Pure-sal and rnapro-sal saliva collection devices for cell-free nucleic acid isolation in molecular diagnostics

Overview

Pure-SAL and RNAPro-SAL are saliva specimen collection devices designed to solve a persistent challenge in molecular diagnostics: contamination of samples by mucins, cells, and genomic DNA that can interfere with sensitive downstream assays. By using inert absorbent materials and size-exclusion principles, the devices capture between 1.2 and 1.6 mL of saliva in five minutes or less, passively and without the need for powered equipment. A built-in volume adequacy indicator signals when collection is complete, making the process simple enough for home-based or point-of-care use. The resulting specimen is rich in cell-free DNA (cfDNA), cell-free RNA (cfRNA), and exosomes, while cells and genomic DNA remain bound to the absorbent pad and can be independently released if needed.

Technical specifications

Key features:

• Passive saliva collection of 1.2–1.6 mL in under five minutes using inert absorbent materials
• Integrated sample volume adequacy indicator for reliable collection
• Size-exclusion filtration through a compression tube that removes mucins, cells, and genomic DNA
• Absorbent pad retains cells and gDNA, which can be released separately using dedicated reagents
• Delivers purified saliva enriched in cfDNA, cfRNA, and exosomes
• Compatible with downstream molecular tests and rapid antigen or antibody assays
• Validated in three peer-reviewed publications in collaboration with the National Cancer Institute and UCLA for detection of lung cancer mutations (L858R and exon-19 deletion) using the EFIRM platform, with results correlating better to tissue biopsy than plasma or blood
• Both devices are commercially available and have been on the market for several years

Technology readiness level

Pure-SAL and RNAPro-SAL are commercially available products that have been on the market for several years. Their performance has been validated in multiple peer-reviewed publications, most notably in studies conducted by the National Cancer Institute in collaboration with UCLA, demonstrating clinical-grade sensitivity and specificity for lung cancer mutation detection in as little as 30 minutes. Ongoing research at external laboratories continues to expand the range of applications for these technologies across additional molecular and rapid diagnostic workflows.