GC‐MS analysis of multiply derivatized opioids in urine

Abstract

Opiates such as hydrocodone, hydromorphone, oxycodone, noroxycodone, and oxymorphone reportedly may interfere with the analysis of morphine and codeine. The analysis of these compounds themselves also is an important issue. Thus, double derivatization approaches utilizing methoxyamine and hydroxylamine to first form oxime products with keto-opiates, followed by the derivatization with trimethylsilyl (TMS) or propionyl groups, have been developed for the simultaneous analysis of these compounds. However, these studies have not included all compounds of interest and resulted in inadequate chromatographic resolution or significant intensity cross-contribution between the ions designating the analyte and its deuterated internal standard for certain compounds. By exploring three-step derivatization approaches with the combination of various derivatization groups and orders, this study concluded that application of methoxyimino/propionyl/TMS groups, in the order listed, facilitated the simultaneous analysis of eight opiates (morphine, 6-acetylmorphine, hydromorphone, oxymorphone, codeine, hydrocodone, oxycodone and noroxycodone) in urine samples, achieving satisfactory limits of quantitation and detection. In addition, the adapted approach resulted in two usable products for morphine and codeine providing alternatives, should interferences render any of these products non-usable.

Derivatization Reactions and Reagents for Gas Chromatography Analysis

“…Replacement of active h y d r o g e n b y a s i l y l group reduces the polarity of the compound and reduces hydrogen bonding (Pierce, 1968). Many hydroxyl and amino compounds regarded as nonvolatile or unstable at 200 -300 °C have been successfully analyzed in GC after silylation (Lin et al, 2008& Chen et al, 2007. The silylated derivatives are more volatile and more stable and thus yielding narrow and symmetrical peaks (Kataoka, 2005).…”

Chemometric approach for development, optimization, and validation of different chromatographic methods for separation of opium alkaloids

“…The method required no prior derivatization of the components, which launched the main advantage regarding most of the published methods [17][18][19][20][21][22]. The chromatographic conditions, such as injector temperature (190,210,230,250,270, and 290°C), initial column temperature (100, 150, 180, 200, and 220°C), final column temperature (290, 300, and 310°C), initial temperature hold time (0.5, 3, and 5.5 min), column temperature rate (20, 30, 40°C/min), and carrier gas flow rate (1.0, 1.5, и 2.0 ml/min) were all optimized.…”

“…Gas chromatography (GC) is the method of choice for bioanalysis of opium alkaloids [14][15][16][17][18][19][20][21][22], but for the analysis of the plant extracts may be less convenient due to the many less volatile substances co-extracted [9]. The major constrain of the GC methods is the commonly used prior derivatization of the analytes in order to volatilize them, avoid broadening of the peaks in order to achieve easier quantification.…”

Sample preparation and separation techniques for bioanalysis of morphine and related substances

“…An example of a fully automated LC method using column switching has been developed [53]. Urine analysis is however less often performed unless it is in connection to the verification of drug abuse and a number of forensic, doping and other laboratories perform such analysis routinely either by LC-MS [54,] or by GC-MS [55]. Many of the methods are similar to those used for analysis of saliva (Section 2. new MS technique involving surface analysis -desorption ESI (DESI) -has been shown to give results equivalent to GC-MS analysis [56].…”