The development of liquid biopsies, minimally invasive techniques, which analyze biomarkers in bodily fluids like blood, urine and saliva have opened new opportunities in disease detection (1).
Urine as a liquid biopsy has shown great promise as it is quick and non-clinician dependent. Additionally, urine can be collected in large quantities. However, even though urine contains useful and diagnostically relevant biomarkers, there are challenges with urine collection.
In order to maintain the integrity and original composition of urine samples in the period between collection and processing, the use of a urine preservative can be necessary (2).
Below are 3 reasons why urine preservation is needed:
#1 - Allows longer stability of DNA
The required stability of a urine sample depends greatly on the analysis to be performed. The addition of preservative allows substantially longer preservation of urine its content for diagnostic purposes.
Novosanis' Urine Conservation Medium (UCM) has shown to prevent degradation of Human Papillomavirus (HPV) DNA the primary cause of cervical cancer. A study showed that after 7 days of storage at room temperature, HPV16 was detected in all samples spiked with 1000 copies/µL of HPV16 plasmids where UCM was added, and only in 25% of the unpreserved samples (3).
#2 – Permits increased length of time between sampling and actual analysis
Unpreserved urine can result in metabolic changes, influencing the quality of the sample. Additionally, to avoid sample dilution, or insufficient preservation, the preservative to urine ratio should be ensured (4). Our data shows for UCM a 1:3 preservative to sample ratio for optimal preservation performance.
#3 - Offers opportunity for home collection
One of the key benefits of urine as a liquid biopsy in comparison to blood sampling is that it is absolutely non-invasive and does not require a clinician for sample collection. Additionally, in terms of analysis, the isolation of DNA from urine is in theory easier than blood, due to the low protein content after filtration in the kidney (5).
The combination of the Colli-Pee® platform with a preservative for urine stabilization can be gamechanging in the field of urine-based diagnostic testing.
To extend the preservation coverage to other analytes (RNA, EV, cfDNA) a new preservative, Urinary Analyte Stabilizer (UAS) is currently in development with our sister company DNA Genotek. Prototypes are available for evaluation purposes.