Preclinical Validation of an Electrochemical Sensor for Alcohol Consumption Monitoring in a Polydrug Self-Administration Animal Model

An electrochemical sensor for identification and monitoring of alcoholism was preclinically validated by analyzing plasma from polydrug-consuming rats (alcohol and cocaine). The sensor measures by adsorptive transfer square wave voltammetry the glycosylation level of transferrin, which is an alcoholism biomarker, through a recently reported parameter called the electrochemical index of glycosylation (EIG). Three rat groups were designed: saline group, cocaine group, and cocaine–alcohol group. Moreover, two periods of withdrawal were studied, after 2 days and 30 days. The alcohol–cocaine group after 2 days of withdrawal showed significantly lower EIG values (p < 0.1) than the rest of groups and also alcohol–cocaine group after 30 days of withdrawal, so the sensor was able to identify the alcohol consumption in rats and to monitor the recovery of glycosylation level after 30 days of withdrawal, even combined with cocaine. Furthermore, the effect of sex was also considered. Receiver operating characteristic (ROC) curves were developed for each sex and the corresponding cut-off values were determined. The sensor showed a clinical sensitivity of 70% for male and 75% for female, and a specificity of 67% for both sexes. This preclinical validation demonstrated the possibilities of this sensor for point of care testing of alcoholism, even in cocaine addicts, making it a potential tool for diagnosis and monitoring of alcohol consumption in detox treatments for humans.