Abstract
Sildenafil, the active ingredient in Viagra™, ahs been purified from commercially available tablets. The purification, using Sephadex G25 chromatography under conditions of low ionic strength, is simple and inexpensive. Sildenafil purified according to this protocol has been characterized with respect to its IC50 for PDE5, its ultraviolet absorption profile, and by collision-induced dissociation fingerprinting, positive ion nanospray, and MALDI mass spectrometry. Tritated sildenafil (6 Ci/mmol) was prepared commercially using the sildenafil purified by this protocol and was verified to retain the potency of unlabeled sildenafil. This protocol and similar procedures will allow investigators to easily isolate sufficient amounts of sildenafil or other PDE5 inhibitors for conducting biochemical and in vitro studies of drug action.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 8 print issues and online access
$259.00 per year
only $32.38 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Corbin JD, Francis SH . Cyclic GMP phosphodiesterase-5: target of sildenafil. J Biol Chem 1999; 274: 13729–13732.
Boolell M et al. Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction. Int J Impot Res 1996; 8: 47–52.
Jeremy JY et al. Effects of sildenafil, a type-5 cGMP phosphodiesterase inhibitor, and papaverine on cyclic GMP and cyclic AMP levels in the rabbit corpus cavernosum in vitro. Br J Urol 1997; 79: 958–963.
Michelakis E et al. Oral sildenafil is an effective and specific pulmonary vasodilator in patients with pulmonary arterial hypertension: comparison with inhaled nitric oxide. Circulation 2002; 105: 2398–23403.
Butrous G, Siegel RL . Sildenafil (Viagra) prolongs cardiac repolarization by blocking the rapid component of the delayed rectifier potassium current. Circulation 2001; 103: E119–E120.
Sundkvist E, Jaeger R, Sager G . Pharmacological characterization of the ATP-dependent low Km guanosine 3′,5′-cyclic monophosphate (cGMP) transporter in human erythrocytes. Biochem Pharmacol 2002; 63: 945–949.
Corbin JD, Turko IV, Beasley A, Francis SH . Phosphorylation of phosphodiesterase-5 by cyclic nucleotide-dependent protein kinase alters its catalytic and allosteric cGMP-binding activities. Eur J Biochem 2000; 267: 2760–2767.
Ballard SA et al. Effects of sildenafil on the relaxation of human corpus cavernosum tissue in vitro and on the activities of cyclic nucleotide phosphodiesterase isozymes. J Urol 1998; 159: 2164–2171.
Saenz de Tejada I et al. The phosphodiesterase inhibitory selectivity and the in vitro and in vivo potency of the new PDE5 inhibitor vardenafil. Int J Impot Res 2002; 13: 282–290.
Martins TJ, Mumby MC, Beavo JA . Purification and characterization of a cyclic GMP-stimulated cyclic nucleotide phosphodiesterase from bovine tissues. J Biol Chem 1982; 257: 1973–1979.
Gopal VK, Francis SH, Corbin JD . Allosteric sites of phosphodiesterase-5 (PDE5): a potential role in negative feedback regulation of cGMP signaling in corpus cavernosum. Eur J Biochem 2001; 268: 3304–3312.
Acknowledgements
We thank Lisa Manier and the Vanderbilt University Mass Spectrometry Research Center, the E Bronson Ingram Cancer Center, and the Diabetes Center of Vanderbilt University School of Medicine. We also thank Pfizer for providing purified sildenafil to be used as a standard. This work was supported by NIH DK58277 and DK40029.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Francis, S., Raja Sekhar, K., Rouse, A. et al. Single step isolation of sildenafil from commercially available Viagra™ tablets. Int J Impot Res 15, 369–372 (2003). https://doi.org/10.1038/sj.ijir.3901040
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/sj.ijir.3901040
Keywords
This article is cited by
-
Sildenafil (Viagra) ameliorates clinical symptoms and neuropathology in a mouse model of multiple sclerosis
Acta Neuropathologica (2011)
-
Tyrosine-612 in PDE5 contributes to higher affinity for vardenafil over sildenafil
International Journal of Impotence Research (2006)
-
High biochemical selectivity of tadalafil, sildenafil and vardenafil for human phosphodiesterase 5A1 (PDE5) over PDE11A4 suggests the absence of PDE11A4 cross-reaction in patients
International Journal of Impotence Research (2005)