Abstract：
:The stability of a series of fluorescent isoindoles formed under analytical conditions following the reaction of o-phthalaldehyde (OPA) and ethanethiol (ET) with a series of primary amines is reported. Increasing the bulk and degree of substitution of the isoindole N-substituent resulted in substantial increases in isoindole stability. The effects of excess reagents on isoindole stability is examined and OPA is observed to accelerate isoindole degradation whilst ET provides a stabilizing effect. Comparison with previously reported data involving the use of 2-mercaptoethanol revealed that ET clearly forms the more stable isoindole derivatives, i.e. a minimum of five-fold improved stability based on the time for 10% degradation to occur. Identification of the major degradation product together with kinetic data suggests that degradation proceeds via autoxidation.
journal_name
J Pharm Biomed Analjournal_title
Journal of pharmaceutical and biomedical analysisauthors
Stobaugh JF,Repta AJ,Sternson LAdoi
10.1016/0731-7085(86)80056-5subject
Has Abstractpub_date
1986-01-01 00:00:00pages
341-51issue
3eissn
0731-7085issn
1873-264Xpii
0731-7085(86)80056-5journal_volume
4pub_type
杂志文章abstract：:An automated solid-phase extraction workstation was used to develop, characterize and validate two separate HPLC methods for quantifying drugs in plasma. Method development was facilitated by workstation functions which allowed wash solvents of varying organic composition to be mixed and tested automatically. The prec...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(97)00278-1
更新日期：1998-08-01 00:00:00
abstract：:The health benefits of almonds along with their ability to prevent atheroschlerosis as well as cardiovascular and diabetes risks are well known. Previous works were focused mainly on the lipid fraction, thus a lack of information about the polar constituents still persists. In order to provide deeper insight into the ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2020.113518
更新日期：2020-10-25 00:00:00
abstract：:Cyclodextrins are cyclic oligosaccharides able to form inclusion complexes with a variety of hydrophobic guest molecules, positively modifying their physicochemical properties. A thorough analytical characterization of cyclodextrin complexes is of fundamental importance to provide an adequate support in selection of t...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章,评审
doi：10.1016/j.jpba.2015.01.058
更新日期：2015-09-10 00:00:00
abstract：:An electrochemical method for quantifying beta-lactam antibiotics (cephalexin and ampicillin) and their hydrolysis products is described. Cyclic voltammetry at the water/nitrobenzene interface in a four-electrode system was used. The zwitterionic compounds were ionized to the necessary electrochemical form by pH adjus...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(98)00147-2
更新日期：1999-02-01 00:00:00
abstract：:The hydroxide-catalyzed non-enzymatic hydrolysis of cocaine is quantified in terms of ten site- and species-specific rate constants in connection with also ten site- and species-specific acid-base equilibrium constants, comprising all the twelve coexisting species in solution. This characterization involves the major ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2017.07.005
更新日期：2017-10-25 00:00:00
abstract：:Protein modification generally occurs by addition to the amino acid side-chains of protein at the post-translational stage, for example, by enzymatic or chemical reactions after polypeptide synthesis. Recently, the recombinant hirudin analog CX-397, a potent thrombin inhibitor, was found to contain methylated Ile resi...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章,评审
doi：10.1016/s0731-7085(02)00703-3
更新日期：2003-04-01 00:00:00
abstract：:A stability study for amodiaquine (AQ) and desethylamodiaquine (AQm) in whole blood and plasma is reported. AQ, AQm and chloroquine (CQ) were simultaneously analysed and the ratios AQ/CQ and AQm/CQ were used to ensure correct interpretation of the stability results. CQ was stable in whole blood and plasma at all teste...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2005.10.018
更新日期：2006-04-11 00:00:00
abstract：:The Mahuang-Xingren herb-pair (MX), the combination of Herba Ephedrae (Mahuang in Chinese) and Semen Armeniacae Amarum (Xingren in Chinese), is a classical combination used in traditional Chinese Medicine to treat asthma and bronchitis. A simple and reliable ultra-performance liquid chromatography-tandem mass spectrom...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2015.02.004
更新日期：2015-05-10 00:00:00
