Benzodiazepines, determination

The influence of lipid phase (gel or liquid crystalline), cholesterol content, lipid composition (egg phosphatidylcholine or DPPC), and structure of benzodiazepines determine their localization in the membrane. The strength of benzodiazepine-membrane interaction increases with a decrease in molecular order, molecular packing, and hydration,. The authors point to the pharmacological relevance of theses results because the extent of partitioning of these drags into biomembranes would be coupled to local oscillation of membrane dynamics which may be induced by physiological events. ... 

C,M,nalo,Meth Par,benzodiazepines Determination M in serum, electrochemical detection Lichrosorb RP18 300x4 MeOH-O.OlM KH2P04(85 15) 69... 

DETERMINATION OF 1-OCTANOL - WATER AND MICELLAR PSEUDOPHASE - WATER PARTITION COEFFICIENTS OF BENZODIAZEPINES... 

The comparison of predicting capabilities of two kinds of hydrophobicity evaluations is of interest. For these purpose partition coefficients P and P for a number of benzodiazepines gidazepam (I), medazepam (II), nitrazepam (III), oxazepam (IV), lorazepam (V) and diazepam (VI) were determined. 

Distribution of benzodiazepines in system micellar pseudophase - water was investigated in micellar solutions of sodium dodecylsulfate. The protonization constants of benzodiazepines were determined by the UV-spectophotometry. Values of protonization constants increase with increasing of sodium dodecylsulfate concentration. The binding constants of two protolytic forms of benzodiazepines with a micellar pseudo-phase and P, values were evaluated from obtained dependence. 

R. Herraez-Heruandez, A. J. H. Eouter, N. C. van de Merbel and U. A. Th Brinkman, Automated on-line dialysis for sample preparation for gas cliromatogruphy determination of benzodiazepines in human plasma , 7. Pharm. Biomed. Anal. 14 1077-1087 (1996). 

Benzodiazepine enantiomers have also been resolved on the Chiralcel OD CSP. Wang et al. utilized this CSP to determine the enantiomeric composition of camazepam and its metabolites [59]. SFC provided improved resolution of the compounds of interest in a shorter period of time than LC. Phinney et al. demonstrated the separation of a series of achiral and chiral benzodiazepines. An amino column was coupled in series with the Chiralcel OD CSP to achieve the desired separation [41]. 

Benzodiazepines. Figure 3 Dissection of benzodiazepine pharmacology. The functional roles of GABAa receptor subtypes, mediating particular actions of diazepam, are indicated. A sign indicates that the respective response is mediated by the respective receptor subtype, a sign indicates that the respective response is apparently not mediated by the respective receptor subtype. ND = not determined. 

Ciraulo DA, Jaffe JH Tricyclic antidepressants in the treatment of depression associated with alcoholism. Clin Psychopharmacol 1 146—150, 1981 Ciraulo DA, Nace E Benzodiazepine treatment of anxiety or insomnia in substance abuse patients. Am J Addict 9 276—284, 2000 Ciraulo DA, Barnhill JG, Jaffe JH, et al Intravenous pharmacokinetics of 2-hydroxy-imipramine in alcoholics and normal controls. J StudAlcohol 51 366-372, 1990 Ciraulo DA, Knapp CM, LoCastro J, et al A benzodiazepine mood effect scale reliability and validity determined for alcohol-dependent subjects and adults with a parental history of alcoholism. Am J Drug Alcohol Abuse 27 339—347, 2001 Collins MA Tetrahydropapaveroline in Parkinson s disease and alcoholism a look back in honor of Merton Sandler. Neurotoxicology 25 117-120, 2004 COMBINE Study Research Group Testing combined pharmacotherapies and behavioral interventions in alcohol dependence rationale and methods. Alcohol Clin Exp Res 27 1107-1122, 2003a... 

Farde L, Pauli S, Litton JE, et al PET-determination of benzodiazepine receptor binding in studies on alcoholism. EXS 71 143—153, 1994... 

Bleich A, Gelkopf M, Weizman T, et al Benzodiazepine abuse in a methadone maintenance treatment clinic in Israel characteristics and a pharmacotherapeutic approach. Isr J Psychiatry Relat Sci 39 104-112, 2002 Bohn LM, Gainetdinov RR, Lin FT, et al Mu-opioid receptor desensitization by beta-arrestin-2 determines morphine tolerance but not dependence. Nature 408 720— 723, 2000... 

