2025 Development of a QCM-D-Based Aptasensor for the Real-Time Detection of β-Lactoglobulin

Authors:
Tuba Çanak-Ipek, Melis Güler Girbas, Nicolas Casadei, Christian Schlensak, Anna-Kristina Marel and Meltem Avci-Adali

Journal:
Cell Biomaterials1, 100019. doi.org/10.1016/j.celbio.2025.100019

Institute:

Department of Thoracic and Cardiovascular Surgery, University Hospital Tübingen, 72076 Tübingen, Germany
Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany
NGS Competence Center Tübingen, University of Tübingen, 72076 Tübingen, Germany
Department of Food Technology and Bioprocess Engineering, Max Rubner-Institute, Federal Research Institute of Nutrition and Food, 76131 Karlsruhe, Germany

Abstract:
The prevalence of food allergies has been steadily increasing in recent years. β-lactoglobulin (β-LG), the main allergenic protein of milk and dairy allergies, is more commonly observed in infants and children. In this study, a β-LG-specific aptamer was selected using the combinatorial chemistry process known as systematic evolution of ligands by exponential enrichment (SELEX), and a quartz crystal microbalance with dissipation monitoring (QCM-D)-based aptasensor was developed using a novel surface functionalization technique, which mimics an artificial cell membrane on the QCM-D sensor surface, creating a physiologically relevant environment for the binding of the target to the sensor. Through SELEX combined with next-generation sequencing (NGS), the aptamer Apt 356 was identified. Its binding to β-LG was confirmed via dot blot analysis. The selected Apt 356 was then used for the development of a QCM-D-based sensor. To fabricate the sensor, the quartz surface was functionalized with a supported lipid bilayer (SLB). The β-LG-specific aptamer was immobilized onto this SLB. The results demonstrated that the QCM-D system allows real-time observation and evaluation of the binding of β-LG. While there have been some studies on aptasensors for the β-LG protein, to the best of our knowledge, this is the first QCM-D-based aptasensor developed specifically for β-LG protein detection.