A Study on Photostability of Amphetamines and Ketamine in Hair Irradiated under Artificial Sunlight

Abstract

Drugs incorporated into hair are exposed to the environment, and cosmetic and chemical treatments, with possible decreases in their content. Knowledge concerning the effect of sunlight on drug content in hair can be helpful to forensic toxicologists, in particular, when investigating drug concentrations above or below pre-determined cut-offs. Twenty authentic positive hair samples were selected which had previously tested positive for amphetamines and/or ketamine. Washed hair were divided into two identical strands, with the former exposed at 765 W/m2 (300–800 nm spectrum of irradiance) for 48 h in a solar simulator, and the latter kept in the dark. Hair samples were extracted and analyzed by liquid chromatography high-resolution mass spectrometry detection. The percentage of photodegradation was calculated for each analyte (i.e., amphetamine, methamphetamine, methylendioxyamphetamine, ketamine, and norketamine). In parallel, photodegradation processes of standard molecules dissolved in aqueous and organic solutions were studied. In 20 hair samples positive for the targeted analytes, exposure to artificial sunlight induced an appreciable decrease in drug concentrations. The concentration ranges in the non-irradiated hair samples were 0.01–24 ng/mg, and 65% of samples exhibited a decrease in post-irradiation samples, with reduction from 3% to 100%. When more drugs were present in the same hair sample (i.e., MDMA and ketamine) the degradation yields were compound dependent. A degradation product induced by irradiation of ketamine in aqueous and methanol solutions was identified; it was also found to be present in a true positive hair sample after irradiation. Ketamine, amphetamines, and their metabolites incorporated in the hair of drug users undergo degradation when irradiated by artificial sunlight. Only for ketamine was a photoproduct identified in irradiated standard solutions and in true positive irradiated hair. When decisional cut-offs are applied to hair analysis, photodegradation must be taken into account since sunlight may produce false negative results. Moreover, new markers could be investigated as evidence of illicit drug use.

Electrospun Nanofibrous Membrane-Based Colorimetric Device for Rapid and Simple Screening of Amphetamine-Type Stimulants in Drinks

“…The ratio of PVDF and PEO is the optimal condition for rapid and simple screening of ATSs in beverages. Also, nanofibers are expected to impart the DSKs with a high surface area-to-volume ratio and high porosity, thus enabling rapid detection of ATS as well as improving the detection sensitivity. ,,− Also, this process enables mass production of DSKs. As most of the organic solvent (NMP and acetone) was volatilized during electrospinning, nanofiber sheets were obtained on the collector. − After UV irradiation, the white-colored nanofiber sheets turned blue, indicating that PDA nanofibers were formed by the polymerization of the self-assembled DA monomers in these sheets.…”

“…Many technologies, including mass spectrometry, infrared spectrometry, Raman spectroscopy, X-ray diffractometry, thin-layer chromatography (TLC), ultraviolet spectroscopy, immunoassays, urine dipstick tests, and spot/color tests, have been developed for drug testing. − In particular, mass spectrometry-based technologies such as liquid chromatography–mass spectrometry, gas chromatography–mass spectrometry, and matrix-assisted laser desorption/ionization mass spectrometry enable the qualitative and quantitative analysis of drugs with high resolution. − These techniques are commonly applied in forensic drug analysis. In addition, various indicators, such as cobalt nitrate, oxammonium chloride/ferric chloride, saturated potassium dichromate, toluene/cobalt thiocyanate, and chromium­(IV) oxide/sulfuric acid carbodiimide salts, have been developed that chemically react with illegal drugs, causing a specific color depending on the drug. , These drug screening techniques are effective for the highly sensitive detection of trace amounts of drugs in biological samples (blood, urine, hair, sweat, and exhaled breath). ,,,− ,− That is, these techniques are focused on postconsumption detection to determine whether a person is taking or has taken drugs. Furthermore, these technologies require specific instrumentation with skilled operators and are time-consuming, with results obtained in seconds to minutes or minutes to hours.…”

Effects of temperature, humidity, light, and soil on drug stability in hair: a preliminary study for estimating personal profiles using micro-segmental analysis of corpse hair

“…Since sunlight consists of light with a wider wavelength and higher intensity than the artificial light used in this study, various lights can cause complex damage to hair tissues. Miolo et al previously reported that amphetamines and ketamine levels decreased in hair irradiated with artificial sunlight [ 31 ]. The degradation yields depended on the compounds, light conditions, and hair properties.…”

Alternative matrices in forensic toxicology: a critical review

“…These treatments, associated with continuous exposure to natural factors such as sunlight, weather and pollution can contribute to increase the damage in the hair cuticle [64]. In particular, photodegradation of drugs through the formation of free radicals or photosensitization reactions by intermolecular energy transfer can occur when the hair is exposed to sunlight or artificial light for many hours per day [65].…”