Ege Üniversitesi İlaç Araştırma Geliştirme ve Farmakokinetik Uygulama Merkezi’nin (ARGEFAR) ilk Üniversite Sanayi İşbirliği Projesini yönetti. Bal Arılarında kullanılmak üzere Varroaya karşı Uçucu yağlardan oluşan jel geliştirdi. Mertsel fabrikasının ürünlerini geliştirdi. Fabrikanın üretim hattını kurdu. Tübitak Projesi kapsamında Türkiye’nin ilk antibakteriyel bariyer kremini geliştirdi ve ruhsatını aldı. Sıcaklık dönüşümlü yanık jeli geliştirerek patent aldı. 2014 senesinde ELAA PHARM A.Ş. kurdu. markasını yaratarak İzmir’de franchise modeline uygun Bitkisel Kozmetik konseptini hayata geçirdi. Satış ekiplerinde medikal eğitimler verdi. 2018 yılında Naturin Nutraceuticals fabrika müdürü oldu. İstanbul’da yeni kurulan Nova Nutrica firmasına mentorluk yaptı. ELAA PHARM A.Ş. Yön. Kur. Başkanı ve Kurucusudur. Kozmetik Üreticileri ve Araştırmacıları Derneği’nde Yönetim Kurulu Üyeliği ve Başkan yardımcılığı görevlerini yürüttü. DALE PHARMA A.Ş. Kurucu Yönetim Kurulu Üyesidir.
EDUCATION
Lisans Eczacılık Fakültesi Ege Üniversitesi
Y. Lisans Farmasötik Teknoloji Anabilim Dalı Ege Üniversitesi – Sağlık Bilimleri Enstitüsü
Doktora Farmasötik Teknoloji Anabilim Dalı Ege Üniversitesi – Sağlık Bilimleri Enstitüsü
RESEARCH INTERESTS
Eczacılık, Ürün geliştirme, Üretim, Bitkisel ilaçlar, Kozmetik, Mikroemülsiyon, Sol-jel
13
Scopus Publications
Scopus Publications
Thermoresponsive Sol–Gel System Incorporating Oleuropein-Rich Olive Leaf Extract for Enhanced Wound Healing and Antibiofilm Activity Levent Alparslan, Samet Özdemir, Burak Karacan, Gülşah Torkay, Ayca Bal-Öztürk, et al. Gels, 2026 Oleuropein, the principal secoiridoid phenolic compound of olive leaves (Olea europaea L.), is recognized for its broad-spectrum antimicrobial, antibiofilm, antioxidant, and tissue-regenerative properties. However, its effective local therapeutic application remains challenging due to rapid clearance from the site of administration and limited residence time. In this study, an oleuropein-rich aqueous olive leaf extract was incorporated into a thermoresponsive sol–gel delivery system designed for localized application. The formulation was engineered to remain in a low-viscosity sol state at room temperature and to undergo a temperature-triggered sol-to-gel transition near physiological temperature (~33 °C), enabling in situ gel formation. Oleuropein content was quantified using a validated HPLC method, and the formulation was characterized with respect to physicochemical parameters, thermoreversible gelation behavior, particle size distribution, mechanical properties, and spreadability. Biological performance was evaluated through in vitro cytocompatibility (MTT assay), fibroblast migration (scratch assay), and collagen deposition (Sirius Red staining) in L929 fibroblasts, as well as antibiofilm activity against representative Gram-positive and Gram-negative bacterial strains. The developed sol–gel system demonstrated stable physicochemical characteristics, rapid and reversible thermogelation, suitable mechanical and spreading properties, concentration-dependent inhibition of biofilm formation, and acceptable cytocompatibility within the tested concentration range. Notably, the formulation supported fibroblast viability and collagen-associated responses at optimized concentrations. Overall, the results indicate that the proposed thermoresponsive sol–gel formulation represents a promising strategy for the localized delivery of oleuropein-rich olive leaf extract, combining physicochemical stability with dual wound-healing and antibiofilm functionality.
