Infrared attenuated total reflection (IR-ATR) spectroscopy for detecting drugs in XXXX saliva.

@entity1 @entity2072 @entity285
The consumption of drugs is of great concern worldwide. Various drug tests for @entity1 have been developed but there is no compact and easy-to-use test device available yet for direct semi-quantitative drug testing in the field. We suggest using attenuated total reflection (ATR) infrared spectroscopy as a sensing method to analyze @entity1 saliva samples with respect to drugs. In this paper, we present ATR spectra in the infrared range between 2300 and 900 cm(-1) as a first step towards such a device. We emphasize the common drug @entity2072 and its metabolites and investigate the problems of spectral interferences of selected diluents, masking agents, common medication, and soft drinks. Furthermore, spectra of saliva samples are recorded and a time-dependent change of the spectral signatures after @entity285 consumption is presented. To the best of our knowledge, it is the first time that not only spectra of the drug of interest ( @entity2072 ) dissolved in water and in saliva but also spectra of interfering compounds possibly present in the saliva sample of a tested subject are discussed. This paper presents the most appropriate spectral range for strong @entity2072 absorption (including its metabolites) and minimum interference by the investigated substances. This spectral window is found to be between 1800 and 1710 cm(-1). In addition, we demonstrate the feasibility to identify @entity2072 in saliva at a concentration of 0.020 mg/ml with IR-ATR-spectroscopy without any separation or extraction procedures. For example, this technique could also be applied for drug detection in waste water.
