Morphine-3-D glucuronide stability in postmortem specimens exposed to bacterial enzymatic hydrolysis.

Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths.

Analysis of succinylcholine in tissues and body fluids by ion-pair extraction and gas chromatography-mass spectrometry.

The neuromuscular blocking agent succinylcholine (SCh) has been identified and quantitated in biological material using gas chromatography-mass spectrometry. The bisquaternary ammonium compound SCh is extracted from tissue homogenates or body fluids into dichloromethane as an ion pair with hexanitrodiphenylamine (DPA). The evaporated ion pair residue is demethylated with sodium benzenethiolate to form the corresponding tertiary amine which is identified and quantitated by gas chromatography-mass spectrometry using a glass capillary column coated with SE 52. In the quantitative analysis deuterated SCh is used as internal standard. The instrument is focussed on m/z 58 for demethylated SCh and m/z 62 or 64 for the internal standard. Concentrations as low as 5 ng SCh iodide/g tissue or body fluid are easily detected.

Extraction, identification and quantitation of succinylcholine in embalmed tissue.

Succinylcholine, a bis-quaternary ammonium compound, was extracted from embalmed tissues as an ion-pair with hexanitrodiphenylamine in methylene chloride. The evaporated ion-pair residue is demethylated with sodium benzenethiolate. The tertiary amine formed is identified and quantitated by gas chromatography/mass spectrometry (GC/MS) utilizing a 25 meter glass capillary column coated with SE 52. Identification is accomplished by retention time and mass spectrometry. Quantitation is performed after the addition of deuterated succinylcholine as an internal standard by focusing the mass spectrometer on m/z 58 (for demethylated succinylcholine) and m/z 62 (for the internal standard). The method is applied to the quantitation of succinylcholine from the embalmed kidney, liver, and muscle of rats injected i.m. with 10-200 mg/kg. After six months of storage, the succinylcholine can still be identified and quantitated with highest concentrations found in the muscle injection site. Concentrations as low as 5 ng/g are easily detected.

Smoking and warfarin disposition.

Nine cigarette smokers ingested an average daily 0.032 mg/kg dose of sodium warfarin for 2 wk while continuing to smoke and for an additional 2 wk after having abstained from cigarette smoking for a month washout phase. Steady-state plasma levels of warfarin, clearances, t 1/2, apparent volumes of distribution, steady-state prothrombin times, and plasma thiocyanate levels were measured during both the smoking and nonsmoking phases. During the nonsmoking phase there was a 13% increase in average steady-state warfarin level and a 13% decrease in warfarin clearance rate. There also was a 23% increase in warfarin t 1/2 and an 11% increase in the apparent volume of distribution. Prothrombin time did not change. Thiocyanate levels were 3 to 4 times as high during the smoking than the nonsmoking phase. It appears that cigarette smoking does affect warfarin clearance, t 1/2, and apparent volume of distribution, though the net effect on warfarin's pharmacodynamic activity is negligible, at least at doses which are ineffective therapeutically.