03 September 2010
Scientists in Australia have built a microneedle device capable of detecting disease-specific proteins directly from the skin.
Normally when a clinical sample such as blood is needed to screen a patient for disease, it has to be taken by a specially trained healthcare practitioner using a needle and syringe. The sample is then clotted, centrifuged and stored under controlled conditions ready for analysis.
Now Mark Kendall and his colleagues from the University of Queensland, Australia have found an alternative pain-free method which dispenses with invasive needles, specialist training and sample processing. Kendall incorporated a small chip coated with sharp, densely packed microneedles into a patch that can be applied to the skin. The sharp gold-coated silicon needles are less than 1 mm in length and are able to capture and sample protein antibodies directly from the skin.
Tiny silicon needles on the patch collect samples from the skin
Kendall and his team used their chip to detect anti-flu antibodies raised by mice vaccinated with a commercial flu vaccine. Their method has equivalent sensitivity to standard screening techniques but without the time-consuming processing steps required for blood samples or the need to dispose of sharps. 'The skin is a special organ for many reasons' says Kendall, 'it is abundant in immune cells and is also accessible, making it an attractive site for vaccination and sampling.'
Mark Prausnitz an expert in microneedles from Georgia Institute of Technology in Atlanta, US says the work is an important advance and that the patch 'could enable simple diagnostic tests that would otherwise require the pain and expertise of obtaining a blood sample.'
Having tested the Micropatch against flu-specific proteins, Kendall and his colleagues are now branching out to explore the detection of other diseases.