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Browsing by Author "Bayramoglu, Gulay"

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    Article
    Citation - WoS: 5
    Citation - Scopus: 6
    Aptamer-Based Magnetic Isolation and Specific Detection System for listeria Monocytogenes from Food Samples
    (Elsevier, 2024) Bayramoglu, Gulay; Ozalp, Veli Cengiz; Arica, Mehmet Yakup; Basic Sciences
    In this work, an aptamer-based magnetic system was designed for specific and rapid detection of Listeria monocytogenes in food samples. To prepare the selective magnetic system against the target bacterium, firstly, magnetic particles (Fe3O4) were coated with two hydrophilic polymer layers. The specific aptamer immobilized magnetic system efficiently captured L. monocytogenes cells in a competitive response time of approximately 10 min. The magnetic aptamer detection system was very specific to L. monocytogenes and had high selective, up to 97.6 % compared to the Listeria species (Listeria ivanovii, Listeria innocua, and Listeria seeligeri) and other bacteria species Escherichia coli, Staphylococcus aureus, and Basillus subtilus. The isolation and detection of L. monocytogenes from food samples using the presented method are fast and reliable. Moreover, another significant factor to be contemplated is the use of a few chemicals for detection, reducing the cost of analysis, and the results can be obtained within 18 h.
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    Article
    Citation - WoS: 10
    Citation - Scopus: 11
    Quartz Crystal Microbalance-Based Aptasensor Integrated With Magnetic Pre-Concentration System for Detection of listeria Monocytogenes in Food Samples
    (Springer Wien, 2024) Beyazit, Fatma; Arica, Mehmet Yakup; Acikgoz-Erkaya, Ilkay; Ozalp, Veli Cengiz; Bayramoglu, Gulay; Basic Sciences
    A fast and accurate identification of Listeria monocytogenes. A new quartz crystal microbalance (QCM) aptasensor was designed for the specific and rapid detection of L. monocytogenes. Before detection of the target bacterium from samples in the QCM aptasensor, a magnetic pre-enrichment system was used to eliminate any contaminant in the samples. The prepared magnetic system was characterized using ATR-FTIR, SEM, VSM, BET, and analytical methods. The saturation magnetization values of the Fe3O4, Fe3O4@PDA, and Fe3O4@PDA@DAPEG particles were 57.2, 40.8, and 36.4 emu/g, respectively. The same aptamer was also immobilized on the QCM crystal integrated into QCM flow cell and utilized to quantitatively detect L. monocytogenes cells from the samples. It was found that a specific aptamer-magnetic pre-concentration system efficiently captured L. monocytogenes cells in a short time (approximately 10 min). The Fe3O4@PDA@DA-PEG-Apt particles provided selective isolation of L. monocytogenes from the bacteria-spiked media up to 91.8%. The immobilized aptamer content of the magnetic particles was 5834 mu g/g using 500 ng Apt/mL. The QCM aptasensor showed a very high range of analytical performance to the target bacterium from 1.0 x 10(2) and 1.0 x 10(7) CFU/mL. The limit of detection (LOD) and limit of quantitation (LOQ) were 148 and 448 CFU/mL, respectively, from the feeding of the QCM aptasensor flow cell with the eluent of the magnetic pre-concentration system. The reproducibility of the aptasensor was more than 95%. The aptasensor was very specific to L. monocytogenes compared to the other Listeria species (i.e., L. ivanovii, L. innocua, and L. seeligeri) or other tested bacteria such as Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. The QCM aptasensor was regenerated with NaOH solution, and the system was reused many times.
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    Review
    Citation - WoS: 14
    Citation - Scopus: 13
    Real-Time Biosensing Bacteria and Virus With Quartz Crystal Microbalance: Recent Advances, Opportunities, and Challenges
    (Taylor & Francis inc, 2023) Bonyadi, Farzaneh; Kavruk, Murat; Ucak, Samet; Cetin, Barbaros; Bayramoglu, Gulay; Dursun, Ali D. D.; Ozalp, Veli C. C.; Nutrition and Dietetics; Basic Sciences
    Continuous monitoring of pathogens finds applications in environmental, medical, and food industry settings. Quartz crystal microbalance (QCM) is one of the promising methods for real-time detection of bacteria and viruses. QCM is a technology that utilizes piezoelectric principles to measure mass and is commonly used in detecting the mass of chemicals adhering to a surface. Due to its high sensitivity and rapid detection times, QCM biosensors have attracted considerable attention as a potential method for detecting infections early and tracking the course of diseases, making it a promising tool for global public health professionals in the fight against infectious diseases. This review first provides an overview of the QCM biosensing method, including its principle of operation, various recognition elements used in biosensor creation, and its limitations and then summarizes notable examples of QCM biosensors for pathogens, focusing on microfluidic magnetic separation techniques as a promising tool in the pretreatment of samples. The review explores the use of QCM sensors in detecting pathogens in various samples, such as food, wastewater, and biological samples. The review also discusses the use of magnetic nanoparticles for sample preparation in QCM biosensors and their integration into microfluidic devices for automated detection of pathogens and highlights the importance of accurate and sensitive detection methods for early diagnosis of infections and the need for point-of-care approaches to simplify and reduce the cost of operation.
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    Article
    Citation - WoS: 29
    Citation - Scopus: 35
    Surface Plasmon Resonance Aptasensor for Brucella Detection in Milk
    (Elsevier, 2022) Dursun, Ali D.; Borsa, Baris A.; Bayramoglu, Gulay; Arica, M. Yakup; Ozalp, Veli C.; Basic Sciences
    A Surface Plasmon Resonance (SPR) aptasensor was developed for the detection of Brucella melitensis (B. melitensis) in milk samples. Brucellosis is a bacterial zoonotic disease with global distribution caused mostly by contaminated milk or their products. Aptamers recognizing B. melitensis were selected following a whole bacteria-SELEX procedure. Two aptamers were chosen for high affinity and high specificity. The high affinity aptamer (B70 aptamer) was immobilized on the surface of magnetic silica core-shell nanoparticles for initial purification of the target bacteria cells from milk matrix. Another aptamer, highly specific for B. melitensis cells (B46 aptamer), was used to prepare SPR sensor chips for sensitive determination of Brucella in eluted samples from magnetic purification since direct injection of milk samples to SPR sensor chips is known for a high background unspecific signal. Thus, we integrated a quick and efficient magnetic isolation step for subsequent instant detection of B. melitensis contamination in one ml of milk sample by SPR with a LOD value as low as 27 +/- 11 cells.