ARK Fentanyl II Assay

The ARK™ Fentanyl II Assay is a homogeneous enzyme immunoassay for the qualitative detection of fentanyl in human urine, at a cut-off concentration of 1.0 ng/mL.

Assay Characteristics

  • Highly sensitive and specific detection of fentanyl in human urine
  • Excellent cross-reactivity to norfentanyl (15 ng/mL)
  • No significant unwanted cross-reactivities
  • Cut-off at 1.0 ng/mL
  • Extremely low background noise
  • Liquid stable, ready-to-use reagents, calibrators, and controls
  • Application protocols for most clinical chemistry analyzers


Fentanyl is a synthetic opioid narcotic analgesic similar to morphine; however, it is 50 to 100 times more potent than morphine. Fentanyl is prescribed for patients with chronic pain and used to manage pain after surgery or for the treatment of breakthrough pain in cancer patients. It is available in various forms: by injection (intravenous or intramuscular), transdermal patch, and orally (as a transmucosal lozenge or film).

Fentanyl is highly potent, but shows only a short duration of action. Due to its intense euphoric effects, Fentanyl is frequently misused. Patients receiving fentanyl treatment should be monitored regularly for signs of misuse, abuse, or dependence. Overdoses can lead to respiratory depression and even death.

Although the ARK Fentanyl II Assay detects fentanyl in human urine, it is not designed to distinguish between proper use and substance abuse.