Ketamine detection

In the ED setting, the diagnosis of ketamine intoxication is a clinical one. Ketamine is not routinely detected by urine toxicology tests, although it can be detected with high-performance liquid chromatography (Koesters et al. 2002). As with MDMA, the initial assessment for ketamine intoxication includes the use of routine laboratory tests to detect electrolyte abnormalities and to evaluate renal and hepatic functioning (Koesters et al. 2002). 

Ketamine, a general anesthetic producing hallucinations and exhibiting an addiction potential, and norketamine have been determined in urine using SPE combined with RPLC-ESI(+)-MS-MS [49]. Cheng and Mok [49] developed a fast HPLC-MS-MS method able to separate and detect ketamine in a 2.5 min chromatographic run with a LOD of 5ng/mL. The method was applied to routine ketamine urine screening to a maximum of 200 samples per day. 

In addition, biochemical alterations are detectable in cisternal cerebrospinal fluid (CSF) samples obtained from ketamine-anesthetized unpre-... 

H. A. Adams, B. Weber, M. B. Bachmann, M. Guerin, and G. Hempelmann, The simultaneous determination of ketamine and midazolam using high pressure liquid chromatography and UV detection (HPLC/UV), Anaesthesist, 47 619 (1992). 

Ketamine is a compound with a molecular structure similar to that of phencyclidine (Figure 4.2). The pharmaceutical versions of ketamine are clear, colorless liquids available in varying concentrations of 10,50, and 100 milligram/milliliter solutions (Figure 4.3). Many recreational users inject this liquid intramuscularly or intravenously. It is the liquid formulation that is used as a date rape drug. Liquid ketamine, which is clear and colorless, can easily be slipped into a drink without being detected. 

The mechanism of PCP and ketamine action involves antagonism of a subset of receptors for the excitatory amino acid glutamate (Balazs et al., 2006). PCP is absorbed rapidly after smoking or injection, with peak blood concentrations noted 5-15 minutes after smoking. In contrast, peak concentrations are reached wo hours after oral administration. The drug remains in the system unmetabolized for more than nvo days, and PCP is detectable in urine for several weeks after a single use (Hawks Cliiang, 1986). 

Sams R, Pizzo P 1987 Detection and identification of ketamine and its metabolites in horse urine. Journal of Analytical Toxicology 11 58-62 Sarazan R D, Starke W A, Krause G F et al 1989 Cardiovascular effects of detomidine, a new U2-adrenoceptor agonist, in the conscious pony. Journal of Veterinary Pharmacology and Therapeutics 12 378-388... 

Called the "Drink Detective," it is a matchbox-sized drink testing kit that can detect three of the most common date rape drugs that sexual predators slip into drinks GHB, ketamine, and Rohypnol. The kit contains test pads for each of the three drugs, as well as pipettes for applying drops of a drink to the pads. For the first time, people going to bars, raves, or clubs could test their drinks for date rape drugs. 

Qualitative urine screening for PCP is widely available. PCP analogs may not be detected on routine screening, although they can cross-react in some immunologic assays (see Table 1-33, p 43). Ketamine is not detected on routine screening. 

Another study in healthy subjects using various experimental pain models found that ketamine antagonised the respiratory depressant effect of remifentanil. Remifentanil alone produced analgesic effects with all pain tests, but ketamine only enhanced the effect of remifentanil on intramuscular electrical stimulation. Acute remifentanil-induced hyperalgesia and tolerance were detected only by the pressure pain test and were not suppressed by ketamine. The combined effects of remifentanil and ketamine probably depend on the type of pain. ... 

Screening for a group of illicit drugs, so-called club drugs, rape drugs, or party drugs, was carried out with a dual-mode ITMS. The reduced mobility values of ketamine, GHB (gamma-hydroxybutyrate), ephedrine, flunitrazepam, methamphet-amine, MDA (3,4-methylenedioxyamphetamine), amphetamine, Amph-sulfate, and MDMA were reported, and the preferred mode of detection was noted. 

Fig. 3 Separation and determination of the enantiomers of ketamine in human plasma by using weak affinity chromatography and a column containing Oj-acid glycoprotein as the stationary phase with detection by mass spectrometry.

