Multiplexed biosensing of proteins and virions with disposable plasmonic assays

Our growing ability to tailor healthcare to the needs of individuals has the potential to transform clinical treatment. However, the measurement of multiple biomarkers to inform clinical decisions requires rapid, effective, and affordable diagnostics. Chronic diseases and rapidly evolving pathogens in a larger population have also escalated the need for improved diagnostic capabilities. Current chemical diagnostics are often performed in centralized facilities and are still dependent on multiple steps, molecular labeling, and detailed analysis, causing the result turnaround time to be over hours and days. Rapid diagnostic kits based on lateral flow devices can return results quickly but are only capable of detecting a handful of pathogens or markers. Herein, we present the use of disposable plasmonics with chiroptical nanostructures as a platform for low-cost, label-free optical biosensing with multiplexing and without the need for flow systems often required in current optical biosensors. We showcase the detection of SARS-CoV-2 in complex media as well as an assay for the Norovirus and Zika virus as an early developmental milestone toward high-throughput, single-step diagnostic kits for differential diagnosis of multiple respiratory viruses and any other emerging diagnostic needs. Diagnostics based on this platform, which we term “disposable plasmonics assays,” would be suitable for low-cost screening of multiple pathogens or biomarkers in a near-point-of-care setting

3D printed tooling for injection moulded microfluidics

Microfluidics have been used for several decades to conduct a wide range of research in chemistry and the life sciences. The reduced dimensions of these devices give them advantages over classical analysis techniques such as increased sensitivity, shorter analysis times, and lower reagent consumption. However, current manufacturing processes for microfluidic chips either limits them to materials with unwanted properties, or are not cost effective enough for rapid-prototyping approaches. Here we show that inlays for injection moulding can be 3D printed, thus reducing the skills, cost, and time required for tool fabrication. We demonstrate the importance of orientation of the part during 3D printing so that features as small as 100 x 200 μm can be printed. We also demonstrate that the 3D printed inlay is durable enough to fabricate at least 500 parts. Furthermore, devices can be designed, manufactured, and tested within one working day. Finally, as demonstrators we design and mould a microfluidic chip to house a plasmonic biosensor as well as a device to house liver organoids showing how such chips can be used in organ-on-a-chip applications. This new fabrication technique bridges the gap between small production and industrial scale manufacturing, whilst making microfluidics cheaper, and more widely accessible