Formulation and Characterization of an Oleuropein-Enriched Oral Spray Gel: Microbiological Performance and In Ovo Histopathological Safety Levent Alparslan, Samet Özdemir, Burak Karacan, Ömer Faruk Tutar, Tunay Doğan, et al. Pharmaceutics, 2026 Background/Objectives: Oleuropein is a bioactive phenolic compound from olive leaves with antimicrobial and antioxidant activity. This study aimed to develop a sprayable oral gel containing an oleuropein-rich aqueous extract and to evaluate its pharmaceutical performance antimicrobial efficacy and in ovo biological response. Methods: Oleuropein content was quantified using a validated chromatographic method. Polymeric systems were screened to select an optimized sprayable formulation. Physicochemical stability, dose uniformity, and antimicrobial activity against major cariogenic bacteria were evaluated. In ovo biological evaluation was conducted using the chick chorioallantoic membrane angiogenesis model together with histopathological examination of embryonic heart and liver tissues. Results: Oleuropein content was determined as 288.6 µg/mL in the olive leaf extract and 255.1 µg/mL in the final formulation. The optimized oral spray showed stable physicochemical properties, with pH maintained at 6.90 ± 0.02 and no relevant changes in viscosity during storage. The mean delivered dose per actuation was 0.128 ± 0.015 g, corresponding to 32.6 µg oleuropein per spray. The formulation exhibited inhibitory activity against all tested cariogenic microorganisms, with MIC values ranging from 13.3 to 170.7 µg/mL and MBC values generally two-fold higher. In the CAM assay, significant concentration- and time-dependent antiangiogenic effects were observed after 24–48 h at moderate and higher concentrations. Histopathological evaluation revealed dose-dependent acute degenerative and congestive changes in heart and liver tissues without evidence of fibrosis or steatosis. Conclusions: The oleuropein-based sprayable oral gel is a promising localized delivery system with adequate stability dose uniformity and antimicrobial efficacy. In ovo findings provide a conservative assessment of systemic exposure and support further development for oral biofilm and caries-related applications.
Smart Thermoresponsive Sol–Gel Formulation of Polyhexanide for Rapid and Painless Burn and Wound Management Levent Alparslan, Gülşah Torkay, Ayca Bal-Öztürk, Çinel Köksal Karayıldırım, Samet Özdemir Polymers, 2025 Traditional wound and burn treatments often fall short in balancing antimicrobial efficacy, patient comfort, and ease of application. This study introduces a novel, transparent, thermoresponsive sol–gel formulation incorporating polyhexamethylene biguanide (PHMB) for advanced topical therapy. Utilizing Poloxamer 407 as a biocompatible carrier, the formulation remains a sprayable liquid at room temperature and instantly gels upon contact with body temperature, enabling painless, pressure-free application on sensitive, injured skin. Comprehensive in vitro and in vivo evaluations confirmed the formulation’s broad-spectrum antimicrobial efficacy (≥5 log10 reduction in 30 s), high biocompatibility (viability > 70% in fibroblasts), non-irritancy (OECD 425-compliant), and physical stability across three months. Importantly, the formulation maintained fibroblast migration capacity—crucial for wound regeneration—while exhibiting rapid sol-to-gel transition at ~34 °C. These findings highlight the system’s potential as a next-generation wound dressing with enhanced user compliance, transparent monitoring capability, and rapid healing support, particularly in disaster or emergency scenarios.
De novo Drug Design to Suppress Coronavirus RNA-Glycoprotein via PNA-Calcitonin Soykan Agar, Barbaros Akkurt, Levent Alparslan Journal of the Turkish Chemical Society Section A Chemistry, 2024 De novo drug design has been studied utilizing the organic chemical structures of Salmon Calcitonin 9 - 19 and Peptide Nucleic Acid (PNA) to suppress Coronavirus Ribonucleic Acid (RNA)-Glycoprotein complex. PNA has a polyamide backbone and Thymine pendant groups to selectively bind and inhibit Adenine domains of the RNA-Glycoprotein complex. While doing so, molecular docking and molecular dynamics studies revealed that there is great inhibition docking energy (-12.1 kcal/mol) with significantly good inhibition constant (124.1 µM) values confirming the efficient nucleotide-specific silencing of Coronavirus RNA-Glycoprotein complex.
