Nonionic surfactant structure on the drug release, formulation and physical properties of ethylcellulose microspheres.

Evaluate the effects of nonionic surfactants Brij 58 and Tween 40 with different structures but similar hydrophilic lipophilic balances (HLBs) on theophylline (TH)-loaded ethylcellulose (EC) microspheres. Microspheres were formulated using ratios of the surfactants with matching HLB values but different chemical-structures at temperatures (22/35 °C) by hydrophobic solvent-emulsion evaporation. Particle size, GMD, drug loading, encapsulation efficiency and dissolution were evaluated.

Influence of physicochemical properties on the in vitro skin permeation of the enantiomers, racemate, and eutectics of ibuprofen for enhanced transdermal drug delivery.

Physicochemical properties of chiral ibuprofen are significant to formulation scientists because its enantiomers and eutectics possess lower melting points than its racemate. The influence of these properties on transdermal formulation development, especially the relative effect of lowered melting point, on skin permeation must be carefully assessed to provide the most efficacious formulation. Thermodynamic properties and crystalline structures of the enantiomers, eutectics, and racemate of chiral ibuprofen were investigated by differential scanning calorimetry and X-ray powder diffraction.

Formulation parameters and release mechanism of theophylline loaded ethyl cellulose microspheres: effect of different dual surfactant ratios.

Altering the combined hydrophilic-lipophilic balance (CHLB), by varying the ratio of dual surfactants, on formulation parameters and in vitro drug release of ethyl cellulose microspheres was examined. Theophylline, a xanthine bronchodilator was used to model controlled release owing to its narrow therapeutic index. Microspheres were prepared using different ratios of dual surfactant in an emulsion-solvent evaporation process.

Transdermal permeation of novel n-acetyl-glucosamine/NSAIDs mutual prodrugs.

The current investigation reports skin permeation of three novel mutual prodrugs (MP) which couple n-acetyl-glucosamine with an NSAID, either ketoprofen or ibuprofen. They were evaluated for transdermal permeation using shed snakeskin, and to our knowledge represent the first MPs synthesized for this purpose, although they also could be used for subcutaneous delivery. MPs are defined as two active drug compounds usually connected by an ester linkage.

Physicochemical studies of binary eutectic of ibuprofen and ketoprofen for enhanced transdermal drug delivery.

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.

Transdermal permeability of N-acetyl-D-glucosamine.

Transdermal permeation of N-acetyl-D-glucosamine (NAG), a metabolite of glucosamine was examined. Glucosamine salts are nutraceuticals used in the oral treatment of osteoarthritis. Sparse information is available regarding glucosamine and NAG transdermal or percutaneous transport and absorption.