Abstract：
:A conventional liquid-liquid extraction (LLE) procedure with high-performance liquid chromatography (HPLC) has been developed for the determination of verapamil and its main metabolite, norverapamil, in plasma. After addition of the internal standard, plasma samples were basified with phosphate buffer (pH 9.0) and extracted with a mixture of cyclohexane-dichloromethane. After centrifugation, the organic layer was separated and the analytes were extracted back into a 0.1 N sulphuric acid solution containing 2-aminoheptane. An aliquot of this aqueous phase was then injected directly onto the HPLC column. This LLE procedure has been compared with an automated liquid-solid extraction (LSE) method that has been developed in parallel. Good linearity was obtained using both extraction methods. The absolute recoveries for the two analytes were ca 95% with the automated LSE procedure and slightly lower (ca 84%) for the LLE method. The automated method gives better results with respect to detectability and precision, but the LLE procedure is simpler to develop, requires much less expensive equipment, and remains a useful alternative when the number of samples to be analysed is limited.
journal_name
J Pharm Biomed Analjournal_title
Journal of pharmaceutical and biomedical analysisauthors
Hubert PH,Chiap P,Ceccato A,Bechet I,Sibenaler-Dechamps R,Maes P,Crommen Jdoi
10.1016/0731-7085(91)80102-fsubject
Has Abstractpub_date
1992-10-01 00:00:00pages
937-42issue
10-12eissn
0731-7085issn
1873-264Xpii
0731-7085(91)80102-Fjournal_volume
10pub_type
杂志文章abstract：:Stroke is the third most common cause of death in most industrialized countries. Polygonum multiflorum (He-Shou-Wu, HSW) is one of the traditional Chinese medicines with multiple pharmacological activities which is widely used in Chinese recipe. This study aims to explore the protective effect of HSW on ischemic strok...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2018.03.049
更新日期：2018-06-05 00:00:00
abstract：:The application of potentiometric biosensors based on membrane ion-selective electrodes for flow injection analysis (FIA) is presented. The biosensors have been obtained by covalent binding of enzyme molecules directly to surface of ion-selective membranes. The biosensor/FIA systems enable the determination of urea an...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(98)00230-1
更新日期：1999-03-01 00:00:00
abstract：:Glimepiride (Amaryl), which is a new oral antidiabetic drug in the sulfonylurea class, was analysed by using second order derivative UV spectrophotometry. The quantification of glimepiride in dimethylformamide was performed in the wavelength range of 245-290 nm at N = 6, ?lambda = 21. The second order derivative spect...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(00)00445-3
更新日期：2001-01-01 00:00:00
abstract：:The performance of ferrate(VI) in treating sulfamethoxazole (SMX), diclofenac (DCF), carbamazepine (CBZ) and bezafibrate (BZF) in test solutions containing the four compounds was investigated. A series of jar-test experiments was performed on a bench-scale at pH 6-9 and at a ferrate(VI) dose of 1-5 mg Fe/L. The result...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2014.06.032
更新日期：2015-03-15 00:00:00
abstract：:A high performance liquid chromatographic method was developed to simultaneously determine the 12 major constituents of Forsythia suspensa, namely R-suspensaside, S-suspensaside, S-suspensaside methyl ether, (+)-pinoresinol-beta-d-glucoside, forsythiaside, (+)-epipinoresinol-4'-O-glucoside, suspensaside A, rutin, phil...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2006.09.033
更新日期：2007-02-19 00:00:00
abstract：:The fully humanized Lewis-Y carbohydrate specific monoclonal antibody (mAb) IGN311 is currently tested in a passive immunotherapy approach in a clinical phase I trail and therefore regulatory requirements demand qualified assays for product analysis. To demonstrate the functionality of its Fc-region, the capacity of I...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2009.01.029
更新日期：2009-05-01 00:00:00
abstract：:This report describes the fabrication and the application of a novel carbon nanotube (CNT)-epoxy composite electrode as a sensitive amperometric detector for the capillary electrophoresis (CE). The composite electrode was fabricated on the basis of the in situ polycondensation of a mixture of CNTs and 1,2-ethanediamin...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2015.07.044
更新日期：2015-11-10 00:00:00
abstract：:The role of selenium as an antioxidant and anticancer agent is very well documented in the literature. Selenium compound showing the highest activity as a free radicals scavenger and as an anticancer agent should contain selenium at +4 oxidation level. The synthesis of selenitetriglycerides (named selol) was carried o...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(03)00205-x
更新日期：2003-08-08 00:00:00
abstract：:Vaccines manufactured following "classical" methods contain inactivated or infectious but attenuated viruses or bacteria. In some instances, the inactivated agents are purified. In other cases, the vaccines contain protein subunits or practically pure polysaccharides. It is generally accepted that the final product ca...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章,评审
doi：10.1016/0731-7085(89)80087-1
更新日期：1989-01-01 00:00:00
abstract：:A high performance thin-layer chromatographic (HPTLC) method for the simultaneous determination of the hypolipidemic agents, E- and Z-isomers of guggulsterone in Commiphora mukul resin, guggulipid (ethyl acetate extract of resin), and its pharmaceutical formulation, was developed. The developed system was efficient en...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2011.05.021
更新日期：2011-09-10 00:00:00
abstract：:The development of a new HPLC-UV diode array procedure applied to follow the hydrolytic degradation of two well-known 4-nitrophenyl-1,4-dihydropyridine derivatives, nitrendipine and nisoldipine is reported. Hydrolysis of each drug were carried out in ethanol/Britton-Robinson buffer at different pHs, stored into amber ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(01)00703-8
更新日期：2002-06-01 00:00:00
abstract：:The pharmacokinetics and pharmacodynamics (PK/PD) of imidaprilat, an active metabolite of imidapril, a new angiotensin-converting enzyme (ACE) inhibitor, were investigated. Imidapril was infused subcutaneously for 4 weeks via an osmotic pump implanted under the skin in the back of male spontaneously hypertensive rats ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(96)02015-8
