Bioengineering / Biyomühendislik

Permanent URI for this collectionhttps://hdl.handle.net/11147/4529

Browse

Filters

2018 - 201912020 - 20224

Settings

Institution Author: search.filters.institutionAuthor.Sözmen, Alper Baran

Search Results

Now showing 1 - 5 of 5
  • Article
    Citation - Scopus: 6
    Sensitive and Rapid Protein Assay Via Magnetic Levitation
    (Elsevier, 2022) Sözmen, Alper Baran; Arslan Yıldız, Ahu
    Magnetic levitation (MagLev) is a newly emerging methodology for biosensing that provides a density-based analysis, which is highly sensitive and versatile. In this study, a magnetic levitation based sensor platform was used for protein detection; and sensor platform optimization was performed for both sensitivity and resolution. Bovine Serum Albumin (BSA) was used as a model protein and detection of BSA was carried out by antibody functionalized polystyrene microspheres (PSMs). Various sizes of PSMs were examined and their performances were compared by statistical analyses in terms of limit of detection (LOD), sensitivity, and resolution. Quantification of the protein was done based on the magnetic levitation height differences of antibody functionalized PSMs. For optimization of the methodology, varied PSMs were utilized, and standardization of PSM diameter, concentration of the antibody to be functionalized, and PSM dilution rates were carried out. In conclusion, 20 μm PSMs diluted to 0.005% W/V and functionalized with anti-BSA antibody at a concentration of 28 μg/ml were determined to provide the best resolution for BSA detection. A dynamic range of 100 nM to 1 mM was observed with an LOD value of 4.1 ng/ml. This sensing platform promises a novel approach with a diverse application field and it provides rapid, consistent, and reproducible results with high resolution and sensitivity.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 9
    Optimization of the Algal Species Chlorella Miniata Growth: Mathematical Modelling and Evaluation of Temperature and Light Intensity Effects
    (Elsevier, 2022) Sözmen, Alper Baran; Ata, Ayça; Övez, Bikem
    Growth of Chlorella miniata, a green microalga was investigated during this study under various temperature and light intensity values with the purpose of determining growth rate changes of the microalgae with cultivation parameters, experiments were carried out using airlift photobioreactors with a study volume of 6 L. Culturing conditions were between 66 and 385 μmol photon m−2 s−1 and between 14 and 30 °C for light intensity and ambient temperature, respectively. Acquired data were then used to test various mathematical models for coherency with experimental results. Aiba Model for light intensity and Skewed Normal Distribution Model for temperature parameters performed superior compared to the rest of the mathematical models used during the study. Utilizing both mathematical models a novel model was deduced to express effects of both light intensity and temperature parameters in combination on algal growth. Then the developed model was used to calculate the optimum growth condition of the species. The proposed mathematical model showed good coherency with experimental data and an average relative error of 1.97% for both temperature and light intensity effects on algal growth. The theoretical optimum temperature and light intensity for the maximum specific growth rate were calculated to be 22.43 °C and 291.5 μmol photon m−2 s−1 respectively.
  • Conference Object
    Immobilized Gold Nanoparticle Based Plasmonic Assay Platform for Biomolecule and Microorganism Detection
    (Wiley, 2021) Sözmen, Alper Baran; Arslan Yıldız, Ahu
    Plasmonic sensors are suitable tools for study of molecular interactions. Localized Surface Plasmon Resonance (LSPR) based sensors detect spectral changes associated with intramolecular interactions between analyte molecules and recognition elements. Due to its label­free and highly sensitive features, LSPR based methods have high potential for biosensing applications. In this study, we aim to develop a sensitive, label­free, rapid and simple biosensing platform. For this purpose, a novel refractive index (RI) sensitivity enhancement methodology is proposed by immobilizing gold nanoparticles (GNPs) for platform­based LSPR. Fabrication of platform was carried out by GNP synthesis, immobilization of GNPs on polystyrene solid support, and growth of GNPs. Validation of response to RI changes of developed sensor platform was carried out by tests with varying concentrations of sucrose and ethanol. Then as a proof­of­concept, detection ability and detection limit determination of E.coli BL21 (DE3) and protein Bovine Serum Albumin (BSA) was carried out. Adsorption of E.coli BL21 (DE3) via bulk interactions showed that the developed LSPR platform exhibit high enough binding affinity for bacteria detection, and was able to detect down to concentrations as low as 102 CFU/ml. Immune capturing of BSA via anti­BSA antibody showed that the developed LSPR platform was able to detect BSA protein–antibody interaction down to 10 µM concentration range.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 11
    Cost-Effective and Rapid Prototyping of Pmma Microfluidic Device Via Polymer-Assisted Bonding
    (Springer, 2021) Sözmen, Alper Baran; Arslan Yıldız, Ahu
    Microfluidic systems are relatively new technology field with a constant need of novel and practical manufacturing materials and methods. One of the main shortcomings of current methods is the inability to provide rapid bonding, with high bonding strength, and sound microchannel integrity. Herein we propose a novel method of assembly that overcomes the mentioned limitations. Polymer-assisted bonding is a novel, rapid, simple, and inexpensive method where a polymer is solubilized in a solvent and the constituted solution is used as a bonding agent. In this study, we combined this method with utilization of several phase-changing materials (PCMs) as channel-protective agents. Glauber's salt appeared to be more suitable as a channel-protective agent compared to rest of the salts that have been used in this study. Based on the bonding strength, quality analyses, leakage tests, and SEM imaging, the superior assisting bonding solvent was determined to be dichloromethane with a PMMA concentration of 2.5% (W/V). It showed a bonding strength of 23.794 MPa and a nearly non-visible bonding layer formation of 2.83 mu m in width which is proved by SEM imaging. The said combination of PCM, solvent, and polymer concentration also showed success in leakage tests and an application of micro-droplet generator fabrication. The application was carried out to test the applicability of developed prototyping methodology, which resulted in conclusive outcomes as the droplet generator simulation run in COMSOL Multiphysics version 5.1 software. In conclusion, the developed fabrication method promises simple, rapid, and strong bonding with sharp and clear micro-channel engraving.
  • Conference Object
    Evaluation of Anti-Inflammatory Potential and Lc-ms/Ms Analysis of Different Standards
    (Wiley, 2018) Sözmen, Alper Baran; Canbay, E.; Yıldırım Sözmen, Eser; Övez, Bikem
    Standardization of a LC-MS/MS method for phenolic compound content of biomass originated extracts was aimed in this study, Chlorella miniata extracts, which were cultivated solely for this study, were used for this purpose. The first step of the study was to compare external standard method, added standard method, and conventional standard method the qualitative identification of phenolic compounds of the extracts were performed by using LC-MS/MS system.