Naloxone is a synthetic narcotic that acts as an opioid antagonist countering the effect of opioid overdose. It is also co-formulated with buprenorphine (Suboxone®, Zubsolv®, Bunavail™ buccal film) to prevent misuse and to produce withdrawal symptoms if the combination formulation is altered or naloxone is administered parenterally. A pain medication monitoring laboratory evaluated IMCSzyme®, a genetically modified β-glucuronidase, hydrolysis efficiency for the naloxone assay, which deconjugates the major urinary metabolites of naloxone, nornaloxone (noroxymorphone), and 6β-naloxol. The study reported ~70% hydrolysis efficiency at 65 °C for 60 minutes, with satisfactory precision and reproducibility.
IMCSzyme was a satisfactory choice for naloxone hydrolysis assay. Naloxone glucuronide is the most prevalent metabolite in urine relative to the other metabolites monitored. Application to patient sample analysis was 100% successful in detecting positivity of naloxone in all of the Suboxone patient samples tested.
This information was summarized by IMCS from the technical poster “Development of an LC/MS-MS Naloxone Hydrolysis Assay Using a Recombinant Beta-Glucuronidase for Urinalysis” presented by Ameritox, Ltd. at SOFT 2015