Morphine determination

Determination of morphine using chronoamperometric transduction may serve as an example of the competitive procedure presented above [25], The linear dynamic concentration range was 0.1-10 pg mL 1 morphine. Codeine played the role of an electroinactive competitor. Microorganism contamination was removed from the MIP film prior to morphine determination using an autoclave. Performance of this chemosensor was much improved with respect to those of traditional biosensors in terms of stability under extremely harsh chemical conditions and elevated temperature. 

Jeger, A. N., Raas, R. E., Hamberg, C., Briellmann, T., Morphine Determination in Hrnnan Hair by Instrumental HPTLC, Comae Bibliogr. Serv., 68, 7,1992. 

AM Bermejo, et al. Morphine determination by gas chromatography mass spectroscopy in human vitreous humor and comparison with radioimmunoassay. J Anal Toxicol 16 372, 1992. 

C.F. McLean, L.E. Mather, J. Odontiadis and P.A. Sloan, Improved method for morphine determination in biological fluids and tissues rapid, sensitive and selective, J. Pharm. Pharmacol, 1990, 42, 669-671,... 

The ipecacuanha in this preparation does not interefere with the morphine determination "... 

Salem and Galan have developed a new method for determining the amount of morphine hydrochloride in tablets. Results, in milligrams, for several tablets containing different nominal dosages follow... 

Estimation of Morphine in Opium. The problem of determining with reasonable accuracy the percentage of morphine in opium is of importance for the standardisation of medicinal opium, as a means of fixing the price of crude opium, and of controlling factory operations in the extraction of... 

The first scheme for the separation of the six chief alkaloids of opium, VIZ., morphine, codeine, thebaine, papaverine, narcotine and narceine, is probably that of Plugge. Much later Kljatschkina investigated for each of these six bases the properties by means of which isolation and estimation could probably be effected and, on the basis of the results, devised a plan for such analyses. More recently Anneler has published a detailed account of a scheme with the same objective. l Attention had already been given to complex, systematic analyses of this kind, in connection with examination of the mixtures of opium alkaloids, which have long been in use in medicine in these at first only morphine and other alkaloids were determined, but in the more recent schemes provision is made for the estimation of each alkaloid. ... 

Figure 11.12 GC analysis of (a) urine sample spiked with opiates 3 p.g/ml) and (b) blank urine sample. Peak identification is as follows 1, dihydrocodeine 2, codeine 3, ethylmor-phine 4, moipliine 5, heroin. Reprinted from Journal of Chromatography, A 771, T. Hyotylainen et al., Determination of morphine and its analogues in urine by on-line coupled reversed-phase liquied cliromatography-gas clrromatography with on-line derivatization, pp. 360-365, copyright 1997, with permission from Elsevier Science.

This experiment33 illustrates how adjustment of pH may be used to control fluorescence and so make the determination more specific. The alkaloids codeine and morphine can be determined independently because whilst both fluoresce strongly at the same wavelength in dilute sulphuric acid solution, morphine gives a generally negligible fluorescence in dilute sodium hydroxide. The fluorescence intensities of the two compounds are assumed to be additive. 

Bohn LM, Gainetdinov RR, Lin FT et al (2000) p-Opioid receptor desensitization by (3-arrestin-2 determines morphine tolerance but not dependence. Nature 408 720-723... 

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... 

Note not all patients with mastocytosis have reactions provoked by all factors. For example, many patients with mastocytosis tolerate radiocontrast media, anesthesia, morphine, dextrometorphan, aspirin, and other analgesics. When in question, patients should undergo graded challenges to determine sensitivity. 

Colorimetric procedures used In steroid assays are often subject to drug Interference. In the determination of 17-Ketosterolds by the Zimmerman reaction, drugs with the 17-Keto basic structure such as ascorbic acid, morphine and reserplne will cause Increased values. In the determination of 17,21 -dlhydroxysterolds by the Porter-Sllber reaction the dlhydroxy-acetone chain Is the reactive unit. Drugs like meprobamate, chloral hydrate, chloropromazlne and potassium Iodide will Interfere with this reaction and cause elevated values. In the colorimetric determination of vanlllylmandellc acid (VMA) by a dlazo reaction, drugs like methocarbamol and methyl dopa cause... 

The relative extent of the unwanted effects caused by selective agonists at the different opioid receptors is of great importance in determining if non-mu opioids will have better spectra of actions as compared to morphine. However, there are good indications that the kappa and delta receptor agonists cause less respiratory depression than mu... 

Hyotylainen, T., Siren, H., and Riekkola, M.L., Determination of morphine analogues, caffeine and amphetamine in biological fluids by capillary electrophoresis with the marker technique, J, Chromatogr., 735,439,1996... 

Figure 5.7 shows lipophilicity profiles (log D vs. pH) for an acid (warfarin), a base (tetracaine), and an ampholyte (morphine). The dashed curves correspond to the values determined in octanol-water and the solid curves, to values in liposome-water. As is readily apparent, the major differences between octanol and liposomes... 

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