Glass-based microfluidics in biosensing and bioassays: from fabrication techniques to application to bacteria detection

Glass-based microfluidic devices have emerged as powerful platforms for biosensing and bioassays due to their superior chemical resistance, optical transparency, and high thermal stability. Compared to inorganic, organic polymeric, and paper-based materials, glass offers superior mechanical robustness, precise microfabrication capabilities, and long-term stability. These properties make glass an ideal substrate for precise and reproducible bioanalytical applications, particularly in bacterial detection. This review provides an overview of the three main topics in glass-based microfluidic biosensing systems: fabrication, detection techniques and applications. The fabrication techniques including photolithography, laser micromachining, wet and dry etching, and bonding strategies are discussed. Furthermore, electrochemical and optical detection techniques in glass-based microfluidic biosensors are illustrated. Additionally, we explore the application of glass-based microfluidic systems in biosensing and bioassay platforms, highlighting their role in improving analytical performance through enhanced sensitivity, and stability. The application of glass-based microfluidic devices for bacterial sensing is critically examined, focusing on electrochemical and optical detection methods. Finally, we highlight the current challenges and future perspectives in advancing glass-based microfluidics for bacterial biosensing, emphasizing the need for scalable manufacturing, enhanced sensitivity, and improved portability. • Technological advances in microfluidic system development offer new and improved opportunities in bioassay applications. • Microfluidic devices, which can be easily integrated with biosensing systems and bioassays, have numerous advantages, among which reduced sample volume consumption is the most evident. • Transparency, chemical and biological compatibility and inferior thermal resistance are only some of the advantages provided by glass-based materials in microfluidics. • Microfluidic-integrated biosensing systems have received enhanced attention in the fields where detection of bacteria is most relevant, such as food safety and medical issues connected with drug-resistance.