Gelled and Foamed Microemulsion-based Systems for Cutaneous Drug Delivery of Diclofenac Sodium

• Author / Creator

  Hajjar, Braa M.

• Abstract Topical formulations of diclofenac have become popular for treating various painful inflammatory conditions. Yet, not all formulations are suitable candidates for dermal delivery as the skin acts as a natural barrier that limits drug penetration. This barrier challenges the efficacy of topically administered medications. This dilemma drove the attention to the development of new topical drug delivery systems that enhance drug penetration without compromising its efficacy. Microemulsions (MEs) have gained interest from the pharmaceutical industry due to their ability to provide enhanced topical penetration of wide-ranging hydrophilic and lipophilic compounds. Accordingly, the first study aimed to develop ME based systems loaded with Diclofenac sodium (DS) and investigated their in vitro release performance in comparison to different marketed formulations. The second study was designed to develop, evaluate and in vitro compare the potential of microemulsion-based foam for improving the topical delivery of DS. In the first study, an ME was prepared using caprylocaproyl polyoxyl-8 glycerides, diethylene glycol monoethyl ether, and propylene glycol monolaurate. An ME-based gel was developed to enhance the viscosity of the ME by using carbopol polymer as a gelling agent. The prepared formulations were subjected to different physiochemical stability testing and in vitro drug release using Franz diffusion cells. The drug-loaded ME and its gelled form were physio-chemically stable and had a cumulative release after 6 hr of 76.67 ± 8.63% for the former and 69.28 ± 7.14 % for the latter. This was statistically significant (p 0.0001) compared to different formulations. However, the high viscosity of the ME-based gel might put it in superiority for topical administration without dripping. In the second study, foam-based MEs were prepared using caprylocaproyl polyoxyl-8 glycerides, polyglyceryl-3 dioleate, caprylic capric triglycerides, and water. The prepared formulations were studied for physiochemical stability, in-vitro drug release, foamability and foam stability. The formulated foamable systems exhibited good stability profile. The cumulative release profile of DS from the foam-based ME was the highest among the tested formulations 75.586 ± 9.074 % after 6 hr. According to the foamability and foam stability assessments, the foam generated from the DS-loaded ME had higher stability profile at room temperature and 32°C in comparison to the drug-free foam. Findings from the current research work suggested that the developed DS-loaded ME- based systems might be potential vehicles for enhancing the topical penetration of DS.

• Subjects / Keywords

  • Skin
  • Topical drug delivery
  • Foam
  • Diclofenac
  • Microemulsion
  • Gel
  • Surfactants

• Graduation date

  Fall 2017

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3Q81563Q

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.