Diagnosis Lab Image
The mesoporous biosensor helps detect breast cancer in its earliest stages. (Credit: Universitat Politècnica de València)

A prototype of a new biosensor helps detect breast cancer in its earliest stages. The biosensor falls within the field known as liquid biopsy, which helps detect the presence of cancer through a blood test. The low-cost mesoporous biosensor is easy to use and provides results in 30–60 minutes from a sample of the patient’s plasma.

The biosensor is composed of a nanomaterial — a nanoporous alumina — that facilitates the detection in plasma of miR-99a-5p microRNA, which is associated with breast cancer. Until now, this has been done by using complex and time-consuming techniques, which means that this system could not be used as a diagnostic tool in the clinical setting.

The nanopores of the biosensor are loaded with a dye — rhodamine B — and are sealed with an oligonucleotide. When interacting with the plasma sample, if the pore gates do not detect the presence of the microRNA, they remain closed; in contrast, in the presence of miR-99a-5p, the pore gates open and the dye is released.