Microneedle technology has afforded human patients the benefits of painless injections and virtually The disposable patch collects plant pathogen DNA. Source: North Carolina State Universitynoninvasive monitoring of glucose and other interstitial fluids. The technology is now being extended to the detection of diseases in plants based on a patch device that could one day enable farmers to quickly diagnose different crop maladies in the field.

Researchers from University of California Los Angeles, Tianjin University (China) and North Carolina State University developed a rapid plant DNA extraction method using a disposable polymeric microneedle patch. The postage stamp-sized patch is composed of an inexpensive polymer, which is covered on one side with hundreds of tiny needles 0.8 mm long. The device is applied to a plant of interest for a few seconds, peeled off and then rinsed with a buffer solution to collect the genetic material.

The microneedle system was demonstrated to achieve a 100% detection rate of pathogen DNA associated with blight disease in tomato plants. Assay results were comparable to those documented for the more time-consuming gold standard cetyltrimethylammonium bromide-based DNA extraction method.

The researchers plan to refine the technology to realize a low-cost, portable DNA extraction and analysis system as an on-site plant disease detection tool.