Search

Ibrahim M Abdulbaqi, Yusrida Darwis, Reem Abou Assi, Nurzalina Abdul Karim Khan School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia Introduction: Colchicine is used for the treatment of gout, pseudo-gout, familial Mediterranean fever, and many other illnesses. Its oral administration is associated with poor bioavailability and severe gastrointestinal side effects. The drug is also known to have a low therapeutic index. Thus to overcome these drawbacks, the transdermal delivery of colchicine was investigated using transethosomal gels as potential carriers.Methods: Colchicine-loaded transethosomes (TEs) were prepared by the cold method and statistically optimized using three sets of 24 factorial design experiments. The optimized formulations were incorporated into Carbopol 940® gel base. The prepared colchicine-loaded transethosomal gels were further characterized for vesicular size, dispersity, zeta potential, drug content, pH, viscosity, yield, rheological behavior, and ex vivo skin permeation through Sprague Dawley rats’ back skin.Results: The results showed that the colchicine-loaded TEs had aspherical irregular shape, nanometric size range, and high entrapment efficiency. All the formulated gels exhibited non-Newtonian plastic flow without thixotropy. Colchicine-loaded transethosomal gels were able to significantly enhance the skin permeation parameters of the drug in comparison to the non-ethosomal gel.Conclusion: These findings suggested that the transethosomal gels are promising carriers for the transdermal delivery of colchicine, providing an alternative route for drug administration. Keywords: transethosomes, ethosomal nanocarriers, colchicine, factorial design, skin permeation, rheology

Ibrahim M Abdulbaqi, Yusrida Darwis, Nurzalina Abdul Karim Khan, Reem Abou Assi, Arshad A Khan School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia Abstract: Ethosomal systems are novel lipid vesicular carriers containing a relatively high percentage of ethanol. These nanocarriers are especially designed for the efficient delivery of therapeutic agents with different physicochemical properties into deep skin layers and across the skin. Ethosomes have undergone extensive research since they were invented in 1996; new compounds were added to their initial formula, which led to the production of new types of ethosomal systems. Different preparation techniques are used in the preparation of these novel carriers. For ease of application and stability, ethosomal dispersions are incorporated into gels, patches, and creams. Highly diverse in vivo models are used to evaluate their efficacy in dermal/ transdermal delivery, in addition to clinical trials. This article provides a detailed review of the ethosomal systems and categorizes them on the basis of their constituents to classical ethosomes, binary ethosomes, and transethosomes. The differences among these systems are discussed from several perspectives, including the formulation, size, ζ-potential (zeta potential), entrapment efficiency, skin-permeation properties, and stability. This paper gives a detailed review on the effects of ethosomal system constituents, preparation methods, and their significant roles in determining the final properties of these nanocarriers. Furthermore, the novel pharmaceutical dosage forms of ethosomal gels, patches, and creams are highlighted. The article also provides detailed information regarding the in vivo studies and clinical trials conducted for the evaluation of these vesicular systems. Keywords: ethosomes, transdermal, lipid-based vesicles, delivery systems

In-situ polymerization technique was used to prepare epoxy/organo-montmorillonite (OMMT) nanocomposites by three different mixing sequence methods. The mechanical and morphological properties of epoxy/ OMMT nanocompositeE were studied by flexural tests, fracture toughness (SENB), Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). The flexural modulus of epoxy was improved significantly by the incorporation of OMMT. This is attributed to the reinforcement and exfoliation/intercalation of the OMMT. The XRD results showed the formation of exfoliated structure in the epoxy/OMMT nanocomposites. Sequence of mixing influenced the dispersion and intercalation/exfoliation of the OMMT in the epoxy matrix. Appropriate mixing sequence should be selected in order to achieve better exfoliation of OMMT and higher flexural modulus and strength of the epoxy nanaocomposites. In this study, computer aided statistical methods of experimental design (Response Surface Methodology, RSM) was used to investigate the process variables on the flexural properties of epoxy/OMMT nanocomposites. Speed of mechanical stirrer, post-curing time and post-curing temperature were chosen as process variables in the design experimental. Results showed that the speed of mechanical stirrer post-curing time and post-curing temperature were able to influence the flexural modulus and flexural yield stress of epoxy/OMMT nanocomposites.