Characterization of benzodiazepine drugs by ion mobility spectrometry.

Chemical ionization ion mobility spectrometry (CI-IMS) was used to characterize a number of benzodiazepines. In almost every example studied, the positive ion mobility spectrum consisted of a single ion peak corresponding to [M]+ or [MH]+. With some compounds, e.g., oxazepam, lorazepam, and chlordiazepoxide, fragment ions were noted that serve as good markers for the identification of these chemicals. Reduced mobility constants (K0) for the most significant peaks were calculated, and all ions produced were mass-analyzed by injection into a quadrupole mass spectrometer. The results of this study point to the potential of IMS as a qualitative tool for the rapid detection (analysis time less than 10 s) and reliable identification of benzodiazepines. Preliminary results on the application of digital signal processing and a second-derivative algorithm to partially overlapping IMS peaks are presented, and potential improvements are discussed.

Skin surface sampling for nicotine: a rapid, noninvasive method for identifying smokers.

We evaluated a novel, rapid, noninvasive method of skin surface air sampling that detects the presence of nicotine and therefore can identify smokers. The principle of the methodology involved is skin surface air sampling and ion-mobility spectrometry. We studied 93 volunteers and patients; 50 of these gave a positive history for smoking. Skin surface sampling identified 49 of these 50 individuals. Fifty of the 93 individuals provided urine samples. Nicotine was detected in 22 of these urine samples by thin-layer chromatography. Skin surface sampling identified all of these patients. The combination of skin surface air sampling and ion-mobility spectrometry is a rapid, noninvasive screening method for separating smokers from nonsmokers.

Ion mobility spectrometry and ion mobility spectrometry/mass spectrometric characterization of dimenhydrinate.

Positive and negative ion mobility spectra of dimenhydrinate are presented, and the calculated reduced mobility (K0) values for the most significant peaks are reported. Mass identification of the ionic species associated with the peaks in the ion mobility spectra was achieved by interfacing the ion mobility spectrometer to a mass spectrometer. The application of ion mobility spectrometry to the detection of dimenhydrinate and other drug residues on the hands of patients admitted to hospital with drug overdose is also discussed.

Detection of drugs in patients with overdose: comparison between skin surface air sampling and thin layer chromatography.

We compared the efficacy of skin surface air sampling with thin layer chromatography (TLC) in detecting drugs in patients admitted to hospital with a history of drug overdose. The methodology utilizes air samples in contact with skin surfaces and ion-mobility spectrometry. Fifty patients consented to skin surface air sampling and provided urine samples. Of the 51 drugs identified in 43 patients, air sampling detected just over 50% of the drugs, TLC identified about 90%. The rate of identification was greater in patients ingesting uncoated tablets. Skin surface air sampling is a useful initial screening method for drugs especially when they are ingested in tablet or powder form. The methodology is rapid, noninvasive and can screen for multiple drugs.

Detection of drug residues on the hands of subjects by surface sampling and ion mobility spectrometry.

This paper deals with the detection of drug residues on the hands of human subjects. The results demonstrate that detectable amounts of particulate matter are transferred to the hands by brief contact with drug tablets. A sampling and analysis method has been developed, and is based on the aspirating and trapping of drug microparticles on a filter plug, to be followed by thermal desorption directly into an ion mobility spectrometer. The technique is suited for initial field screening in clinical and forensic applications. The major drugs detected were diazepam, amitriptyline, codeine, acetaminophen, nitroglycerin, and delta 9-tetrahydrocannabinol (delta 9-THC).

Use of skin surface sampling and ion mobility spectrometry as a preliminary screening method for drug detection in an emergency room.

We have evaluated the use of a novel method for detecting drug residues on the hands of emergency patients suspected of drug overdose. The residues are collected by means of a suction probe and subsequently analyzed by thermal desorption directly into an ion mobility spectrometer. All patients admitted to the Emergency Room had their palms, fingers and nostrils sampled. Of the 101 drug related ingestions, 50 were related to tablets, 47 to film or sugar-coated tablets and 4 to cocaine powder. Positive identification was possible in 42% of tablet related ingestions, 29% of coated tablet or capsule ingestions and in all patients using cocaine. In 53% of the cases where positive drug identification was made, sampling had been carried out within 30 minutes of the patient's arrival at the Emergency Room.

Application of air sampling and ion-mobility spectrometry to narcotics detection: a feasibility study.

A feasibility study of the application of air sampling and ion-mobility spectrometry (IMS) for detection of heroin and cocaine concealed in letter mail showed that a unique IMS signature is associated with each type of drug and that a number of IMS peaks can be used as markers for the presence of drugs. No false reading for cocaine or heroin resulted when innocent items were monitored. Near real-time performance with sampling and analysis times of less than 30 seconds was achieved for the simultaneous detection of cocaine and heroin. The method proved to be a reliable tool for the fast screening of suspect items. Preliminary tests also showed that the method has potential for use in detecting the drugs in suitcases and on people.