Liquid biopsy (LB) diagnostics can improve cancer treatment monitoring and personalization. There are currently pre-analytical challenges, which include 1) the need for skilled personnel to perform sample preparation, and 2) strict logistic requirements for sample transportation, often overseas. In the current LB workflows, plasma separation includes two critical centrifugation steps either at the sample collection site or in the clinical laboratory.
If the sample is prepared on-site, a dry-ice shipment is required. Alternatively, transportation of the sample as blood is complicated by the need for fast and temperature-controlled shipment, as the release of nucleic acids from white blood cells would destroy the LB sample.
Overall, manual preparation of plasma leaves the current process vulnerable to human errors and therefore an automated, standardized technology for plasma separation, DNA extraction, and quantitation is required.
Cell-free DNA (cfDNA) allows non-invasive analysis of cancer-causing genetic mutations. The low amount of cfDNA circulating in the blood of a healthy person originates from apoptotic blood cells. However, in case of cancer, tumor tissue is shedding short circulating tumor DNA (ctDNA) fragments, dependent on the tumor location and volume.
In our experience with ctDNA, mutated cancer DNA varies between 0.1-60% of the cfDNA of cancer patients. Measuring the amount and genetic/epigenetic changes in the ctDNA is a potential tool for determining the origin and the burden of cancer, and capturing new mutations appearing during targeted therapies. So far the access to this rich genetic and epigenetic information available in ctDNA has been prone to errors due to variable amounts and quality of the input material for analysis. The variation in sample quality is due to interference from genomic DNA, which is thousand times more frequent than cfDNA in the blood.
Sample transfer is a challenge for the global availability of liquid biopsy diagnostics. We are developing an automated extraction and transfer cartridge for blood-based biomarkers (DNA, RNA, cells, proteins) to better support frequent sample acquisition and analysis. Our goal is to facilitate the expansion of the global liquid biopsy diagnostics across borders and continents, independent of the laboratory workforce situation at the sample collection site or of the conditions of the sample transfer.