Busto U, Simpkins], Sellers EM, et al Objective determination of benzodiazepine use and abuse in alcoholics. Br J Addict 78 429 35, 1983... 

Ciraulo DA, Knapp CM, LoCastro JS, et al A benzodiazepine mood effect scale reliability and validity determined for alcohol-dependent subjects and adults with a parental history of alcoholism. Am J Drug Alcohol Abuse 27 339—347, 2001... 

If withdrawal is from alcohol, administer the CIWA-Ar to determine withdrawal severity. A score of 8 to 10 denotes relatively mild withdrawal, and the patient can be treated as an outpatient with supportive care only. A score from 11 to 14 can be treated on either an outpatient or inpatient basis, with either supportive care or with benzodiazepines, depending on the presence of underlying medical problems and the prior history of... 

Further, the removal of benzodiazepine sensitivity in a selective a subunit in a mouse using the gene knockin technique has established that the al subunit plays a major role in the sedative and amnesiac effects of benzodiazepines, part of the anticonvulsant effect and little of the anxiolytic effect the latter effects are more importantly mediated by the a2 subunit [5, 6], The 0 subunit selectivity for the drugs loreclezole (an anxiolytic) and etomidate (an anesthetic) allowed determination that a single residue in the M2 domain could account for this selectivity (02 = 03 >01). When a mouse knockin selectively removed the etomidate sensitivity of the 02 subunit, the animals showed reduced sensitivity to sedative effects of etomidate but no reduction of the true anesthetic effects. In contrast, mutation of the 03 subunit to negate etomidate sensitivity of that subunit alone resulted in a mouse with no sensitivity to the anesthesia produced by etomidate. This proved that the GABA receptor is the target of at least this one anesthetic (etomidate) and, furthermore, that the specific locations in the brain of 03 subunits are important for anesthetic action, while the... 

Zweigenbaum J. Heinig K. Steinbomer S. Wachs T. Henion J. High Throughput LC/MS/MS Determination of Benzodiazepines in Human Urine-1000 sample per 12 Hours. Analytical Chemistry, 1999, 71, 2294-2300. 

Medina JH, Viola H, Wolfman C, Marder M, Wasowski C, Calvo D, Paladini AC. (1997). Overview— flavonoids a new family of benzodiazepine receptor ligands. Neurochem Res. 22(4) 419-25. Menghini A, Mancini LA. (1988). TLC determination of flavonoid accumulation in clonal populations of Passiflora incarnata L. Pharmacol Res Commun. 20(suppl 5) 113-16. 

Inoue H, Maeno Y, Iwasa M, Matoba, R, Nagas M. 2000. Screening and determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatogra-phy/mass spectrometry. Forensic Sci Int 113 367. 

Tanaka E, Terada M, Misawa S, Wakasugi C. 1998. Erratum to Simultaneous determination of twelve benzodiazepines in human serum using a new reversed-phase chromatographic column on a 2um porous microspherical silica gel. J Chromatogr B Biomed Appl 709(2) 324. [J Chromatogr B 682 (1996) 173]. 

Wilhelm M, Battista HJ, Obendorf D. 2001. HPLC with simultaneous UV and reductive electrochemical detection at the hanging mercury drop electrode a highly sensitive and selective tool for the determination of benzodiazepines in forensic samples. J Anal Toxicol 25(4) 250-257. 

Miki A, Tatsuno M, Katagi M, Nishikawa M, Tsuchihashi H. 2002. Simultaneous determination of eleven benzodiazepine hypnotics and eleven relevant metabolites in urine by column-switching liquid chromatography-mass spectrometry. J Anal Toxicol 26 87. 

Toyo oka T, Kumaki Y, Kanbori M, Kato M, Nakahara Y. 2003. Determination of hypnotic benzodiazepines (alprazolam, estrazolam, and midazolam) and their metabolites in rat hair and plasma by reversed-phase liquid-chromatography with electrospray ionization mass spectrometry. J Pharm Biomed Anal 30 1773. 

A series of tubes containing assay buffer (50 mM Tris/HCl, 150 mM KCl, pH 7.4), radioiabeiied benzodiazepine (typically 0-50 nM) and bovine brain membranes (final concentration 0.5 mg/ml or approximately 1 nM in benzodiazepine binding sites) is set up. Nonspecific binding is determined in the presence of an excess of unlabelled benzodiazepine. As some benzodiazepines are light sensitive, we usually use opaque amber tubes for these assays. 

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