Paracetamol identification

The successful use of MEKC for the analysis of illicit heroin and cocaine was also reported by Staub and Plaut (1994), who used 50 mM SDS in phosphate-borate buffer (10 and 15 mM, respectively) containing 15% of acetonitrile (pH 7.8). In 25 minutes, these authors achieved separation and determination of paracetamol, caffeine, 6-monoacetylmorphine (6-MAM), acetylcodeine, procaine, papaverine, heroin, and noscapine, although with peaks sometimes skewed. On-line recorded UV spectra of the peaks helped the identification of the individual peaks. 

K. Pusecker, J. Schewitz, P. Gfrorer, L.-H.Tseng, K. Albert, E. Bayer, I. D. Wilson, N. J. Bailey, G. B. Scarfe, J. K. Nicholson, and L. C. Lindon, On-flow identification of metabolites of paracetamol from hnman urine nsing directly coupled CZE-NMR and CEC-NMR spectroscopy, A aZ. Commun. 35 (1998), 213-215. 

Shinde et al. 1138] developed a simple, rapid and reliable HPTLC method for simultaneous identification and quantification of paracetamol and diclofenac sodium in pharmaceutical preparations. They performed chromatography on silica 60 F154 plates, and used ketorolac tromethamine as internal standard. 

In Norway, Wieders Farmasoytiske A/S received approval for the use of NIR as an alternative method for identification, assay, and determination of moisture content of paracetamol (acetaminophen) tablets. The Norwegian Medicines Control Authority approved the method in December 1996. 

Given the role of NMR in dmg metabolism smdies, on-hne LC-NMR or LC-NMR-MS is highly attractive [51]. This is demonstrated in a number of applications, e.g., in identification of minary metabolites of acetaminophen [52], and paracetamol [53], and the novel non-nucleoside reverse transcriptase inhibitor GW 420867 [54]. Nowadays, this expensive technique is frequently applied. It is commercially available. 

Pusecker, K. Schewitz, J. Gfrorer, P. Tseng, L.-H. Albert, K. Bayer, E. Wilson, I.D. Bailey, N.J. Scarfe, G.B. Nicholson, J.K. Lindon, J.C. On-flow identification of metabolites of paracetamol from human urine using directly coupled CZE-NMR and CEC-NMR spectroscopy. Anal. Commun. 1998, 35, 213-215. 

Several studies have used NMR spectroscopy to determine the number and identity of drug metabolites in bile. These include the use of NMR spectroscopy to study doxifluridine catabolites in human bile, and C NMR spectroscopy of perfluorinated fatty acids in rat bile and NMR for monitoring the formation of formaldehyde from demethylation of antipyrine. NMR spectroscopy of rat bile has been used to monitor the excretion of paracetamol metabolites. A combination of H and H- - C 2D NMR methods has allowed identification of 4-cyano-A,N-dimethylaniline, cefoperazone and benzyl chloride in rat bile. ... 

Weis M, Kass GE, Orrenius S (1994) Further characterization of the events involved in mitochondrial Ca2+ release and pore formation by prooxidants. Biochem Pharmacol 47 2147—2156 Welch KD, Reilly TP, Bourdi M, Hays T, Pise-Masison CA, Radtmovich MF, Brady JN, Dix DJ, Pohl LR (2006) Genomic identification of potential risk factors during acetaminophen-induced liver disease in susceptible and resistant strains of mice. Chem Res Toxicol 19 223-233 Wendel A, Feuerstein S, Konz KH (1979) Acute paracetamol intoxication of starved mice leads to lipid peroxidation in vivo. Biochem Pharmacol 28 2051-2055 Yamada Y, Kirillova I, Peschon JJ, Fausto N (1997) Initiation of liver growth by tumor necrosis factor deficient liver regeneration in mice lacking type I tumor necrosis factor receptor. Proc Natl Acad Sci USA 94 1441-1446... 

Spraul M, Hofmann M, Lindon JC, Farrant RD, Seddon MJ, Nicholson JK, WUson ID. Evaluation of liquid-chromatography coupled with high-field H NMR spectroscopy for drug metabolite detection and characterization the identification of paracetamol metabolites in urine and bile. NMR Biomed 1994 7 295-303. 

Liquid chromatography (HPLC) (a) Analysis of suspected doping agents in race horses (b) Identification of paracetamol in blood. 

Estimation and Identification in Blood Plasma of Paracetamol (N-Acetyl-p-aminophenol) in the Presence of Barbiturates J. Ghromatogr. 109(1) 29-36 (1975) ... 

Adulterants and Diluents Adulterants and diluents added to a batch can provide useful information regarding batches and groups. Common adulterants in heroin are acetaminophen (referred to as paracetamol outside of the United States), caffeine, and lidocaine, all of which chromatograph well and can be detected simultaneously with the heroin. Diluents tend to be highly variable. Many are hard to identify during routine analysis, since some are removed in the sample preparation steps. Even if a dUuent can be isolated, its identification often requires more time than can be spared in routine cases. Sometimes a quick microscopic examination of residues is sufficient to identify starches... 

However, the small injection volume available to CE (a few nl) means that high sensitivity can only be achieved if concentrations of the analyte in the sample are high. Nevertheless, some results have been reported using CE-NMR and the method has been applied to the identification of paracetamol metabolites in human urine. Finally the application of capillary electrochromatography (CEC) directly coupled to NMR has been explored using the same paracetamol metabolite samples. 

The considerable commercial interest of the pharmaceutical industry in Paracetamol (Sopharma, Bulgaria), polymorphs, and their quantitative analysis, as a result of their wide usage as antipyretic and analgetic agents, has led to the development of suitable methods of characterization. X-ray diffraction (XRD), for example, is a powerful technique for the identification of a crystalline solid phase. IR spectroscopy is also a recommended method. 

Al-Zoubi, N., J.E. KoundoureUis, and S. Malamataris. 2002. FT-IR and Raman spectroscopic methods for identification and quantitation of orthorhombic and monocfinic paracetamol in powder mixes. J. Pharmaceut. Biomed. Anal. 29 459-467. 

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