Portable, low-cost, and quantitative nucleic acid detection is desirable for point-of-care diagnostics; however, current polymerase chain reaction testing often requires time-consuming multiple steps and costly equipment. We report an integrated microfluidic diagnostic device capable of on-site quantitative nucleic acid detection directly from the blood without separate sample preparation steps. First, we prepatterned the amplification initiator [magnesium acetate (MgOAc)] on the chip to enable digital nucleic acid amplification. Second, a simplified sample preparation step is demonstrated, where the plasma is separated autonomously into 224 microwells (100 nl per well) without any hemolysis. Furthermore, self-powered microfluidic pumping without any external pumps, controllers, or power sources is accomplished by an integrated vacuum battery on the chip. This simple chip allows rapid quantitative digital nucleic acid detection directly from human blood samples (10 to 105 copies of methicillin-resistant Staphylococcus aureus DNA per microliter, ~30 min, via isothermal recombinase polymerase amplification). These autonomous, portable, lab-on-chip technologies provide promising foundations for future low-cost molecular diagnostic assays.
Erh-Chia Yeh1,2, Chi-Cheng Fu1,2, Lucy Hu1, Rohan Thakur1, Jeffrey Feng1 and Luke P. Lee1,2,3,4,*
1Department of Bioengineering, University of California, Berkeley, Berkeley, CA 94720, USA.
2Berkeley Sensor and Actuator Center, University of California, Berkeley, Berkeley, CA 94720, USA.
3Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA 94720, USA.
4Biophysics Graduate Program, University of California, Berkeley, Berkeley, CA 94720, USA.
↵*Corresponding author. Email: email@example.com
Science Advances 22 Mar 2017:
Vol. 3, no. 3, e1501645