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Investigation into the suitability of capillary tubes for microcrystalline testing: Capillary tubes for microcrystalline tests

Elie, Leonie E.; Baron, Mark G.; Croxton, Ruth S.; Elie, Mathieu P.

Authors

Leonie E. Elie

Mark G. Baron

Mathieu P. Elie



Abstract

A comparison between microcrystalline tests performed on microscope slides and flat capillary tubes with inner diameters ranging from 0.1 to 0.7 mm was carried out to explore the appropriateness of tubes for rapid testing of suspected drugs of abuse in the laboratory as well as in the field. Tests for mephedrone, cocaine and phencyclidine were chosen as examples to investigate the handling of the capillary tubes, the influence on crystal habit, size and the effects on the limit of detection. Image stacking software was used to increase the depth of field of micrographs taken from developed microcrystals greatly enhancing the interpretability even
months after carrying out the microcrystalline test. Additionally, the potential of seeding capillary tubes with a reagent was studied. Pretreatment of tubes would allow microcrystalline tests to be carried out quicker and anywhere without the necessity of taking along expensive and hazardous reagents. The sealing of capillary
tubes containing developed microcrystalline tests in order to preserve results for a long period of time was successfully done by applying paraffin wax to the open ends. Finally, it was concluded that capillary tubes are suitable vessels for performing microcrystalline tests. The increased portability of the improved set-up allows tests to be safely executed outside laboratories without impairing the quality of the result. Findings were applied to six legal high samples purchased online between May and August 2011. The active ingredients like MDAI as well as cutting agents like caffeine were successfully identified using the microcrystalline test technique in capillary tubes.

Journal Article Type Article
Publication Date 2013-07
Journal Drug Testing and Analysis
Print ISSN 1942-7603
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 5
Issue 7
Pages 573-580
APA6 Citation Elie, L. E., Baron, M. G., Croxton, R. S., & Elie, M. P. (2013). Investigation into the suitability of capillary tubes for microcrystalline testing: Capillary tubes for microcrystalline tests. Drug Testing and Analysis, 5(7), 573-580. https://doi.org/10.1002/dta.1372
DOI https://doi.org/10.1002/dta.1372
Keywords Analytical Chemistry; Spectroscopy; Pharmaceutical Science; Environmental Chemistry
Publisher URL https://onlinelibrary.wiley.com/doi/abs/10.1002/dta.1372
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