Can we diagnose the deadly diseases years before they occur?
Imagine you are fishing in a lake with only one fish… You would have to be very very lucky to be at the right place at the right time to catch it! Early stage disease diagnostics is a similar game: one has to catch a biomarker – a protein molecule floating inside our bodies that is a signature of a certain disease.
Finding the correct biomarkers helps us diagnose a disease and also which stage it is at. Diagnosing diseases at an early stage means that actions could be taken to prevent the disease becoming more severe. The challenge with early stage diagnosis is that the biomarker concentration in the body can be very low at early stages – similar to having one fish in a lake.
To complicate things further, these biomarkers are extremely small and it is hard to tell one type of biomarker from another by looking at them. However, we can weigh the biomarkers with extremely sensitive scales – cantilevers – weighing masses down to fractions of a picogram (trillion times lighter than a spoon of sugar!). Their working principle is very similar to an oscillating mass attached to a spring. By following the changes in the resonant frequency of the cantilever, we can estimate what is the amount of a biomarker of interest adhered to the sensor and understand whether it is within the norms of a healthy person.
In our laboratory, instead of making the cantilever surface attractive to a specific biomarker and ‘fishing’ it directly from water, we keep drying tiny amounts of solution until we catch the molecules we are looking for and measure their total dry mass.
This technique – dry mass sensing – is a new simple way to detect proteins and will find many applications in diagnostics and general protein science.
Department of Chemistry, Knowles Lab
NanoDTC PhD Student Cohort 2014
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