Editor: Amanita Setari
Motivation behind the research
The goal of personalised medicine is to diagnose and treat patients based on their unique genetic profiles. Personalised diagnostics supersede the one-size-fits-all treatment approach by allowing clinicians to tailor their treatment to specific disease profiles, which can improve clinical outcomes for a variety of conditions. In recent years, there has been a growing emphasis on the importance of diagnostic tools capable of rapid diagnosis and early treatment intervention for both clinician-oriented and patient-oriented point-of-care (POC) use. Lab-on-a-chip (LOC) devices are ideal personalised diagnostics, which utilise microfluidics and nanotechnology to combine several laboratory procedures of disease detection into a single miniaturised platform. Despite the exciting potential that LOC devices offer for POC personalised diagnostics, the majority of LOC systems have faced difficulties in progressing to real-world products for practical application. The constraints that impede LOC commercialisation have been attributed to high fabrication costs, complex precision engineering, and difficulties controlling sophisticated fluid movement/biochemical reactions. These limitations have motivated our research group at the Australian Institute for Bioengineering & Nanotechnology to explore LOC alternatives for the emerging field of POC personalised diagnostics.
Our efforts over the last few years have resulted in the development of a solution-based lab-in-a-drop (LID) system, in which an entire laboratory-based diagnostics workflow could be miniaturised and integrated within a singular fluid droplet for point-of-care detection. Our “lab-in-a-drop (LID)” system downscales the analysis of DNA/RNA disease biomarkers from a single drop of sample and may allow for early, low-cost personalised diagnosis of diseases while avoiding the need for costly, precise engineering.
“Lab-in-a-drop”: A miniaturised, fabrication-free diagnostics platform, in which traditional bioassays are downsized into a droplet and programmed for convenient detection. Adapted with permission from Royal Society of Chemistry.
The traditional biosensing of nucleic acid (NA) (i.e., DNA/RNA) disease biomarkers from biological samples consists of three fundamental steps: (i) sample preparation (i.e., NA biomarker isolation/purification) from raw biological samples, such as blood, urine, or saliva; (ii) amplification of NA target copies to a detectable levels; and (iii) detection of target copies as a qualitative or quantitative readout signal. Thus far, our research efforts have allowed for the possibility of integrating these traditionally laboratory-based NA analysis steps (preparation, amplification, detection) into a miniaturised fluid droplet.
LID point-of-care diagnostics that are free from precision fabrication combine different laboratory-based nucleic acid analysis steps into a singular miniaturised platform. Adapted with permission from Royal Society of Chemistry.
Among several of our different lab-in-a-drop (LID) system abilities, we developed colourimetric and surface-enhanced Raman spectroscopy (SERS) systems, which are suitable for visual and multiplexed NA biomarker detection. A LID assay could be further developed for early diagnoses in the clinic, frequent individualised testing at home, or in the field for community healthcare purposes.
There are still several hurdles on the way to fully realising a LID system that can personalise diagnoses at the POC. The main challenge is the integration of a suitable sample preparation technique into the current format of the LID system.
It is our hope that advancements in the area of direct biological sampling (obtaining samples without any prior lysis and extraction) would prove to be significant progress towards the translation of LID technologies for clinical use. We also hope that progress will be made towards the realisation of a POC detection readout for quantitative analysis of several biomarkers at the same time. We expect that improvements to portable SERS instruments will be a possible solution to this problem.
Research Article: Enabling miniaturised personalised diagnostics: from lab-on-a-chip to lab-in-a-drop. Lab on a Chip, 2017.