HUMAS FARMASI USU — The Faculty of Pharmacy, Universitas Sumatera Utara (USU), held a Doctoral Promotion Examination (Open Defense) for the Doctoral Program in Pharmaceutical Sciences for doctoral candidate Minda Sari Lubis on Wednesday, December 10, 2025, starting at 10:00 a.m. WIB until completion. The open defense was conducted offline at the IMT-GT Room, Academic Management Board (BPA) Building, Universitas Sumatera Utara.
During the examination, the candidate presented her dissertation entitled “The Potential of Salicylic Acid Transethosome Gel with Aloe Vera Gel Concentrate (Aloe vera L.) for Acne Treatment.” This research examines the development of a nanotechnology-based drug delivery system using transethosomes to enhance the effectiveness of acne therapy by increasing the permeation of active substances into the skin.
The doctoral promotion examination was chaired by Prof. Dr. Muryanto Amin, S.Sos., M.Si., Rector of Universitas Sumatera Utara, who served as the presiding chair. Academic supervision was provided by Prof. Dr. Julia Reveny, M.Si., Apt. as Promoter, with Prof. Dr. Poppy Anjelisa Z. Hasibuan, M.Si., Apt. and Prof. Dr. Anayanti Arianto, M.Si., Apt. as Co-Promoters.
The examination also involved External Examiners, namely Prof. Dr. Sumaiyah, M.Si., Apt.; Prof. Yuandani, M.Si., Ph.D., Apt.; Dr. T. Ismanelly Hanum, M.Si., Apt.; and Dr. Endang Sulistyarini Gultom, M.Si., Apt. The examiners provided academic assessments through in-depth discussions, methodological clarification, and scientific dialogue focusing on scientific validity, formulation innovation, and the potential application of the research findings.
In her dissertation, the candidate explained that salicylic acid and aloe vera gel concentrate (AVGC) possess antibacterial activity against acne-causing bacteria, namely Propionibacterium acnes and Staphylococcus epidermidis. The use of transethosomes as nanovesicles aims to enhance the permeation of active substances into the skin layers, thereby improving the effectiveness of topical acne therapy.
AVGC was obtained using the freeze-drying method and analyzed phytochemically, revealing the presence of saponins, flavonoids, glycosides, tannins, and steroids. The effective concentrations were determined to be 0.5% salicylic acid and 12.5% AVGC. The transethosome formulation was optimized using the Simplex Lattice Design method, then characterized and evaluated for antibacterial activity before being formulated into a gel dosage form.
The results showed that the best transethosome formula consisted of 1.5% lecithin, 40% ethanol 96%, 4% Tween 80, and 2% propylene glycol, with a desirability value of 0.868. The resulting transethosomes exhibited small particle size, low polydispersity index, stable zeta potential, spherical vesicle morphology, and stability for up to 12 weeks. The antibacterial inhibition zone of the transethosomes reached approximately 28 mm, while the transethosome gel formulation showed inhibition zones of up to 32 mm.
Further evaluation demonstrated that the transethosome gel possessed acceptable physical characteristics, good stability, no chemical interactions based on FTIR analysis, and rapid release of active substances. The release of salicylic acid and flavonoids exceeded 89% within 480 minutes, with permeation flux decreasing over time. The anti-acne effectiveness test on rat skin showed results nearly equivalent to the reference product Medi-Klin®.
Overall, the study concluded that the salicylic acid–AVGC transethosome gel has good stability, strong antibacterial activity, and promising anti-acne effectiveness, making it a potential innovative topical formulation for acne therapy.
The implementation of this Doctoral Promotion Examination also contributes to the achievement of the Sustainable Development Goals (SDGs), including:
SDG 3 (Good Health and Well-Being): Supporting the development of more effective and safer acne therapies through nanotechnology-based pharmaceutical innovations.
SDG 4 (Quality Education): Realizing high-quality doctoral education through in-depth, innovative, and problem-oriented research in health.
SDG 9 (Industry, Innovation, and Infrastructure): Encouraging the strengthening of pharmaceutical research and innovation, particularly in the development of drug delivery systems and modern topical formulations.
Through the organization of this open defense, the Faculty of Pharmacy, Universitas Sumatera Utara reaffirms its commitment to developing leading research, strengthening academic culture, and producing doctoral graduates who are able to make tangible contributions to science and public health.