Disease Biomarker Detection

Early detection of cancer offers the prospect of better outcomes for patients. One way of detecting the presence of cancer is to look for signals called ‘biomarkers’ in samples of blood, urine or tissues.

One type of biomarker is called microRNA. When a person has cancer, it can affect the levels of specific versions of these small oligonucleotide molecules in the bloodstream. This offers a means of detecting cancer biomarkers through a blood test.

Dr Wenxin Wang’s group are creating a new way to detect small oligonucleotide molecules, such as mircoRNA, through a process called DNA hybridisation. To date, they have been able to detect specific sequences of small oligonucleotides in a model experiment carried out in a fraction of blood called serum.

Separately, the group have used a versatile DE-ATRP (Deactivation-Enhanced Atom Transfer Radical Polymerisation) method to make a specific polymer structure that can change physical properties in the presence of double-stranded DNA. They labelled the polymer and successfully used it to detect single-stranded DNA in serum1 (figure 1). 

Dr Wang also demonstrated the use of ATRP to graft a cationic polymer from cellulose paper. The group used it to detect DNA hybridisation in the nanomolar range (figure 2a, 2b). They expect that modifications to the system will increase the sensitivity for possible clinical application and disease diagnosis2.