Browsing by Author "Dag, Cagdas"

Now showing 1 - 2 of 2

Citation - WoS: 0
Citation - Scopus: 0
Microneedles With Interdigitated Electrodes for in Situ Impedimetric Vegf Sensing
(Wiley, 2025) Das, Ritu; Istif, Emin; Cebecioglu, Rumeysa; Ali, Mohsin; Atik, Yasin; Dag, Cagdas; Beker, Levent
Continuous monitoring of protein biomarkers in interstitial fluid (ISF) is essential for improving patient care and outcomes. This study presents a novel electrochemical impedance spectroscopy (EIS) sensor utilizing microneedles (MNs) patterned with interdigitated electrodes for the detection of vascular endothelial growth factor (VEGF). The MNs, are fabricated from flexible polylactide (PLA) using a simple molding technique, followed by metal deposition with an interdigitated pattern to serve as a platform for the EIS sensor. After functionalization with anti-VEGF antibodies, impedance measurements are conducted to detect VEGF levels, demonstrating a significant change in impedance in response to varying concentrations of the target biomarker. The MNs can easily penetrate rat skin by hand, puncturing without mechanical breakage. This innovative approach enhances the sensitivity and specificity of biomarker detection and paves the way for continuous monitoring applications in diagnostics and preventative medicine.
Citation - WoS: 36
Citation - Scopus: 35
Miniaturized Wireless Sensor Enables Real-Time Monitoring of Food Spoilage
(Nature Portfolio, 2023) Istif, Emin; Istıf, Emın; Mirzajani, Hadi; Dag, Cagdas; Mirlou, Fariborz; Ozuaciksoz, Elif Yaren; Cakir, Cengiz; Koydemir, Hatice Ceylan
Food spoilage results in food waste and food-borne diseases. Yet, standard laboratory tests to determine spoilage (mainly volatile biogenic amines) are not performed regularly by supply chain personnel or end customers. Here we developed a poly(styrene-co-maleic anhydride)-based, miniature (2 x 2 cm(2)) sensor for on-demand spoilage analysis via mobile phones. To demonstrate a real-life application, the wireless sensor was embedded into packaged chicken and beef; consecutive readings from meat samples using the sensor under various storage conditions enabled the monitoring of spoilage. While samples stored at room temperature showed an almost 700% change in sensor response on the third day, those stored in the freezer resulted in an insignificant change in sensor output. The proposed low-cost, miniature wireless sensor nodes can be integrated into packaged foods, helping consumers and suppliers detect spoilage of protein-rich foods on demand, and ultimately preventing food waste and food-borne diseases. Standard tests to determine food spoilage are costly and time consuming. A poly(styrene-co-maleic anhydride)-based sensor offers a low-cost alternative that can be linked to mobile phones for real-time spoilage analysis. The device was tested on chicken and beef samples under various storage conditions.