Reactive Blade-Coating Method for High-Throughput Synthesis and Film Formation of Gold Nanoparticles for Applications in Biomedical Sensing

Metallic nanoparticle-based thin films are utilized in a variety of applications, including catalysis, printed electronics, chemical and biological detection, and smart packaging. Due to their outstanding chemical, physical, and optical capabilities, gold nanoparticles (AuNPs) have been widely developed for these uses. AuNP-based thin films and devices have been fabricated using various techniques involving sophisticated manufacturing equipment such as mechanical milling, vacuum-based deposition, and lithography. Such methods are, however, relatively complex and are used only in pricey device applications or on very small samples. In contrast, solution-based approaches can offer a more straightforward and affordable strategy that can be used for large-scale production. In this study, a simple in situ reduction-based reactive blade-coating technique that is suitable for roll-to-roll production has been developed for the manufacture of AuNP thin films on rigid and flexible substrates. By varying the concentration of the reactants and the solvent systems, we are able to fabricate AuNP thin films in a variety of sizes and forms (morphologies). The AuNP thin film on glass, prepared using our approach, shows preliminary promising results for glucose detection. This approach facilitates the development of flexible and printable AuNP-based platforms with lower manufacturing costs for use in electrical, chemical, and medicinal applications.