abstract：:Recently it was found that normal adults excrete pipecolic acid primarily as the D-enantiomer even though it is present in the blood stream mainly as the L-enantiomer (i.e. > 98% L). This study of pipecolic acid stereochemistry was extended to subjects with peroxisomal deficiencies since they are known to have high le...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(93)80044-2
更新日期：1993-10-01 00:00:00
abstract：:This paper describes a new liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the analysis of three stanozolol metabolites (16β-hydroxystanozolol, 3'-hydroxystanozolol, and 4β-hydroxystanozolol) in urines of animal origins. The solid-phase extraction (SPE) clean-up procedure was optimized to reduce ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2013.08.019
更新日期：2014-01-01 00:00:00
abstract：:Quantitative whole-body autoradiography (QWBA) and liquid scintillation counting (LSC) have been conducted to determine the metabolic profiles and tissue distribution of [(14)C] labeled artesunate (AS) injection in rats. The QWBA technique showed more accurate results in the quantification of radioactivity in 40 organ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2008.07.015
更新日期：2008-11-04 00:00:00
abstract：:In this study, the development and validation of a high-performance liquid chromatography (HPLC) assay for determination of repaglinide concentration in human plasma for pharmacokinetic studies is described. Plasma samples containing repaglinide and an internal standard, indomethacin were extracted with ethylacetate a...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2006.12.010
更新日期：2007-04-11 00:00:00
abstract：:Several methods are reported for the simultaneous determination of diazepam and pyridoxine: two graphical methods (zero-crossing and derivative quotient spectra); and two numerical methods (multiple linear regression and partial least-squares regression). The methods have been applied in the concentration ranges 1.4-4...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(96)01844-4
更新日期：1996-11-01 00:00:00
abstract：:A dedicated proteomic approach based on nano-Liquid Chromatography coupled with tandem mass spectrometry in ion trap is proposed for the analysis of proteins trapped in sorbent resin cartridges used to remove inflammatory mediators from blood by coupled plasma filtration adsorption (CPFA). The final purpose of the pro...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2016.10.009
更新日期：2017-01-05 00:00:00
abstract：:Three methods are described for the simultaneous determination of mebeverine hydrochloride (MB) and sulpiride (SU) in combined pharmaceutical tablets. The first method depends on first-derivative ultraviolet spectrophotometry, with zero-crossing measurement method. The first derivative amplitudes at 214.2 and 221.6 nm...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(99)00176-4
更新日期：1999-11-01 00:00:00
abstract：:A rapid, specific and very sensitive liquid chromatographic assay using standard ultraviolet detection has been developed to measure cefazolin (CFZ) or ceftriaxone (CFX) in small samples (200 microl) of plasma using either drug as the internal standard for measurement of the other. A rapid extraction was performed usi...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(99)00273-3
更新日期：2000-03-01 00:00:00
abstract：:The coupling of sequential injection analysis (SIA) and fluorimetric solid phase transduction is here applied to the determination of paracetamol in pharmaceuticals. The reaction product between the analyte and sodium nitrite in acidic medium is inserted, after alkalinization, in the system. This product is transitori...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2007.05.004
更新日期：2007-10-18 00:00:00
abstract：:Ultra-violet (UV) spectrophotometric and high performance liquid chromatographic methods for quantitative determination of ellagic acid (EA), an antioxidant were developed. The analytical methods were validated for linearity, accuracy, intra- and inter-day variability, and precision. EA was eluted using a polyethylene...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2005.07.006
更新日期：2006-01-23 00:00:00
abstract：:DuP 747, a selective kappa agonist analgesic, was found to have at least two polymorphic forms, and this was confirmed by X-ray powder diffraction. DSC and thermomicroscopic studies indicated the polymorphic pair to be monotropic. Solubility studies suggested the relative stability of the two forms to be similar. The ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(94)e0002-i
更新日期：1994-06-01 00:00:00
