 3.75%. The coefficient variations of intra- and inter-day of bupivacaine for 0.1, 1, 5 mg·L -1 were less than 2.69% and 4.75%. The concentration of sixty samples of ropivacaine was 0.15-0.7 mg·L -1, and that of bupivacaine was 0.1-0.58 mg·L -1. CONCLUSION: The RP-HPLC method is simple, sensitive and accurate. It is applicable to determine the concentration of ropivacaine and bupivacaine.

AIM:To establish an assay method for the determination of d timolol, its related substances and enantiomer purity. METHODS: HPLC method was used to determine timolol and its related substances on a Diamonsil TM C 18 column, while enantiomer impurity was inspected on a Cyclobond I 2000 TM column. RESULTS: Perfect resolution had been achieved among timolol, its related substances and degradated products. The assay of timolol showed good linearity over the concentration range of 0 500 mg·L -1 , and its inter day and intra day RSD were all less than 0.6 %. The resolution of the two enantiomers was greater than 2.4. CONCLUSION:The method is simple and accurate to control the quality of d timolol.

目的:研究并建立地塞米松片溶出度的介质及测定方法.方法:采用转篮法分别以1%盐酸,5%乙醇溶液,10%乙醇溶液,15%乙醇溶液及磷酸盐缓冲液(pH=6.6)5种溶出介质进行地塞米松片的溶出试验,以HPLC法测定溶出介质中地塞米松的浓度.结果:研制片与市售地塞米松片在5%乙醇溶液中45 min时的溶出度均大于标示量的79%.结论:所建立的HPLC方法准确、可靠;地塞米松片在5%乙醇溶液中的溶出度符合药典要求.

A rapid, sensitive and accurate capillary gas chromatographic assay with (63)Ni electron capture detection was developed for the determination of anastrozole in human plasma. It comprises a one-step liquid-liquid extraction procedure and gas chromatography on a capillary column using constant oven temperature. This method has been applied to the oral pharmacokinetic study of anastrozole in healthy Chinese male volunteers. Pharmacokinetic parameters of two anastrozole preparations were evaluated after single, oral administrations to 18 subjects at a dose of 1 mg in a single-blind cross-over trial. Plasma anastrozole concentration-time profiles were best described by a two-compartment model. After oral administrations of imported and domestic anastrozole tablets, the t(max) and C(max) were 1.52 +/- 1.04 h and 8.75 +/- 3.03 ng/mL for the former, and 1.43 +/- 1.12 h and 9.44 +/- 3.59 ng/mL for the latter; the elimination half-life was 46.0 +/- 25.2 h vs 41.2 +/- 8.8 h, and the area under the curve (AUC) was 423 +/- 114 ng h/mL vs 444 +/- 157 ng h/mL. The result indicates that the two products are bioequivalent.

目的:建立测定奥美拉唑血药浓度的反相高效液相色谱法,并测定奥美拉唑肠溶胶囊的人体相对生物利用度.方法:色谱柱:Dikma Diamonsil C18(150 mm×4.6 mm, 5 μm);流动相:醋酸铵缓冲液(0.1 mol*L-1,pH 7.0)-乙腈-甲醇(60∶35∶5, v/v);流速:1.2 ml*min-1;检测波长:UV302 nm.以内标法定量,内标物为对羟基苯甲酸乙酯.进行人体随机交叉自身对照试验,血样以二氯甲烷一次提取,测定奥美拉唑肠溶胶囊的相对生物利用度.结果:血药浓度测定的线性范围为0.004～5.0 μg*ml-1,回归方程为Y=3.0218C-0.0079(r=0.9998,n=7),最低检测浓度为2.5 ng*ml-1(S/N=3).平均方法回收率为102.60%,日内、日间精密度均小于5%.结论:方法简便,准确,灵敏,可用于奥美拉唑血药浓度的测定.两种制剂具有生物等效性,试验胶囊的相对生物利用度为(100.4±13.8)%.

奥美拉唑是一种苯并咪唑类质子泵抑制剂,对组胺、胃泌素、乙酰胆碱、食物及刺激迷走神经等引起的胃酸分泌有强而持久的抑制作用,在治疗消化道溃疡方面,比H2受体拮抗剂如西咪替丁和雷尼替丁效果更佳,具有疗程短、迅速缓解疼痛、病变愈合率高的优点.奥美拉唑作用机制称"前药循环",因为它本身是无活性的前药,口服后迅速吸收,能选择性分布于胃壁细胞的胞膜和微管囊泡上的低pH环境中,经H+催化重排为活性物质,因而代谢产物较多,如奥美拉唑砜、5-OH奥美拉唑等,对测定血浆中奥美拉唑浓度有较多干扰.作者建立了以对羟基苯甲酸乙酯为内标测定奥美拉唑在人血浆中浓度的反相HPLC法.由于口服奥美拉唑后相对生物利用度个体差异很大,因而有必要在进行相对生物利用度试验前对受试者进行筛选[1].

AIM: To evaluate the quality of three marketed isosorbide nitrate intravenous injections. (Isosorbide dinitrate from Zhuhai Schwarz Pharma.,Shandong Qilu Pharma., and isosorbide mononitrate from Shandong Lunan Pharma.) METHODS: HPLC, GC, and freezing point depression methods were used to examine the qualities of three isosorbide nitrate intravenous injections. RESULTS:While few differences existed in the assays of the three brands, there was great difference in osmolarities of three products:the product from Zhuhai Schwarz Pharma.was isotonic (289 mmol·L -1 ), but the other two products were both hyperosmotic (2000 mmol·L -1 ). After analysis by HPLC and GC MS, 1,2 propanediol was found to exist in both injections at concentrations ranged from 23 % to 28 % (kg·L -1 ), and 17 % to 23 % (kg·L -1 ), which led to an abnormal high osmolarity. CONCLUSION:It indicate that all three brands are confirmed with their own product standards, but great difference exists in osmotic pressures of three products, due to 1,2 propanediol containing in two of three products.