Key wordsfentanyl, opioids, carfentanyl, norfentanyl, synthetic, norcarfentanyl, biological, temp, acetyl, related, matrices, lod, ocfentanyl, valeryl, detection, methylfentanyl, furanyl, butyryl, raptor, duis, naloxone, ratio, area, biphenyl, resetek, min, optimized, urine, connecticut, blood, along, flow, compounds, injection, were, method, phase, blank, began, ion, interface, mrm, limit, compound, curve, finally, mobile, using, potency, ultrafast