abstract：:Strategies for the use of 1H and 19F nuclear magnetic resonance (NMR) spectroscopy as an aid to the study of the metabolic fate of fluorinated drugs are discussed with reference to the application of these methods to flurbiprofen metabolism in man. 1H and 19F NMR analysis of untreated urine enabled the detection of tw...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(90)80067-y
更新日期：1990-01-01 00:00:00
abstract：:Regulations alarmed the control of genotoxic impurities in drug substances at lower level based on the threshold of toxicological concern and daily dose. This review explores the details of various regulations and guidances, toxicology assessment, identification of structural alerts, synthetic origins, different synth...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章,评审
doi：10.1016/j.jpba.2010.11.039
更新日期：2011-06-25 00:00:00
abstract：:There is increasing evidence that amino acids and related compounds are among the most important metabolites for living systems and their quantitative analysis is a continuous challenge for clinical and biochemical laboratories. The lack of chromophore group and their high polarity make the analytical process more dif...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2012.03.017
更新日期：2013-01-25 00:00:00
abstract：:Furazadrol ([1',2']isoxazolo[4',5':2,3]-5α-androstan-17β-ol) is a designer anabolic androgenic steroid that is readily available via the internet. It contains an isoxazole fused to the steroid A-ring which offers metabolic stability and noteworthy anabolic activity raising concerns over the potential for abuse of this...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2016.02.031
更新日期：2016-05-30 00:00:00
abstract：:A new sildenafil analog has been identified in the softgel shell of a dietary supplement. The compound was investigated by UV spectroscopy and high-resolution MS analysis, leading to the proposed structure 1-methyl-5-{5-[2-(4-methylpiperazin-1-yl)acetyl]-2-propoxyphenyl}-3-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidi...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2018.08.031
更新日期：2018-11-30 00:00:00
abstract：:A thermospray liquid chromatography/mass spectrometry (TSP-LC/MS) method is described for determination of the enantiomeric excess of alpha-amino acids and alpha-amino acid amides as their o-phthalaldehyde/N-acetyl-L-cysteine (OPA/NAC) derivatives. The source temperature is an important factor in optimizing the sensit...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(95)01580-9
更新日期：1995-11-01 00:00:00
abstract：:A method for the analysis of aqueous samples of isosorbide-5-mononitrate (5-ISMN) is presented. It is based on packed column supercritical fluid chromatography (SFC) using 20% of 2-propanol in carbon dioxide as the mobile phase and a diol silica column as the stationary phase. Using the described conditions it is poss...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(02)00072-9
更新日期：2002-06-20 00:00:00
abstract：:We describe here the development of a new, non-isotopic immunological assay termed CMIA (carbonyl metallo immunoassay) that uses metal carbonyl complexes as tracers and Fourier transform infrared spectroscopy (FT-IR) as the detection method. This assay is based on the particular spectral features of these complexes, w...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(99)00169-7
更新日期：1999-11-01 00:00:00
abstract：:750 MHz 1H NMR spectroscopy has been used to characterise in detail the abnormal low molecular weight metabolites of urine from two patients with inborn errors of metabolism. One case of the rare condition 2-hydroxyglutaric aciduria has been examined. There is at present no rapid routine method to detect this genetic ...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/s0731-7085(97)00066-6
更新日期：1997-07-01 00:00:00
abstract：:An analytical method for nipecotic acid quantification in rat blood was developed utilizing a stable isotope internal standard and capillary gas chromatography-mass spectroscopy. The method involves a solid phase extraction step followed by a two-step derivatization. The analytes are separated by capillary gas chromat...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/j.jpba.2003.11.019
更新日期：2004-03-10 00:00:00
abstract：:The photochemistry of 4-aminobenzoic acid has been investigated using two validated reversed-phase HPLC methods. Up to nine photoproducts have been detected, with chromatographic evidence for the formation of 4,4'-azobenzenedicarboxylic acid and 4,4'-hydrazobenzenedicarboxylic acid. The synthesis and analytical charac...
journal_title：Journal of pharmaceutical and biomedical analysis
pub_type： 杂志文章
doi：10.1016/0731-7085(96)01808-0
更新日期：1996-08-01 00:00:00
