Quantification of cocaine and its adulterants by nuclear magnetic resonance spectroscopy without deuterated solvents (No-D qNMR)

Abstract

A new analytical method was developed to quantify cocaine and some adulterants using nuclear magnetic resonance spectroscopy without the use of deuterated solvents.

Analysis of Erythroxylum coca Leaves by Imaging Mass Spectrometry (MALDI–FT–ICR IMS)

“…Among them, the most abundant compound in the mass spectrum is the cocaine alkaloid, detected as the protonated ion, [C 17 H 21 NO 4 + H] + , of m / z 304.15420, with signal resolution = 517.670, error = 0.43 ppm, and DBE = 8 (due to its aromatic ring (4), the CO bond of the two ester groups (2), and the tropane nucleus (2)). This result is similar to those reported by other authors, which indicate a greater abundance of this alkaloid compared to the others in the plant. , …”

“…This result is similar to those reported by other authors, which indicate a greater abundance of this alkaloid compared to the others in the plant. 18,32 In contrast, the analysis of the coca leaf using the LDI(+) MS source, Figure 1b, with direct desorption and ionization of compounds (UV laser at 355 nm), resulted in the detection of abundant cocaine, in the form of the adduct with potassium, [C 17 H 21 NO In general, the LDI(+) and MALDI(+) techniques operate by laser incidence; 5 however, in this study, the cocrystallization of the matrix with the analyte, that is, MALDI(+), provided an increase in sensitivity when compared with the LDI(+) MS technique. This performance is evaluated using the values of the total ion current (TIC): TIC LDI: [Coc+K] + = 3.2 × 10 6 and TIC MALDI: [Coc+H] + = 1.5 x10 7 .…”

“…The Erythroxylum coca plant, found mainly in South America, is chemically characterized by tropane alkaloids. − In general, more than 150 tropane alkaloids, which have in common a structural element, the azabicyclo[3.2.1]­octane system, have been isolated from different plants. , Among them, the main and most abundant alkaloid, detected in some species of Erythroxylum , is cocaine (methyl (1 S ,3 S ,4 R ,5 R )-3-benzoyloxy-8-methyl-8-azabicyclo­[3.2.1]­octane-4-carboxylate, M = C 17 H 21 NO 4 ; M w = 303.4 Da; melting point 96–98 °C, and pKb = 5.4). − …”

Isolation and characterization of reference standard candidates for cocaine and benzoylecgonine obtained from illicit substances seized

“…Methyl(1S,3S,4R,5R)-3-benzoyloxy-8-methyl-8-azabicyclo [3.2.1] octane-4-carboxylate, commonly known as cocaine, is a tropane alkaloid extracted from the leaves of Erythroxylum coca L. [1][2][3][4][5][6]. This alkaloid, a central nervous system stimulant [7], was isolated around 1860 by the German chemist Albert Niemann [8].…”

The influence of lateral flake size in graphene/graphite paste electrodes: an electroanalytical investigation

“…Current methods utilised for the determination of cocaine and amphetamines include powerful but complex equipment and require experienced experimentalists; such as, chromatography-tandem mass spectrometry (LC-MS and GC-MS), [28][29][30][31] spectrouorimetry 32 and nuclear magnetic resonance spectroscopy (NMR). 33 Although these analytical techniques are sensitive, reliable and precise, they do however require expensive instrumentation, are labour intensive (extensive sample preparation) and thus are not available in all laboratories for routine analysis. 34,35 Consequently, low cost and portable electrochemical platforms can be easily integrated into in-the-eld hand-held devices to be used by health/law enforcement offering high sensitivity, good selectivity, signicantly faster analysis and reasonable prices.…”