Development and Validation of a Sensitive LC-MS/MS Method for the Simultaneous Analysis of Three-Tropane Alkaloids in Blood and Urine

Analysis of scopolamine and its related substances by means of high-performance liquid chromatography

The retention behaviour of scopolamine (hyoscine) and its related compounds (norhyoscine, atropine, homatropine, and noratropine) was investigated on the silica-based HPLC stationary phase. The retention of investigated tropane alkaloids was interpreted by using the Soczewiński-Wachtmeister equation. A high correlation between the retention parameter (log k) and lipophilicity (log P) (R = 0.9923) confirms the significant influence of hydrophobic interactions on the retention behaviour of the aforementioned compounds. It was found that by increasing the acetonitrile fraction, a decrease in retention of the more polar epoxide derivatives (scopolamine, norhyoscine) and an increase in retention of the more lipophilic derivatives (atropine, noratropine, homatropine) is obtained. The best separation of the tropane alkaloids was achieved by a simple procedure that involved a mobile phase composed of acetonitrile and 40 mM ammonium acetate/0.05% TEA, pH 6.5; 50:50 v/v. Selected conditions were assumed for the determination of scopolamine hydrochloride in the eye drops (Scopolamini hydrobromidum 0.25%). The method was validated and it was found as selective, sensitive, precise, accurate, and robust for the further qualitative analysis of the scopolamine-related compounds.

A validated LC-MS/MS method for the determination of L-hyoscyamine in human plasma: Application in clinical study

Atropine is a racemic mixture of D- and L-hyoscyamine, while L-hyoscyamine is the only effective ingredient. In this study, a new sensitive, stable, and selective LC/MS assay was developed for determination of L-hyoscyamine and applied to the clinical study. The parent-product (m/z) transition pair of L-hyoscyamine was 290.1→124.1. Chromatographic separations were performed using a Chiral MZ column (250 mm×4.6 mm, 5.0 μm) by a stepwise gradient elution mode with n-hexane, isopropanol and diethylamine as mobile phases. L-hyoscyamine in human plasma were extracted using liquid-liquid extraction process. This assay displayed a good linearity over a concentration range of 20.0-400 pg/mL for L-hyoscyamine. The accuracy of the validation assay for L-hyoscyamine ranged from -2.7% to 4.5%, and the precision were within 6.3% coefficient of variation. L-hyoscyamine in human plasma were stable at different storage conditions. The method has been successfully applied to plasma samples obtained from a safety study in human.

Application of a streamlined LC-MS/MS methodology for the determination of atropine and scopolamine in cereals from Asian and African countries

Tropane alkaloids are toxic secondary metabolites produced by a wide variety of plants that can be present in edible materials or animal feed. Several human poisoning cases through consumption of cereals were reported over the last years and highlighted the need for reliable and robust analytical methodologies for safety control. To rationalize analyses in high-throughput laboratory environments dealing with shorter and shorter turn-around-around time, the scope of our multi mycotoxins method was extended to the analysis of two regulated tropane alkaloids, namely atropine and scopolamine. Extraction procedure is based on the QuEChERS (Quick, Easy, Cheap, Efficient, Rugged, and Safe) approach followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) detection. Quantification is performed by the isotopic dilution approach using labelled isotopomers as internal standard. The procedure was validated at two fortification levels (0.5 µg/kg and 10 µg/kg) on different cereal-based products according to the European SANTE/12682/2019 document and performance parameters such as precision (RSD(r) ≤ 6%, RSD(iR) ≤ 6%) and recovery (82-114%) fulfilled its requirements. The limit of quantification (0.5 µg/kg) is low enough to ensure compliance with existing regulations. The method was further applied on 95 cereals and cereal-based products collected from Asian and African countries. All samples were found free of the two targeted TAs, with the exception of a rice-based product in which both atropine and scopolamine were quantified at 9.6 µg/kg and 2.6 µg/kg, respectively. A total of 29 cereals samples, shown to be free of both atropine and scopolamine were also analysed for mycotoxins. Aflatoxins, fumonisins, and deoxynivalenol were sporadically detected at levels below the maximum levels defined by the European Union legislation often considered as the most stringent regulation.