title: Physicochemical studies of binary eutectic of ibuprofen and ketoprofen for enhanced transdermal drug delivery.
abstract: METHODS
  The thermodynamic, eutectic, and crystalline properties of ibuprofen and ketoprofen binary mixtures were investigated using differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD).
  
  
  RESULTS
  The DSC studies showed that melting point (61 degrees C), enthalpy (11.3 kJ/mol), and entropy of fusion (33.7 J/K/mol) of the binary eutectic were significantly lower than those of the individual anti-inflammatory drugs (NSAIDs). Due to the melting-point depression and enhanced skin lipid solubility, the steady-state flux of ibuprofen and ketoprofen from preparations of the binary eutectic increased as compared to pure NSAIDs using shed snakeskin as a model membrane. The NSAID membrane flux values were calculated by flux ratio equations based on drug thermodynamic data, and compared to experimental values obtained from permeation studies.
  
  
  CONCLUSIONS
  The proposed flux ratio equations correctly predicted flux increase.
authors.affiliation: Department of Pharmaceutical Sciences, Arnold & Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, Brooklyn, NY, USA.
authors.forename: Xudong
authors.initials: X
authors.lastname: Yuan
authors.forename: Anthony Cesare
authors.initials: AC
authors.lastname: Capomacchia
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D055598:Chemical Phenomena; D004338:Drug Combinations; D016503:Drug Delivery Systems; D007052:Ibuprofen / Q000008:administration & dosage* / Q000737:chemistry*; D007660:Ketoprofen / Q000008:administration & dosage* / Q000737:chemistry*; D010539:Permeability; D012867:Skin / Q000378:metabolism; D012869:Skin Absorption; D012911:Snakes; D012995:Solubility; D013816:Thermodynamics
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004338:Drug Combinations; D007660:Ketoprofen; D007052:Ibuprofen