Detection of abused drugs in human blood by using the on-site drug-screening device Oratect® III

•A simple and precise drug screening method in blood was developed by Oratect® III.•The drugs in blood was extracted by the ultrafiltration column Vivaspin 2 Hydrosart®.•This method can be detected the concentration for the therapeutic level.•The proposed method is useful to screen for drugs of abuse in forensic laboratories.

A simple and precise drug screening method was developed for the detection of abused drugs in whole blood by using the Oratect® III device that is usually employed for the detection of drugs in saliva. Whole blood was acidified with phosphoric acid, following which the hemolyzed solution was filtered through the ultrafiltration column Vivaspin 2 Hydrosart®. The filtrate was then tested for the presence of drugs using Oratect III. The detection limit of the device for methamphetamine, amphetamine, morphine, codeine, dihydrocodeine, diazepam, alprazolam, estazolam, and prazepam in whole blood was 125, 125, 50, 50, 50, 25, 60, 15, and 75 ng/mL, respectively. The concentration range detected was between therapeutic and toxic drug levels; therefore, the proposed method can be applied for detecting the presence of abused drugs in blood. Our method is a novel, optimized technique for use in forensic laboratories to screen whole blood for drugs of abuse.