BACKGROUND

Opiates/opioids and benzodiazepines are commonly prescribed drug therapies for acute and chronic pain. Urine drug testing is often employed to assess adherence to these mediations. Opioids and benzodiazepines are drug classes that undergo extensive metabolism through glucuronidation/sulfation. Conjugated glucuronide and sulfate drug metabolites can be difficult to detect by immunoassay and mass spectrometry methods. Consequently, false-negative or false-positive results can have a damaging impact on patient care. A common dilemma among drug-testing laboratories is whether to perform preanalytical hydrolysis to increase detection of drugs that are highly conjugated as metabolites.

METHODS

The purpose of hydrolysis is to cleave the glucuronide or sulfate compounds to enhance analyte detection by increasing the parent drug concentration of those drugs that are primarily metabolized by glucuronidation or sulfation. Hydrolysis procedures can be performed by acid, base, or enzyme sources (β-glucuronidase).

RESULTS

Preanalytical hydrolysis can improve the overall detection of most opioids and benzodiazepine drugs. However, the limitation of this procedure is that the process can be time-consuming and prolong the turnaround time to result. In addition, chemical hydrolysis has the potential to degrade opioid and benzodiazepine drugs, whereas incomplete hydrolysis and variable hydrolysis efficiencies can occur with an enzymatic approach.

CONCLUSIONS

Preanalytical hydrolysis can improve the sensitivity of drug detection for drug classes such as opiates/opioids and benzodiazepines, which are highly metabolized by glucuronidation and sulfation and should be implemented in analytical procedures to convert conjugated metabolites into the free (unbound) form.