Severe chronic pain is sometimes treated with co-administered ketamine/ bupivacaine. These compounds were isolated from plasma and analyzed on a cyanopropyl column (A = 215nm). A 718/220/80/2 water (lOmM NaH2p04 buffer at pH 2.34)/methanol/acetonitrile/H3P04 mobile phase generated baseline separation in <8 min. The peaks were quite tailed. Introduction of TEA and/or a TFA/triethylamine buffer syston in place of the phosphate system may remedy this. Calibration curves from 10 to 400ng/mL (ketamine) and 125 to 4000ng/mL (bupivacaine) were stated, with the lowest concentration serving as the quantitation limit. Detection limits (S/N = 4) of 1 ng injected and 0.8 ng injected, respectively, were reported [563]. 

Cocaine, and its metabolites (benzoylecgonine, benzoylnorecgonine, norcocaine, bupivarcaine [internal standard]) were baseline resolved and separated from acepro-mazine, ketamine, and atropine [853]. A Cg column (2 = 215nm or 235 nm) and a 96.75/3.25/0.0025 water (2.5 mlM phosphate buffer at pH 2.75)/THF/TEA mobile phase gave complete elution in 25 min. Samples extracted from serum gave detection... 

Complications of drug analysis were successfully resolved by the combination of TLC with MALDI-MS. TLC combined with MALDI-MS was used for analysis of psychotropic drugs (3,4-methylenedioxy methamphetamine, 4-hydroxy-3-methoxy methamphetamine, 3,4-methylenedioxy amphetamine, methamphetamine, p-hydroxy methamphetamine, amphetamine, ketamine, caffeine, chlorpromazine, triazolam, and morphine) in biological samples [42]. This technique was able to analyze 3,4-methylenedioxy methamphetamine (MDMA) and its metabolites in urine samples without sample dilution, and the detection limit of the MDMA spot was 0.05 ng/ spot. Crecelius and coworkers described the use of TLC with MALDI-MS/MS for the structural analysis of small drug molecules [43]. This method was successfully applied to analyze two representatives of nonsteroidal antiinflammatory drugs (tenoxi-cam and piroxicam), and pharmaceutically active compound UK-137,457 and one of its related substances UK-124,912. The feasibility of UTLC-atmospheric pressure (AP)-MALDI-MS was described for the analysis of small molecules (triazole, midazolam, verapamil, and metaprolol) [44]. The authors compared the selectivity and sensitivity between UTLC- and HPTLC-AP-MALDI-MS. It was observed that UTLC plates provided 10-100 times better sensitivity in MALDI analysis than the conventional... 

Rapid Gas Chromatographic Analysis of Plasma Levels of Ketamine and Major Metabolites Employing Either Nitrogen Selective or Mass Spectroscopic Detection... 

UHPLC-QTOF MS has been successfiilly applied to urban wastewater in order to investigate the presence of illicit drags. Previous positives of MDMA, cocaine, benzoylecgonine, and norbenzoylecgonine found by triple quadrapole LC-MS/MS have been confirmed and other nonpreselected compounds, like ketamine or codeine, have been detected by reexamining MS data after MS acquisitions. 

Drugs employed have sedative or hypnotic properties with a rapid onset and induce memory loss during the period when the drug is active. The most-prevalent drugs detected, apart from alcohol, are the benzodiazepines and h5 notics (zolpidem and zopiclone). A wide range of other drugs, such as GHB, ketamine, sildenafil, methadone, buprenorphine, diphenhydramine, trimeprazine, acepromazine, thiopental, pentobarb, doxylamine, and cyamemazine, have also been reported in DFC cases. 

In our experiments, we have tried to detect if ketamine thiopentaP or... 

An assay for ketamine was described by Feng et al. [18]. The ion-trap detector, used by these authors, confines ions in the ionization chamber before expelling them, which induces ion molecule reactions. The spectra obtained in this way are often different from conventional El spectra. For the ketamine, for instance, which should show a molecular ion at m/z 237, an unexpected [M -I-1] ion at m/z 238 is observed. This artifact appears to result from Cl, but in the present case it permits a specific detection of ketamine. The linearity ranges from 25 to 250 ng/ml and the yield of recovery was very good and in an acceptable concentration range. 

Also the metabolite dehydronorketamine has a longer duration time in urine than its precursor ketamine and the other metabolite norketamine. Dehydronorketamine can be detected after 7-10 days from the consumption of a modest dose of ketamine and is therefore a very useful diagnostic metaboUte. 

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