▎ 摘　　要

NOVELTY - Biosensor comprises (a) reduced graphene oxide (rGO), and (b) nucleic acid probe absorbed on the rGO, where the nucleic acid probe comprises rolling circle amplification (RCA) primer sequence linked to a recognition moiety for an analyte. USE - The biosensor is useful in kit for detecting analyte chosen from nucleic acid, protein, and small molecule (all claimed). ADVANTAGE - The biosensor does not require equipment for detecting analyte, and detects analyte in an sensitive manner. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) kit for detection of an analyte, comprising (a) biosensor, (b) circular template comprising a sequence that is complementary to RCA primer sequence, (c) one or more RCA reagents, and optionally (iv) instructions for use; and (2) method for detection of an analyte, involves (a) contacting a sample suspected of comprising the analyte with biosensor under conditions for binding the analyte to the recognition moiety and desorption of the nucleic acid probe from the rGO, to provide rGO and an analyte-nucleic acid probe complex, (b) separating the rGO from the analyte-nucleic acid probe complex, (c) contacting the analyte-nucleic acid probe with a circular template comprising a sequence that is complementary to the RCA primer sequence under RCA conditions to amplify the circular template, and (d) detecting a presence or an absence of the amplified circular template, where the presence of the amplified circular template indicates presence of the analyte in the sample.