Quantitative analysis of nonoxynol-9 in blood

At present, there is little data on the level of nonoxynol-9 (N-9) in blood. Using routine methods, the rate of recovery for N-9 in blood has been confirmed to be very low. A method determining N-9 levels in urine has been found but obviously a more efficient method for determining N-9 levels in blood and urine is still needed. Here, a method of determining N-9, a nonionic surfactant spermicide, in blood is presented. The analytical procedure is a simple and convenient method. Using HPLC, UV detector, ODS reversed-phase column, methanol-water mobile phase, NaCl salting-out and two extractions with benzene, a rate of recovery for N-9 of 93 +/- 4% has been obtained.