Abstract：
:Hydrates are of great pharmaceutical relevance and even though they have been characterized thoroughly by various analytical techniques, there is barely literature available on molecular mobility of the hydrate water studied by NMR relaxation in the time domain. The aim of this work was to examine the possibility of differentiating hydration states of drugs by 1H time domain NMR (TD-NMR) regarding spin-spin and spin-lattice relaxation times (T2 and T1) using benchtop equipment. Caffeine and theophylline were selected as model compounds and binary mixtures of hydrate to anhydrate were analyzed for each drug using a spin echo and inversion recovery pulse sequence. It was possible to extract a signal that was specific for the water in the hydrates so that differentiation from anhydrous solid forms was enabled. Excellent calibrations were obtained for quantitative analysis of hydrate/anhydrate mixtures and predicted water contents were in good agreement with water amounts determined in desiccator sorption experiments. TD-NMR was therefore found to be a suitable new technique to characterize pharmaceutical hydrates in a non-invasive and hence sample-sparing manner. Quantification of the hydrate content in pharmaceutical mixtures appears highly attractive for product development and process monitoring. TD-NMR provides here a valuable and complementary technique to established process analytics, such as for example Raman spectroscopy.
journal_name
J Pharm Biomed Analjournal_title
Journal of pharmaceutical and biomedical analysisauthors
Schumacher SU,Rothenhäusler B,Willmann A,Thun J,Moog R,Kuentz Mdoi
10.1016/j.jpba.2017.01.017subject
Has Abstractpub_date
2017-04-15 00:00:00pages
96-103eissn
0731-7085issn
1873-264Xpii
S0731-7085(16)30613-6journal_volume
137pub_type
杂志文章abstract：:The controlled adsorptive accumulation of Zn(II)-terfenadine complex (1:1) onto a hanging mercury drop electrode (HMDE) provides the basis for determination of the antihistamine drug terfenadine by differential pulse cathodic adsorptive stripping voltammetry. The adsorbed Zn(II)-terfenadine complex (1:1) at the HMDE d...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(01)00491-5
更新日期：2001-11-01 00:00:00
abstract：:The electroreduction of ethinylestradiol at the hanging mercury drop electrode in the Britton-Robinson universal buffer of pH 2-11 was studied and its interfacial adsorptive character onto the mercury electrode surface was identified. A validated simple, rapid, sensitive, specific, precise and inexpensive square-wave ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2005.07.024
更新日期：2006-02-13 00:00:00
abstract：:Fentanyl, a potent analgesic drug, has traditionally been used intravenously in surgical or diagnostic operations. Formulations with fentanyl in oral transmucosal delivery system and in transdermal depot-patch have also been developed against breakthrough pain in cancer patients. In this report, LC-MS/MS methods to de...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2004.09.024
更新日期：2005-04-29 00:00:00
abstract：:A previously established method for the analysis of chlortetracycline by liquid chromatography using polystyrene-divinylbenzene stationary phases was examined in a multicentre study involving four laboratories and a total of 12 columns. Three chlortetracycline hydrochloride samples were analysed. The main component an...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(92)80029-m
更新日期：1992-02-01 00:00:00
abstract：:A novel drug-delivery system was developed by loading the anticancer drug, mitomycin C (MC) into an oil/water system with the aim of investigation by electrochemical sensing the interaction between the drug and DNA in microemulsion phase. The physical and physicochemical properties (droplet size, pH, viscosity, conduc...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2007.05.005
更新日期：2007-10-18 00:00:00
abstract：:An analytical methodology for the simultaneous determination of seven pharmaceuticals and two metabolites belonging to the non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics therapeutic groups was developed based on off-line solid-phase extraction and ultra-high performance liquid chromatography coupled to ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2014.06.017
