Lab in a drop

Lab-on-a-chip to the extreme: pocket-sized PCR rapid test including sample preparation

Surface-functionalized superparamagnetic particles emulsified in mineral oil turn a free-standing droplet into a flexible virtual laboratory with (sub)microliter volumes. By using magnetic forces, rare acute monocytic leukaemia cells are extracted... Click here for more information.

This release is available in German.

Analysis and diagnosis in a chip format are coming of age, but their practical application has been limited because until now, the sample usually had to be prepared separately and on a nonminiaturized scale. Jürgen Pipper and his team at the Institute of Bioengineering and Nanotechnology in Singapore want to change this. They have now developed a rapid test for genetic diagnosis that combines the preparation of biological samples with a polymerase chain reaction (PCR) on one chip. As they report in the journal Angewandte Chemie, the “laboratory device” for all steps in this system is a single drop containing magnetic nanoparticles, which is moved across the chip by a magnetic field.

PCR allows gene sequences to be duplicated and identified—to identify a disease trigger, for example. In this process, the sample must cycle through a specific sequence of temperatures. Because of the slow heating and cooling processes, laboratory PCR usually takes several hours. The new chip PCR requires only minutes, including for the sample preparation.