A rapid MZI-IDA sensor system for EGFR mutation testing in non-small cell lung cancer (NSCLC)

Epidermal growth factor receptor (EGFR) is a non-small-cell lung cancer biomarker, based on which several near-patient-testing methods have been developed and applied to predict treatment response on individual patients. Existing methods for detection of EGFR mutation are costly, labor-intensive and time-consuming. In this paper, we report a novel EGFR mutation testing system, which is based on Mach-Zehnder Interferometer (MZI) sensor and isothermal solid-phase DNA amplification (IDA) technique, called MZI-IDA sensor system. The system can deliver results within 30 min and shows high sensitivity to detect trace amounts of genomic DNA (<1 copy). In addition, the system is able to detect a L858R mutation in a 99:1 mixture of wild-type and mutant cells. In a pilot clinical study, the system is compared with conventional methods (PCR and direct sequencing) by using tissue biopsy samples from NSCLC patients. The MZI-IDA sensor system is proved to be capable of fast and accurate detection of the L858R mutation of EGFR gene in clinical samples. This may greatly help the clinicians develop an appropriate treatment plan.