Study regarding drugs in blood with ELISA and chemiluminiscence versus ELISA with spectrophotometric detection

Biochip Array Technology (BAT) is a new technique used for screening purposes in clinical and forensic toxicology. The purpose of this article is to compare it with the standard ELISA with spectrophotometric detection (SD) in regard of its sensibility and specificity. Material and methods. Fifty five samples were analyzed on both BAT and ELISA SD; the results were confirmed using either GC-MS (for opiates, benzoilecgonine and cannabinoids) or HPLC (for barbiturates and benzodiazepines). Results. For opiates BAT technique had a sensibility of 100% and a specificity of 97.72%. Sensibility for ELISA SD technique was 92.3% and specificity 97.72%. For benzoilecgonine the sensibility and specificity for BAT was 100% whilst for ELISA SD the sensibility was 100% and specificity was 93.10%. For cannabinoids the sensibility for BAT was 90%, and specificity was 97.7% whilst for the ELISA SD technique the sensibility was 100% and the specificity was 91.11%. For barbiturates the sensibility and specificity was 100% for both methods. For benzodiazepines the sensibility for BAT was 100% and the specificity was 95.65% whilst for ELISA SD the sensibility was 100% and the specificity was 93.47%. Conclusions. The results obtained on BAT are comparable with those from ELISA-SD and have a high sensitivity and specificity compared to the used confirmatory methods. The results do not have however an increased statistical significance due to a very small number of positive results, caused by an abruptly decreasing number of positive cases in the last year, mainly due to increased used of "legal highs".