Earwax as an alternative specimen for forensic analysis

Abstract

In this work, we presented, for the first time, earwax as an alternative forensic specimen for detecting 12 neuropsychotic drugs employing liquid chromatographytandem mass spectrometry in positive and negative ion modes after straightforward extraction with methanol. The method was validated and standard curves were established by external calibration with correlation coefficients [0.99. All precision, accuracy, matrix effects, extraction recoveries, and carryover were within acceptable limits; limits of quantification were sufficiently low to quantify almost all the samples tested. To confirm the feasibility of the study, earwax specimens were collected from actual patients treated with different combinations of the 12 drugs and analyzed by our method; the 12 drugs could be quantified from the earwax specimens of the users successfully, showing usefulness of earwax specimens, because of its noninvasive sampling and the storage of drug(s) for relatively long time together with its being relatively less contaminated by environmental impurities. This study is pioneering; many detailed studies on earwax as an alternative specimen remain to be explored.

Insights into cerumen and application in diagnostics: past, present and future prospective

“…On the other hand, earwax was most recently used as a medium for monitoring drugs specially to indicate administration of drugs of abuse or drug facilitated crimes antiepileptics, anxiolytics, antipsychotics, etc. Cerumen could be even considered a more favourable surrogate to traditionally used biological fluids because of its non-invasiveness, ease of sample collection, minimum sample pretreatment, and relatively less external contamination in addition to being able to detect the analytes recently administered as well as drugs administered some months ago ( 78 ).…”

A volatolomic approach using cerumen as biofluid to diagnose bovine intoxication by Stryphnodendron rotundifolium

“…In humans, our recent studies demonstrated that cerumen could be used to diagnose types I and II diabetes mellitus (Shokry, de Oliveira, Avelino, de Deus, & Filho, 2017). In addition, cerumen can be used for tracking human exposure to tobacco (Shokry, de Oliveira, Avelino, de Deus, Pereira, et al, 2017), as an alternative biomatrix to forensic applications for drug abuse monitoring (Shokry, Marques, Ragazzo, Pereira, & Filho, 2017), and for cancer diagnosis (Barbosa et al, 2019). In animals, the volatile cerumen compounds have been used to detect the toxic principle in cattle intoxication by Palicourea marcgravii (Shokry, dos Santos, et al, 2017) and to assess disorders in sheep in peri‐parturition stage (Shokry, Pereira, et al, 2017).…”

Cerumenogram: a new frontier in cancer diagnosis in humans

“…Recently, our research group successfully used cerumen VOMs to diagnose diabetes mellitus (DM) and differentiate between DM type I and II 29 . We have also investigated the viability of cerumen to diagnose intoxications and metabolic alterations in animals 25,30 , as well as for forensic applications as a monitoring biomatrix for drug abuse analysis 31 .…”