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The reversible assembly of β-cyclodextrin-functionalizedgold NPs (β-CD Au NPs) is studied on mixed self-assembled monolayer(SAM), formed by coadsorptionof redox-active ferrocenylalkylthiols and n-alkanethiolson gold surfaces. The surface coverage and spatial distribution ofthe β-CD Au NPs monolayer on the gold substrate are tuned bythe self-assembled monolayer composition. The binding and releaseof β-CD Au NPs to and from the SAMs modified surface are followedby surface plasmon resonance (SPR) spectroscopy. The redox state ofthe tethered ferrocene in binary SAMs controls the formation of thesupramolecular interaction between ferrocene moieties and β-CD-cappedAu NPs. As a result, the potential-induced uptake and release of β-CDAu NPs to and from the surface is accomplished. The competitive bindingof β-CD Au NPs with guest molecules in solution shifted theequilibrium of the complexation–decomplexation process involvingthe supramolecular interaction with the Fc-functionalized surface.The dual controlled assembly of β-CD Au NPs on the surface enabledto use two stimuli as inputs for logic gate activation; the couplingbetween the localized surface plasmon, associated with the Au NP,and the surface plasmon wave, associated with the thin metal surface,is implemented as readout signal for “AND” logic gateoperations. [ABSTRACT FROM AUTHOR]