| Despite the substantial improvement of diagnostic technologies over the last few decades, the most advanced diagnostic tests are centralized, require expensive facilities and expertise, and are therefore inaccessible to many patients and healthcare professionals in resource-limited areas. Point-of-Care (POC) diagnostics, which emphasize the idea that medical tests are conducted near the patients and subsequently lead to rapid clinical decisions, aim to overcome these limitations by decentralizing simple and cost-effective diagnostic approaches. Advances in nanotechnology have also shown the potential to improve POC diagnostics by offering tunable optical, electrical and magnetic properties that can transduce signals or simplify diagnostic procedures. Nonetheless, many nanoparticle-based molecular assays have been limited to the investigation of synthetic targets due to low analytical sensitivity, and clinical validation of nanodiagnostics has not been thoroughly explored yet. The work presented herein explores the development of ultrasensitive nanoparticle-based POC diagnostic platforms. Specifically, Quantum Dot (QD) barcode and multicomponent nucleic acid enzyme-gold nanoparticle (MNAzyme-GNP) assays were incorporated with Recombinase Polymerase Amplification (RPA) to demonstrate multiplexed and colorimetric detections respectively, improve the detection limits, and present clinically relevant diagnosis of infectious diseases. Overall, the combined advantages of nanotechnology and isothermal nucleic acid amplification strategy provided highly sensitive and specific detection platforms that are promising for diagnosis of infectious diseases in resource-limited settings. |
