Optical thin-film biochips for multiplex detection of eight allergens in food

An innovative method for the rapid detection of food allergens is developed and validated. Here we reported the development of silicon-based optical thin-film biochip technology that simultaneously permits visible detection of eight food allergens including celery, almond, oat, sesame, mustard, lupine, walnut and hazelnut on the basis of two tetraplex PCR systems. The biochip detection time was about 30 min after PCR amplification. Briefly, the optical thin-film biochip detects the presence of PCR fragment targets by enzymatically converting the formation of nucleic acid hybrids to molecular thin films. The mass contributed by the thin film alters the interference pattern of light on the biochip surface, resulting in a visible color change on the chip surface. Therefore, this assay permits sensitive, specific and high-throughput detection of allergens in food samples.

► Eight food allergens can be amplified by two tetraplex PCR assays.
► Simultaneous detection of eight food allergens with optical thin-film biochips.
► The chips can detect PCR products from eight food allergens in a 30-min assay.
► Experimental results can be directly observed by the naked eye.