Fully Automated Forensic Routine Dried Blood Spot Screening for Workplace Testing

Abstract

In this study we describe the transfer of a new and fully automated workflow for the cost effective drug screening of large populations based on the dried blood spot (DBS) technology. The method was installed at a routine poison control center and applied for DBS and dried urine spot (DUS) samples. A fast method focusing on the high interest drugs and an extended screening method were developed on the automated platform. The dried cards were integrated into the automated workflow, in which the cards were checked in a camera recognition system, spiked with deuterated standards via an in-built spraying module and directly extracted. The extract was transferred online to an analytical LC column and then to the electrospray ionization tandem mass spectrometry system. The target compounds were analyzed in positive multiple reaction monitoring mode. Before each sample batch or analysis day, calibration samples were measured to balance inter day variations and to avoid false negative samples. An internal standard was integrated prior the sample extraction to allow in process control. 28 target compounds were analyzed and directly extracted within 5 minutes per sample. This fast screening method was then extended to 20 minutes, enabling the usage of a Forensic Toxicology Database to screen over 1200 drugs. The method gives confident positive/negative results for all tested drugs at their individual cutoff concentration. Good precision (+/-15 %, respectively +/-20 % at LOQ) and correlation within the calibration range from 5 to 1000 ng/ml was obtained. The method was finally applied to real cases from the lab and cross checked with the existing methodologies.

Do dried blood spots (DBS) have the potential to support result management processes in routine sports drug testing?

“…A conceivable alternative in this context have become dried blood spot (DBS) matrices, which are readily produced, comparably cheap, and which offer stabilizing features for the target analyte. 14 In combination with recent advances in sampling techniques, (semi-)automated DBS sample preparation options, [15][16][17][18] and the considerably enhanced instrumental sensitivity in bioanalysis, the collection of matched pairs of urine and DBS samples in routine doping controls would offer a substantial added value for the wider overview on the testing.…”

Fully automated dried blood spot sample handling and extraction for serological testing of SARS‐CoV‐2 antibodies

“…The samples were previously assessed for IgG using serological rapid testing (GreenCheck two‐stage rapid test GC2019 nCoV) from Protzek (Lörrach, Germany) and an assessment for COVID symptoms by a questionnaire. The DBS cards were loaded into the DBS‐MS 500, and the sample batch and sample processing were programmed within the Chronos for CAMAG software, see Table 1 12,13 . The samples were extracted (4.2‐mm diameter, sub‐punch from the center of the spot), within 2 min per sample, directly into a 96‐well plate using 100 μl of buffer contained within the Epitope ELISA kit.…”

“…The DBS cards were loaded into the DBS-MS 500, and the sample batch and sample processing were programmed within the Chronos for CAMAG software, see Table 1. 12,13 The samples were extracted (4.2-mm diameter, sub-punch from the center of the spot), within 2 min per sample, directly into a 96-well plate using 100 μl of buffer contained within the Epitope ELISA kit. Additionally, for a subset of samples, the impact of different wash buffers was investigated by pre-cleaning the sub-spot before the actual extraction (extraction of the sub-spot with a wash buffer, followed by the extraction with…”

What the lab can and cannot do: clinical interpretation of drug testing results

“…Recent advancements to address the effect of HCT include collecting and depositing a fixed volume of blood, regardless of the blood HCT, and analyzing the entire sample rather than a sub-aliquot (sub punch) [60]. The advantages of DBS technology are that it can be automated and is not restricted to blood samples but can also be applied to other matrices such as dried serum, urine, and saliva spots [61][62][63].…”