更新日期：2015-03-15 00:00:00
abstract：:A simple reversed-phase high-performance liquid chromatography method was developed for the determination of s-carboxymethyl-l-cysteine in syrup preparations. The experiments were performed without specific sample pre-treatment. The LC conditions used were acetonitrile-10 mM sodium dihydrogenphosphate buffer, pH 2.0 (...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(00)00479-9
更新日期：2001-04-01 00:00:00
abstract：:The response of tumours to adriamycin, and the cardiotoxicity of the drug, may be related to its pharmacokinetics and plasma levels. Rapid and sensitive methods of adriamycin determination in plasma and urine samples are thus needed. A comparative study shows that high-performance liquid chromatography with fluorimetr...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(83)80042-9
更新日期：1983-01-01 00:00:00
abstract：:A direct and sensitive liquid chromatographic method for the determination of propofol in 50 microliters of plasma is described. The separation of the drug and internal standard (methyldopa) was achieved using a 4 microns particle size C1R cartridge (10 cm x 8 mm i.d.) in conjunction with a radial compression system a...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(96)01818-3
更新日期：1996-10-01 00:00:00
abstract：:In order to develop a radiopharmaceutical for hepatobiliary scintigraphy with better hepatobiliary properties new ligand for complexation of 99mTc, 4-iodo-2,6-dimethylphenylcarbamoylmethyl iminodiacetic acid (METHYLIODIDA), was synthesized. Acid-base equilibria of METHYLIODIDA were studied potentiometrically, because ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2004.03.009
更新日期：2004-09-03 00:00:00
abstract：:Enantiomers of clenbuterol were directly separated by a new high performance chromatographic method on Chirex 3005 column. Several parameters such as mobile phase composition, column temperature and flow rate were studied. Baseline enantioseparation was achieved, using the optimized mobile phase of n-hexane-1,2-dichol...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(02)00671-4
更新日期：2003-02-26 00:00:00
abstract：:Trans-3,5,4'-trihydroxystilbene (trans-resveratrol, RES) exhibits very low bioavailability due to extensive conjugative metabolism. Whether RES metabolites exhibit pharmacologic activity is of great interest. The present study aimed at synthesis of monoconjugates of RES - the 3- and 4' monosulfates (R3S and R4'S), and...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2011.12.006
更新日期：2012-04-07 00:00:00
abstract：:Mepitiostane (2α,3α-epithio-17β-(1-methoxycyclopentyloxy)-5α-androstane), which is a prodrug of epitiostanol (2α,3α-epitio-5α-androstane-17β-ol), is an epitiosteroid having anti-estrogenic and weak androgenic anabolic activities. The World Anti-Doping Agency prohibits the misuse of mepitiostane by athletes. Detection ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2015.07.016
更新日期：2015-11-10 00:00:00
abstract：:The simultaneous interaction of 15 steroidal drugs with tau-cyclodextrin (tauCD) and hydroxypropyl-beta-CD (HPbetaCD) was determined by charge transfer chromatography and the relative strength of interaction was calculated for each drug-tauCD-HPbetaCD ternary complex. The mixture of CDs interacted with each steroidal ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(99)00234-4
更新日期：2000-02-01 00:00:00
abstract：:A simple and rapid capillary electrophoresis method with UV detection was developed and validated for the determination of rufloxacin hydrochloride in coated tablets. An experimental design strategy (Doehlert design and desirability function) allowed the analytical parameters to be simultaneously optimized in order to...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(02)00054-7
更新日期：2002-06-15 00:00:00
abstract：:Capillary isotachophoresis (ITP) with conductimetric detection has been used for separating and determining bopindolol (I) in commercial mass-produced pharmaceutical preparations. The optimised operational electrolyte system consisted of 5 mM potassium picolinate and 5 mM picolinic acid (leading electrolyte, LE; pH 5....