更新日期：1997-08-01 00:00:00
abstract：:Unfractioned Heparins (UFH) and Low Molecular Weight Heparins (LMWHs) are non-chromophoric, high charged sulphated molecules which are difficult to elute and detect with conventional liquid chromatography methods. Moreover, the detection of LMWHs at low concentration level, like in samples coming from dissolution test...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2008.04.009
更新日期：2008-09-29 00:00:00
abstract：:A rapid and sensitive method for determination of ascaridole in rat plasma was developed based on gas chromatography-mass spectrometry (GC/MS). The analyte and internal standard (IS), naphthalene, were extracted from plasma with ethyl acetate and then separated by GC on a HP-5MS capillary analytical column (30 m x 0.2...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2008.06.017
更新日期：2008-11-04 00:00:00
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journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2012.01.019
更新日期：2012-04-07 00:00:00
abstract：:The new approach to drug development, especially for cardiovascular and brain diseases, brought to synthesis of new lipophillic derivatives of strong calcium chelator BAPTA - DP-b99 and DP-109. Due to their chelating ability, these compounds require metal-free stationary phases, and their high hydrophobicity resulted ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(00)00567-7
更新日期：2001-03-01 00:00:00
abstract：:Daphne genkwa Sieb. et Zucc., as a traditional oriental herb, has been widely distributed and employed in China. The major bioactive components in D. genkwa are flavonoid compounds, which showed pharmacological activities such as anti-inflammatory, analgesic, anti-tumor and immunomodulatory activities. In this study, ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2019.112856
更新日期：2020-01-05 00:00:00
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journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(03)00251-6
更新日期：2003-08-08 00:00:00
abstract：:An unknown degradation product (DP-1) increased in olmesartan medoxomil (OLM) tablets stored at 40 degrees C/75% r.h., reaching 0.72% after 6 months. The molecular weight and fragment information obtained by LC-MS suggested that DP-1 was a dehydrated dimer of olmesartan (OL) and the presence of ester carbonyl group wa...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2008.02.021
更新日期：2008-07-15 00:00:00
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journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章,随机对照试验
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journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
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更新日期：2019-09-10 00:00:00
abstract：:A method is described for the GC-NPD determination of urinary codeine and morphine after derivatization with trifluoroacetic anhydride. The lower limit for accurate quantitative determination was 0.05 microgram ml-1. After the oral administration of Bisolvon Griblettes corresponding to 30 mg codeine phosphate to seven...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(93)80026-w
更新日期：1993-04-01 00:00:00
abstract：:Boldenone (BOLD), an anabolic steroid, is likely to be abused in livestock breeding and in sports. Although some of BOLD metabolites in human urine, such as 5β-adrost-1-en-17β-ol-3-one (BM1), have been detected, investigations on their excretion patterns for both genders are insufficient. Moreover, little research on ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2015.08.014
更新日期：2015-11-10 00:00:00
abstract：:Twenty-seven highly diversified pharmaceutical compounds were used as a test set to evaluate matrix effects from microsomal media on LC/MS analyses. The individual effects of Tris buffer, NADPH and microsomes on ESI response were investigated. Direct flow injection MS/MS analysis, using no sample preparation or HPLC s...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(01)00562-3
更新日期：2002-04-15 00:00:00
abstract：:Antioxidants are added to foods and drugs to inhibit their oxidation. As these additives are somewhat toxic, it is necessary to control the amount added to any food or drug. Liquid chromatography (LC) is a powerful tool for this purpose. Many antioxidants are electroactive molecules which enables the advantages of ele...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(93)80150-y
更新日期：1993-01-01 00:00:00
abstract：:CpG oligodeoxynucleotide 107 (CpG ODN107) could be used as a novel radiosensitizer for glioma. Herein, a novel and sensitive reversed-phase HPLC coupled with electrospray triple quadrupole mass spectrometry (LC-MS/MS) following a one-step C18 solid-phase extraction (SPE) for biological matrix removal was developed and...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2012.06.022
更新日期：2012-11-01 00:00:00
abstract：:In terms of risk assessment especially for the impurities with different ultraviolet (UV) absorptions in 16-membered macrolides produced by fermentation, quantification without the availability of corresponding reference substances currently poses a challenge. In this study, a reliable method was established for the a...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2020.113170
更新日期：2020-05-30 00:00:00
abstract：:MEGATON, a dietary supplement, was analyzed in order to detect PDE-5 inhibitors and their analogues. A new analogue of vardenafil could be detected by high-performance liquid chromatography (HPLC) analysis with a photodiode array detector (PDA). This compound was compared with sildenafil, tadalafil, and vardenafil as ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2010.09.022
更新日期：2011-02-20 00:00:00
abstract：:A simple and rapid spectrophotometric methods have been estimated for the microdetermination of phenylephrine HCl (I) and orphenadrine citrate (II). The proposed methods are based on the formation of ion-pair complexes between the examined drugs with alizarine (Aliz), alizarine red S (ARS), alizarine yellow G (AYG) or...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(02)00437-5
更新日期：2002-11-07 00:00:00
abstract：:The objective of the study was to determine the identity of a new impurity detected in HPLC chromatograms of research samples of eptifibatide manufactured by a new process and formulated into drug product. The identification of the unknown impurity was required in order to understand the mechanism of its formation. Th...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(03)00409-6
更新日期：2003-12-04 00:00:00
