Toward point-of-care diagnostics with consumer electronic devices: the expanding role of nanoparticles

There is a critical need for point-of-care (POC) diagnostics in health care and a parallel need for similar point-of-need (PON) diagnostics in other sectors. Such technology could have a profoundly positive impact on health, wellness and quality-of-life in both the developed and developing worlds. This very active area of research is converging with another very active area of research-the biomedical applications of nanotechnology-with exciting outcomes. In this review, we describe how nanoparticles facilitate the use of mass-produced consumer electronic devices for POC/PON diagnostic applications. We first highlight the growing need for POC diagnostics; provide a brief overview of clinical tests, biomarkers and lateral flow assays; describe the amenability of consumer electronic devices to POC/ PON diagnostics; and summarize the attractive properties of nanoparticle materials in these contexts. Devices of interest include cell phones, smartphones, wearable technology, other CMOS imaging devices, scanners, optical drives/disc players, and strip readers. We continue to describe how nanoparticles can enable and enhance the readout of diagnostic assays with these consumer electronic devices using illustrative examples from the literature. The most utilized nanoparticles include gold nanoparticles, carbon nanoparticles, quantum dots, upconversion nanoparticles, polymer or silica nanoparticle composites with other materials, and viral nanoparticles. Given that assays combining the foregoing nanoparticles with consumer electronic devices have almost exclusively utilized optical readout, we further assess the potential for developing nanoparticle-based electrochemical assays with readout through either a smartphone or personal blood glucose meter (for non-glucose biomarkers). The review concludes with our perspective on future research and development in this area, including the role nanoparticles may play in facilitating the emergence of the smartphone as a leading personal health care device.