Nanochannels hold great prospects in intelligent systems; however, current research focuses on the inner space of the nanochannel while the outer surface is rarely explored. Here, we report on a cooperation mode of the outer surface and inner space of the nanochannel using an integrated nanochannel-electrode (INCE) and its application as a separation–detection system for rapid and facile detection of foodborne bacteria. Unlike conventional nanochannel systems, the INCE integrates two electrodes as a sensitive electrochemical interface and the nanochannel itself as nanofilter, generating a novel separation–detection system. The system is examined in a biosensing strategy based on magnetic nanoparticles (MNPs). Salmonella typhimurium (St) is taken as the target due to its severe threat to human health and food safety. By electrochemically probing the MNPs–St complex themselves on the surface of INCE, this method eliminates the requirement on additional signal labels. The biosensor presents a linear detection range from 102 to 107 CFU mL–1 and a limit of detection of 50 CFU mL–1, being comparable or even better than those of analogues with complicated signal amplification designs. Moreover, the biosensor exhibits good specificity against four types of interfering bacteria. This concept may bring new insight into the development of nanochannel research and contribute a new way to the fields of separation and detection.

Finally, the boundedness of solutions for X and > in the governing equation of motion of the two dof nonlinear system considered in section 5 of reference [1], is crucial in arriving at equation (17) of reference [1]. The question, then, is: can one guarantee the boundedness of the responses of mdof nonlinear systems even if one can disregard the parametric random excitations? If the answer is a$rmative, the next logical question is: how? LETTERS TO THE EDITOR

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Nanochannel‐based confinement effect is a fascinating signal transduction strategy for high‐performance sensing, but only size confinement is focused on while other confinement effects are unexplored. Here, a highly integrated nanochannel‐electrodes chip (INEC) is created and a size/volume‐dual‐confinement enzyme catalysis model for rapid and sensitive bacteria detection is developed. The INEC, by directly sandwiching a nanochannel chip (60 µm in thickness) in nanoporous gold layers, creates a micro‐droplet‐based confinement electrochemical cell (CEC). The size confinement of nanochannel promotes the urease catalysis efficiency to generate more ions, while the volume confinement of CEC significantly enriches ions by restricting diffusion. As a result, the INEC‐based dual‐confinement effects benefit a synergetic enhancement of the catalytic signal. A 11‐times ion‐strength‐based impedance response is obtained within just 1 min when compared to the relevant open system. Combining this novel nanoconfinement effects with nanofiltration of INEC, a separation/signal amplification‐integrated sensing strategy is further developed for Salmonella typhimurium detection. The biosensor realizes facile, rapid (<20 min), and specific signal readout with a detection limit of 9 CFU mL−1 in culturing solution, superior to most reports. This work may create a new paradigm for studying nanoconfined processes and contribute a new signal transduction technique for trace analysis application.