Simultaneous determination of theophylline and dyphylline by micellar electrokinetic chromatography and application in drug formulations

Huang, Wei-Shan; Lin, Shuo; Wu, Hsin Lung; Chen, Su‐Hwei

doi:10.1016/s1570-0232(03)00601-9

Cited by 14 publications

(5 citation statements)

References 22 publications

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“…Drug determinations have been accomplished in plasma [117,138,141,142], urine [60,68,81], serum [79,117,[143][144][145], cerebral spinal fluid [141], and cell lines [125]. Impurity (and purity) analysis of drugs [18,59], preparations [146], and tablets [102,[147][148][149] have also been demonstrated with MEKC. Other reports have demonstrated means of determining metabolites [60,68,81,117,125], degradation products [92] and constituent analysis [65,94,150,151].…”

Section: Pharmaceuticalsmentioning

confidence: 99%

Recent advances in micellar electrokinetic chromatography

2005

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This review contains nearly 200 reference citations, and covers advances in electrokinetic capillary chromatography based on micelles, including stabilized micelle complexes, polymeric and mixed micelles from 2003-2004. Detection strategies, analyte determinations, and applications in micellar electrokinetic capillary chromatography (MEKC) are discussed. Information regarding methods of analyte concentration, analyte specific analyses, and nonstandard micelles has been summarized in tabular form to provide a means of rapid access to information pertinent to the reader.

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Section: Pharmaceuticalsmentioning

confidence: 99%

Recent advances in micellar electrokinetic chromatography

2005

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“…Diprophylline is the N 7 -substituted derivative of theophylline naturally found in tea and cocoa beans [ 1 , 2 ]. Diprophylline and theophylline are both methylxanthines usually employed for symptomatic relief or prevention of bronchi asthma and chronic obstructive pulmonary disease clinically [ 3 ]. Compared with theophylline, diprophylline causes fewer adverse drug reactions [ 4 ] and has a wider therapeutic window and a more effective relaxant effect [ 5 , 6 ].…”

Section: Introductionmentioning

confidence: 99%

Characteristics of Diprophylline-Induced Bidirectional Modulation on Rat Jejunal Contractility

Liu

Chen

Xiong

et al. 2014

Korean J Physiol Pharmacol

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In this study, we propose that diprophylline exerts bidirectional modulation (BM) on the isolated rat jejunal segment depending on its contractile state. The results supported the hypothesis. Diprophylline (20 µM) exerted stimulatory effects on the contractility of jejunal segment in six low contractile states while inhibitory effects in six high contractile states, showing the characteristics of BM. Diprophylline-induced stimulatory effect was significantly blocked by atropine, indicating the correlation with cholinergic activation. Diprophylline-induced inhibitory effect was partially blocked by phentolamine, propranolol, and L-N-Nitro-Arginine respectively, indicating their correlation with sympathetic activation and nitric oxide-mediated relaxing mechanisms. Diprophylline-induced BM was abolished by tetrodotoxin or in a Ca2+ free condition or pretreated with tyrosine kinase inhibitor imatinib, suggesting that diprophylline-induced BM is Ca2+ dependent, and that it requires the presence of enteric nervous system as well as pacemaker activity of interstitial cells of Cajal. Diprophylline significantly increased the reduced MLCK expression and myosin extent in constipation-prominent rats and significantly decreased the increased MLCK expression and myosin extent in diarrhea-prominent rats, suggesting that the change of MLCK expression may also be involved in diprophylline-induced BM on rat jejunal contractility. In summary, diprophylline-exerted BM depends on the contractile states of the jejunal segments, requires the presence of Ca2+, enteric nervous system, pacemaker activity of interstitial cells of Cajal, and MLCK-correlated myosin phosphorylation. The results suggest the potential implication of diprophylline in relieving alternative hypo/hyper intestinal motility.

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“…A number of studies have been published during the past 15 years, which have been directed toward the characterization of the cytochrome p 450 (cyp) isoforms involved in the different pathways. Reported analytical procedures for theophylline metabolites in body fluids have been based on the methods of liquid chromatography with ultraviolet, [1][2][3][4][5][6][7][8][9] electrochemical, [10][11][12] immunoassay [13][14] and capillary electrophoresis detection. [15][16] In a previous investigation the advantage of using a solvent program 1,2,6,8 and ternary solvent 4,5,7,9 for LC-UV determination of theophylline and its metabolites in serum and urine samples was established.…”

Section: Introductionmentioning

confidence: 99%

Use of a Disposable Modified Carbon Paste Electrode for Liquid Chromatography‐amperometric Detection of Theophylline and Three Metabolites in Human Serum

Wang¹,

Tien²,

Tai³

2006

J Chinese Chemical Soc

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Chemically modified electrodes, constructed by incorporating potassium hexachloroplatinate K 2 PtCl 6 into the graphite power/paraffin oil matrix used to fabricate conventional carbon paste electrodes, were shown to catalyze the electrooxidation of purine compounds including theophylline, 3-methylxanthine, 1,3-dimethyluric acid and 1-methyluric acid; the modifier electrodes display electrocatalytic activity for the oxidation of purines at 170 mV (vs Ag/AgCl) when used as sensing electrodes in amperometric detection following liquid chromatography. The K 2 PtCl 6 electrodes permitted detection of the purines at similar values of applied potential. The limit of detection (LOD) of theophylline, 1-MUA, 3-MXT and 1,3-DMUA were 1.1 ng mL -1 , 3.2 ng mL -1 , 1.0 ng mL -1 and 11 ng mL -1 , respectively. The calibration graphs were linear for theophylline and metabolites over the range of concentration used (50-3200 ng mL -1 ). Theophylline and its metabolites can easily be separated and analyzed in one run using electrochemical sensor chromatography with a methanol -phosphate buffer containing 20 mM di-potassium hydrogen phosphate (pH 5.50). Serum samples were collected after the oral administration of black tea from human volunteers. Quantitative data for the determination of a micromolar amount of theophylline and its metabolites in serum samples are in agreement with data obtained by HPLC-UV.

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Simultaneous determination of theophylline and dyphylline by micellar electrokinetic chromatography and application in drug formulations

Cited by 14 publications

References 22 publications

Recent advances in micellar electrokinetic chromatography

Recent advances in micellar electrokinetic chromatography

Characteristics of Diprophylline-Induced Bidirectional Modulation on Rat Jejunal Contractility

Use of a Disposable Modified Carbon Paste Electrode for Liquid Chromatography‐amperometric Detection of Theophylline and Three Metabolites in Human Serum

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