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(01)00671-9
更新日期：2002-05-15 00:00:00
abstract：:A reversed-phase high-performance liquid chromatography (HPLC) method with dual optical rotation/UV absorbance detection has been developed for the determination of enantiomeric purity of ephedrine hydrochloride and pseudoephedrine hydrochloride using an achiral column. The method gave a correlation coefficient of 0.9...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(90)80050-y
更新日期：1990-01-01 00:00:00
abstract：:A novel strategy for predicting bioactive components in traditional Chinese medicines (TCM) using live cell extraction and high performance liquid chromatography-diode array detection-mass spectrometry (HPLC-DAD-MS) analysis was proposed. The hypothesis is that when cells are incubated together with the extract of TCM...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2006.01.014
更新日期：2006-05-03 00:00:00
abstract：:A method using reverse phase liquid chromatography-tandem mass spectrometry and cassette administration was developed for in vivo brain and plasma exposure profiling to assist early CNS drug discovery programs. Three to four compounds were grouped in cassettes for dosing and analysis. Compounds in the cassettes were s...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/S0731-7085(03)00523-5
更新日期：2004-02-04 00:00:00
abstract：:A non-aqueous capillary electrophoresis method for the determination of oxytetracycline in an ointment have been validated. The oxytetracycline (OTC) is separated from related impurities and degradation products as metal chelates with magnesium ions. Thus, the method show high selectivity. The sample preparation is pe...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(96)01998-x
更新日期：1997-05-01 00:00:00
abstract：:A reversed-phase gradient elution system with methanol-triethylammonium phosphate buffer (83.3 mM, pH 6.0) as eluent on C(18)-bonded silica is described for the separation of 38 ribonucleotides, deoxynucleotides, cyclic nucleotides and deoxycyclic nucleotides in less than 33 min. The retention of the nucleotides can b...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(86)80046-2
更新日期：1986-01-01 00:00:00
abstract：:Chlorogenic acids and derivatives like phenolic acids are potentially bioactive phenolics, which are commonly found in many foods. Once absorbed, chlorogenic and phenolic acids are highly metabolized by the intestine and the liver, producing glucuronidated and/or sulphated compounds. These metabolites were analyzed in...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2013.10.009
更新日期：2014-01-01 00:00:00
abstract：:After assay validation in an originating laboratory, an analytical method needs to be transferred to one or several production laboratories, because measured outcomes among the laboratories must agree. To state agreement, the locations (e.g. means) must be equivalent and the production laboratory must be non-inferior ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2012.10.032
更新日期：2013-02-23 00:00:00
abstract：:Platycladi Cacumen (PC) is a traditional Chinese medicine used for the treatment of hemorrhages, cough, asthma and hair loss. To get a better understanding of the chemical constituents in PC, ultra-high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectro...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2018.03.005
更新日期：2018-05-30 00:00:00
abstract：:A fast static headspace gas chromatography (HS-GC) method was developed to separate all residual solvents present in commercial active pharmaceutical ingredient (API) batches of permethrin. A total of six residual solvents namely 2-methylpentane, 3-methylpentane, methylcyclopentane, n-hexane, cyclohexane and toluene w...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2016.06.020
更新日期：2016-09-05 00:00:00
abstract：:Di(2-ethylhexyl)phthalate (DEHP), a plasticiser present in infusion equipment, is known to be harmful to human health. Various studies have shown that DEHP is released into drug solutions from polyvinyl chloride (PVC) infusion lines. New multi-layer tubing has therefore been marketed to overcome this problem. We asses...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2003.12.018
更新日期：2004-04-01 00:00:00
abstract：:This work describes the construction and evaluation of lactate sol-gel biosensors to accomplish the determination of lactate in pharmaceutical products. Lactate oxidase was incorporated in a porous sol-gel film placed onto a platinum-based electrode. Acid and basic catalysis were assessed. When coupled to a sequential...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2006.11.027
更新日期：2007-03-12 00:00:00
abstract：:A comprehensive study of fragmentation pathways of 15-membered azalide macrocycles using electrospray ionisation with multistage mass spectrometry (ESI-MS(n)) is presented in this work. Hydrogen/deuterium (H/D) exchange experiments and high-resolution mass spectrometry were used to investigate the proposed fragmentati...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2013.07.011
更新日期：2013-12-01 00:00:00
abstract：:A simple high-performance liquid chromatographic assay with using UV detection (266 nm) was developed to determine a novel gastroprokinetic agent, Z-338 in dog plasma. The extraction procedure using solid-phase extraction with a Isolute SCX column produces extremely clean eluates and a high recovery. Intra- and inter-...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(00)00593-8
更新日期：2001-06-01 00:00:00
abstract：:The use of multivariate spectrophotometric calibration is reported for the analysis of two decongestant tablets, where paracetamol is the principal component and diphenhydramine or phenylpropanolamine are the minor components. The resolution of these mixtures has been accomplished without prior separation or derivatis...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(99)00029-1
更新日期：1999-06-01 00:00:00
