Lung cancer is an extremely common malignant tumor

in which epidermal growth factor receptor(EGFR)is one of the key mutation targets.A micro-nano-sensing chip based on impedance analysis is developed for the requirement of rapid detection of the lung cancer mutation EGFR-L858R.The chip is monolithically fabricated using MEMS technology and consists of two parts:amicro-chamber and detection electrodes.The micro-reaction chamber for nuc

leic acid amplification is fabricated on silicon.A pair of interdigital electrodes are fabricated on the glass and an insulating Si

3

N

4

film is deposited on top.The sensingchip is formed by bonding the silicon to the glass.The performance of the proposed sensor is validated using KCl solutions with concentrations ranging from 0.1 to 0.5mmol/L.The result shows that the output impedance exhibits excellent linearity with the logarithm of the ion concentration(

R

2

=0.995).The sensor shows excellent repeatability and the relative standard deviation(RSD)is less than 2%.The impedance of polymerase chain reaction(PCR) process of EGFR-L858R gene in sample is monitored with the sensing chip.The negative and positive samples show a large impedance difference and the positive sample(10

6

copies/μL)is determined within 10min.Compared with fluorescence quantitative detection the developed sensor saves much detection time and shows a significant application value in field rapid detection.