Analysis of Surgical Masks Adverse Effects on Facial Skin in Long Term Usage During COVID-19 Pandemic Abdullah Levent ALPARSLAN, Kıvanç YÜKSEL, Khaetthareeya SUTTHANUT Turkish Journal of Pharmaceutical Sciences, 2024 Objectives: During the coronavirus disease-2019 pandemic, masks have become mandatory for protection against the virus transmitted by breathing. This study examined the impact of surgical masks used daily on civilian facial skin. Materials and Methods: Moisture, elasticity, pore, melanin, acne, wrinkle, and sensitivity parameters of 83 volunteers were measured numerically using an API-100 skin analyzer and camera recordings. Numerical values were compared following the device’s algorithm calibrated according to age, gender, and race. Finally, the obtained data were statistically evaluated and compared with the averages. Results: Pore, melanin, acne, and wrinkle parameters were higher without gender discrimination, whereas moisture and elasticity parameters were low. While a significant increase was observed in women for sensitivity, the increase was not statistically significant in men. Conclusion: The negative effects of long-term daily wearing of surgical masks on facial skin were statistically significant. Therefore, taking outdoor breaks during mask use, washing the face intermittently, using moisturizing and purifying cosmetic products, and anti-wrinkle effects have been proposed to reduce the possible defects.
A Comprehensive Study on Peppermint Oil and Cinnamon Oil as Nanoemulsion: Preparation, Stability, Cytotoxicity, Antimicrobial, Antifungal, and Antioxidant Activity Emrah Özakar, Levent Alparslan, M. Cemal Adıgüzel, Gülşah Torkay, Alper Baran, et al. Current Drug Delivery, 2024 Background: Recent studies have shown that nanoemulsions prepared with essential oils have significant antimicrobial potential against multidrug-resistant pathogens due to increased chemical stability. Nanoemulsion also promotes controlled and sustained release, which increases their bioavailability and efficacy against multidrug-resistant bacteria. Objective: This study aimed to investigate the antimicrobial, antifungal, antioxidant, and cytotoxicity properties of cinnamon essential oil and peppermint essential oil as nanoemulsions compared to pure forms. For this purpose, analyses of the selected stable nanoemulsions were carried out. Method: The droplet sizes and zeta potentials of peppermint essential oil nanoemulsions and cinnamon essential oil nanoemulsions were found to be 154.6±1.42 nm and -17.1±0.68 mV and 200.3±4.71 nm and -20.0±0.81 mV, respectively. Although the amount of essential oil used in nanoemulsions was 25% w/w, antioxidant and antimicrobial activities were found to be more effective compared to pure essential oils. Results: In cytotoxicity studies on the 3T3 cell line, both essential oil nanoemulsions showed higher cell viability than pure essential oils. At the same time, cinnamon essential oil nanoemulsions exhibited a higher antioxidant property than peppermint essential oil nanoemulsions and showed superiority in the antimicrobial susceptibility test conducted against four bacteria and two fungi. Cell viability tests determined that cinnamon essential oil nanoemulsions showed considerably higher cell viability compared to pure cinnamon essential oil. Conclusion: These findings indicated that the prepared nanoemulsions in the current study might positively influence the dosing regimen and clinical outcomes of antibiotic therapy.
