title: Enhanced dissolution of sildenafil citrate as dry foam tablets.
abstract: Dry foam formulation technology is alternative approach to enhance dissolution of the drug. Sildenafil citrate was suspended in sodium dodecyl sulfate solution and adding a mixture of maltodextrin and mannitol as diluent to form a paste. Sildenafil citrate paste was passed through a nozzle spray bottle to obtain smooth foam. The homogeneous foam was dried in a vacuum oven and sieved to obtain dry foam granules. The granules were mixed with croscarmellose sodium, magnesium stearate and compressed into tablet. All formulations were evaluated for their physicochemical properties and dissolution profiles. All the tested excipients were compatible with sildenafil citrate by both differential scanning calorimetry (DSC) and infrared (IR) analysis. There are no X-ray diffraction (XRD) peaks representing crystals of sildenafil citrate observed form dry foam formulations. The hardness of tablets was about 5 kg, friability test <1% with a disintegration time <5 min. The sildenafil citrate dry foam tablet had higher dissolution rate in 0.1 N HCl in comparison with commercial sildenafil citrate tablet, sildenafil citrate prepared by direct compression and wet granulation method. Sildenafil citrate dry foam tablet with the high-level composition of surfactant, water and diluent showed enhanced dissolution rate than that of the lower-level composition of these excipients. This formulation was stable under accelerated conditions for at least 6 months.
authors.affiliation: a Drug and Cosmetic Research and Development Unit , Walailak University , Nakhon Si Thammarat , Thailand.|b School of Pharmacy , Walailak University , Nakhon Si Thammarat , Thailand.
authors.forename: Somchai
authors.initials: S
authors.lastname: Sawatdee
authors.affiliation: a Drug and Cosmetic Research and Development Unit , Walailak University , Nakhon Si Thammarat , Thailand.|b School of Pharmacy , Walailak University , Nakhon Si Thammarat , Thailand.
authors.forename: Apichart
authors.initials: A
authors.lastname: Atipairin
authors.affiliation: a Drug and Cosmetic Research and Development Unit , Walailak University , Nakhon Si Thammarat , Thailand.|b School of Pharmacy , Walailak University , Nakhon Si Thammarat , Thailand.
authors.forename: Attawadee
authors.initials: A
authors.lastname: Sae Yoon
authors.affiliation: c Drug Delivery System Excellence Center and Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences , Prince of Songkla University , Hat Yai, Songkhla , Thailand.
authors.forename: Teerapol
authors.initials: T
authors.lastname: Srichana
authors.affiliation: d Faculty of Pharmacy , Rungsit University , Pathum Thani , Thailand.
authors.forename: Narumon
authors.initials: N
authors.lastname: Changsan
mesh_terms: D002152:Calorimetry, Differential Scanning; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D003460:Crystallization; D065546:Drug Liberation; D005079:Excipients / Q000737:chemistry*; D006244:Hardness; D008353:Mannitol / Q000737:chemistry; D058986:Phosphodiesterase 5 Inhibitors / Q000008:administration & dosage / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D000068677:Sildenafil Citrate / Q000008:administration & dosage* / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D005079:Excipients; D058986:Phosphodiesterase 5 Inhibitors; D011134:Polysaccharides; D013501:Surface-Active Agents; D013607:Tablets; D012967:Sodium Dodecyl Sulfate; D008353:Mannitol; C008315:maltodextrin; D000068677:Sildenafil Citrate; D002266:Carboxymethylcellulose Sodium
keywords: Sildenafil citrate; dissolution; drug release; dry foam tablet