Comparative spermicidal performance of iodinated and non-iodinated contraceptive formulations of nonoxynol-9 co-precipitated with polyvinylpyrrolidone.
The objective of this study was to evaluate the spermicidal qualities of various combinations of nonoxynol-9 (N-9; whole molecule = oligomers 1-18) and its isolated fractions (oligomers 8-10, 4-6 and 1-3), co-precipitated with non-iodinated and/or iodinated (Io) polyvinylpyrrolidone (PVP) as possible vaginal contraceptives. Spermicidal qualities of known equimolar concentrations of various combinations of PVP/N-9 and PVP-Io/N-9 were tested via a modified Sander-Cramer test (SCT) using human spermatozoa. Spermicidal agents and semen samples were mixed 1:1 (v/v) and evaluated for sperm viability. Spermicidal activity was reported as the minimal concentration (microgram/mL) of spermicide capable of killing all spermatozoa within 20 sec after exposure to the spermicide. The spermicidal activity of PVP/N-9 and PVP-Io/N-9 preparations containing N-9 oligomers 1-18 and/or 8-10 was similar, and these preparations were more efficient in killing the spermatozoa than the ones containing N-9 oligomers 4-6 and 1-3. Polyvinyl-pyrrolidone proved to be an effective vehicle for PVP/N-9 and PVP-Io/N-9 preparations, especially those containing N-9 oligomers 4-6 and 1-3. Incorporation of Io into the spermicidal preparations brought about additional efficacy. The current findings could be of clinical significance in future studies when preparing and delivering those selected co-precipitates vaginally.
Zavos
P M
PM
Department of Animal Sciences, College of Agriculture, University of Kentucky, Lexington 40546, USA.
Correa
J R
JR
Nosek
D
D
Mohammadi
F
F
Digenis
G A
GA
D002470:Cell Survival / Q000187:drug effects; D011232:Chemical Precipitation; D005260:Female; D006801:Humans; D007455:Iodine; D008297:Male; D017137:Nonoxynol / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology*; D011205:Povidone / Q000737:chemistry*; D013089:Spermatocidal Agents / Q000008:administration & dosage / Q000494:pharmacology*; D013094:Spermatozoa / Q000187:drug effects
D013089:Spermatocidal Agents; D017137:Nonoxynol; D007455:Iodine; D011205:Povidone