Thermoreversible Gel Formulation for the Intranasal Delivery of Salmon Calcitonin and Comparison Studies of In Vivo Bioavailability Abdullah Levent ALPARSLAN, Gülbeyaz YILDIZ TÜRKYILMAZ, Leyla Didem KOZACI, Ercüment KARASULU Turkish Journal of Pharmaceutical Sciences, 2023 Objectives We developed original thermoreversible (sol-gel) formulations of salmon calcitonin (sCT) for nasal applications. The sol-gel has been compared with commercial intranasal sprays in vitro and in vivo studies. The aim of studying sol-gel form is to arrange the viscosity of formulations for a reversible adequate fluidity at different temperatures. This situation may facilitate the use of drugs as sprays and increase the bioadhesive ability to mucosa. Materials and Methods Characterization of optimum formulations was studied. Validated analytical assays determined the number of sCT. An approximately equal number of commercial and sol-gel dosages were sprayed into the nostrils of the rabbits. Blood samples were collected from the ear veins of rabbits and determined by enzyme immunoassay plates. These plates were evaluated by Thermo Labsystem Multiscan Spectrum at 450 nm. Thanks to Winnonlin 5.2, pharmacokinetic data were evaluated by a non-compartmental method. Results The absolute bioavailability of the formulation at pH 4 and the commercial product (CP) was compared by evaluating the primary pharmacokinetic data area under the curve 0→tlast. The absolute bioavailability of the commercial intranasal spray was measured 1.88 based on maximum concentration (Cmax) assessment. Cmax of the sol-gel formulation pH 4 was calculated as 0.99 and the relative bioavailability was obtained 53.3%. Conclusion In vivo pharmacokinetic data of sol-gel formulation with pH 3 showed significantly higher volume of distribution parameter than the CP (111167>35408). It is thought that the formulation adhered to the nasal mucosa releases sCT slowly and less.
O/W microemulsion and hydrogel formulation of methotrexate and comparison of releasing studies. Abdullah Levent ALPARSLAN, Ercument KARASULU, Gulbeyaz Yildiz TÜRKYILMAZ, Dogan UVEY Journal of Research in Pharmacy, 2023 : Microemulsions are ideal carriers for poorly soluble substances. They increase the absorption of drugs with low bioavailability. Methotrexate (MTX), which is used internally in cancer and psoriasis and has many side effects and it is less soluble in water and its passage through the skin is problematic due to its high molecular weight. An O/W microemulsion formulation containing MTX has been developed in order to reduce the side effects of the drug, not to have a first pass effect on the liver, to increase its bioavailability in topical use and to provide ease of use to patients. The releasing profiles of the gel formulation, prepared by reducing the fluidity of these formulations by polymers, were investigated through the nylon membrane. Mostly W/O microemulsion systems are available due to design of preparations but in this study O/W microemulsions and gel forms containing MTX were designed for topical use. Innovation side of trials will inspire in vivo studies and clinical studies that may cause less harm to patients dermatologically and provide optimal effect.
Sodium hyaluronate dry powder inhalation in combination with sodium cromoglycate prepared using optimized spray drying conditions Gülbeyaz Yildiz Türkyilmaz, Kemal Volkan Özdokur, Levent Alparslan, Ercüment Karasulu Pharmaceutical Development and Technology, 2023 Sodium hyaluronate (SHA) is an anti-inflammatory and protective agent against bronchoconstriction, and sodium cromoglicate (SCG) prevents exercise-induced bronchoconstriction and inflammation. Based on the pharmacological properties of both substances, this study aimed to develop a dry powder inhaler (DPI) of SHA alone and in combination with SCG. The target of the study was to develop flowable formulations without any surfactants by using the spray drying method. To obtain respirable SHA and SCG:SHA particles, variables of the spray dryer, such as inlet temperature, atomized air flow, and feed solution, were changed. The particles 1-8 μm in size were produced with high yield by spray drying and increasing the ethanol percentage of the feed solution (60%), which is the most remarkable parameter. After that, physicochemical characterizations were performed. The aerosol performance of DPI formulations prepared using lactose was evaluated using Handihaler® DPI. The fine particle fraction (FPF) was 36% for the SHA formulation, whereas it was 52 and 53% for SCG and SHA, respectively, in the SCG:SHA formulation. Consequently, both particles were produced reproducibly by spray drying, and inhaled SHA and SCG:SHA dry powder formulations were developed due to their high FPF and flowability with lactose.
