Ozgur Esim

Dr. Ozgur Esim

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 October 2020 in DARU Journal of Pharmaceutical Sciences
Verified
Journal Article
Closed access
PDF file
OEOzgur Esim
Ozgur Esim
NBNurgul K. Bakirhan
Nurgul K. Bakirhan
NYNuray Yildirim
Nuray Yildirim
MSMeral Sarper
Meral Sarper
ASAyhan Savaser
Ayhan Savaser
YOYalcin Ozkan
Yalcin Ozkan

1 April 2020 in Saudi Pharmaceutical Journal
Verified
Journal Article
Open access
OEOzgur Esim
Ozgur Esim
MSMeral Sarper
Meral Sarper
COCansel K. Ozkan
Cansel K. Ozkan
SOSema Oren
Sema Oren
BBBaris Baykal
Baris Baykal
YOYalcin Ozkan
Yalcin Ozkan
Multidrug resistance (MDR) is the most common problem of inadequate therapeutic response in tumor cells. Many trials has been developed to overcome drug efflux by P-glycoprotein (P-gp). For instance, co-administration of a number of drugs called chemosensitizers or MDR modulators with a chemotherapeutic agent to inhibit drug efflux. But for optimal synergy, the drug and inhibitor combination may need to be temporally colocalized in the tumor cells. In this study, we encapsulated the Ver and Dox in PLGA nanoparticles to inhibit the P-gp drug efflux in breast cancer. Moreover, the effect of either Dox solution (DoxS), Dox nanoparticles (DoxNP), DoxS + VerS, DoxNP + VerS, DoxNP + VerNP or Dox-VerNP was evaluated. It was found that co administration of DoxNP with VerNP (70.76%) showed similar cellular uptake of Dox to Dox/Ver combination solution (70.62%). However it is observed that DoxNP + VerNP has the highest apoptotic activity (early apoptotic 13.52 ± 0.06%, late apoptotic 53.94 ± 0.15%) on human breast adenocarcinoma (MCF 7) cells. Hence, it is suggested that DoxNP + VerNP is a promising administration for tumor therapy.

1 March 2021 in Current Pharmaceutical Analysis
Verified
Journal Article
Closed access
PDF file
COCansel Kose Ozkan
Cansel Kose Ozkan
OEOzgur Esim
Ozgur Esim
ASAyhan Savaser
Ayhan Savaser
YOYalcin Ozkan
Yalcin Ozkan
The content and the application of pharmaceutical dosage forms must meet several basic requirements to ensure and maintain efficiency, safety and quality. A large number of active substances have a limited ability to direct administration. Excipients are generally used to overcome the limitation of direct administration of these active substances. However, the function, behavior and composition of the excipients need to be well known in the design, development and production of pharmaceutical dosage forms. In this review, excipients used to assist in any pharmaceutical dosage form production processes of drugs, to preserve, promote or increase stability, bioavailability and patient compliance, to assist in product identification/separation, or to enhance overall safety and effectiveness of the drug delivery system during storage or use are explained. Moreover, the use of these excipients in drug delivery systems is identified. Excipient toxicity, which is an issue discussed in the light of current studies, also discussed in this review.


26 February 2021 in Current Drug Delivery
Verified
Journal Article
Closed access
PDF file
OEOzgur Esim
Ozgur Esim
ASAyhan Savaser
Ayhan Savaser
LKLeyla Karadurmus
Leyla Karadurmus
NBNurgul K. Bakirhan
Nurgul K. Bakirhan
Sibel OzkanSibel Ozkan
Sibel Ozkan
YOYalcin Ozkan
Yalcin Ozkan
Migraine is a chronic, painful, neurological disorder that affects approximately 15% of the population worldwide. It is a form of neurovascular headache: a disorder in which neural events result in the dilation of blood vessels that, in turn, results in pain and further nerve activation. The pathogenesis of migraine was not completely understood but it is thought that both central and peripheral stimulations can play a role in migraine. Experimental pharmacological evidence suggests that some drugs can have actions at migraine treatment and oral drug delivery is the first choice for these drugs. However, the oral absorption of many drugs is delayed during migraine attacks. Therefore, there may be an advantage to other drug delivery routes such as parenteral and intranasal. Moreover, nanoparticles can be used for improved drug delivery of anti-migraine agents as they can protect the encapsulated drug from biological and/or chemical degradation, and extracellular transport by P-gp efflux proteins. Various analytical studies have been performed to sensitive and selective assays of antimigraine drugs from commercial and real samples. The single or combination with other drugs of anti-migraines can be easily detected by several analytical methods such as ultraviolet spectrometry, visible spectrometry, high performance liquid chromatography, liquid chromatography- mass spectrometry, high performance thin layer chromatography. This review focuses on the status of anti-migraine drug delivery technologies and possible routes for drug delivery. Moreover, it will present their analytical assays with different methods.

15 September 2020 in Current Drug Delivery
Verified
Journal Article
Closed access
PDF file
OEOzgur Esim
Ozgur Esim
COCansel K. Ozkan
Cansel K. Ozkan
MSMeral Sarper
Meral Sarper
ASAyhan Savaser
Ayhan Savaser
YOYalcin Ozkan
Yalcin Ozkan
Background: Compared to polymeric nanoparticles prepared using non-lipid surfactants, lecithin addition forms larger nanoparticles and exhibits higher drug loading and the stability of nanoparticles can be conferred by adding Vitamin E Polyethylene Glycol Succinate (TPGS) into the formulation. Aim: The aim of this study is to prepare Gemcitabine (Gem) loaded lecithin/PLGA nanoparticles. Moreover, the effect of TPGS and sodium cholate (SK) on the preparation of lecithin/PLGA nanoparticles was compared. Methods: It was found that while PC addition into PLGATPGS nanoparticles formed larger particles (251.3± 6.0 nm for Gem-PLGATPGS NPs and 516,9 ± 3.9 nm for Gem-PLGA-PCTPGS NPs), the particle size of PLGASK nanoparticles was not affected by lecithin addition (p>0.05). Results: In cytotoxicity studies, it was found that the SK-MES-1 cell inhibition rates of Gem-PLGATPGS NPs, Gem-PLGA-PCTPGS NPs, Gem-PLGASK NPs, Gem-PLGA-PCSK NPs were similar with free Gem (p>0.05). In cytotoxicity studies, it was found that the encapsulation into nanoparticles did not change the cytotoxicity of the drug. However, higher cellular uptake has been observed when the lecithin was used in the preparation of PLGA nanoparticles. Conclusion: Compared with free Gem, the Gem-loaded nanoparticles enhanced the uptake of the drug by SK-MES-1 cells which can increase the effect of gemcitabine for non-small cell lung cancer therapy.