Here, we introduce an electricity-free centrifuge platform based on a manual centrifuge. The provided centrifugal force is sufficient to produce a plasma purity of 99 separated in as little as 2−3 min. We then performed an immunoassay on a paper devicethe results were observed by a portable reader. As a result, the detection limit of the C-Reactive Protein is 1 ng/mL, with a total turnaround time of 7 min.

Surface-enhanced Raman spectroscopy (SERS) is a useful analytical technique for detecting extremely small amounts of molecules. Herein, we designed a paper-based quasi-three-dimensional SERS substrate (P-SERS) that can provide potential to improve Raman analyses for food safety, pesticide poisoning, precision medicine, drug abuse and DNA/RNA testing. The sensitive, low-cost, flexible and disposable SERS substrate could be easily fabricated by physical deposition of gold nanoparticles array onto a filter paper. In this case, we are able to create non-continuous Au islands on the fiber surfaces, where the gaps between AuNPs can dramatically generate the high electric field to enhance Raman signal of target molecules.