As a way to replace conventional assays, the research team presented a new portable digital device for biosensing based on functionalized graphene that can be employed for any click-able application. The lab-on-a-chip technology called Click-A+Chip is designed for facile and rapid digital detection of azido-nor-leucine (ANL)-labeled proteomes present in minute amount of sample.

Studies of heterochronic parabiosis, where two animals of different ages are joined surgically, provided proof-of-principle results that systemic proteins have broad age-specific effects on tissue health and repair. In an effort to identify these systemic proteins, bio-orthogonal non-canonical amino acid tagging (BONCAT) is used to tag these proteins.

“Although BONCAT is a very powerful technology,” researchers said, “the challenges associated with its complexity including large starting material requirements and cost of ANL-labeled protein detection, such as modified Antibody Arrays and Mass Spectrometry, limit its application.”

Click-A+Chip is a graphene-based field effect biosensor which utilizes novel on-chip click-chemistry to specifically bind to ANL-labeled biomolecules. In this study, Click-A+Chip was utilized for the capture of ANL-labeled proteins transferred from young to old parabiotic mouse partners.

The research team was able to identify the young-derived ANL-labeled Lif-1 and Leptin in parabiotic systemic milieu, confirming previous data as well as providing novel findings on the relative levels of these factors in young versus old parabionts.