[a] 1IntroductionChemically modified electrodes [1] have been extensively developed from 1970-80s [2][3][4],m ostly for electrocatalytic applications.E xtending chemicals ystems associated with electrode surfaces to complexb iomolecular assemblies resulted in bioelectrocatalytic systems [5,6] particularly usedi ne lectrochemical biosensors [7][8][9] and biofuel cells [10][11][12].N ew applications required novel adaptive properties of electrochemicals ystems which have been realizedi nm odified electrodes functionalized with various signal-responsive materials [13,14] [29].I n the mosts ophisticated systems, the activity of switchable electrodes was controlled by complexm ulti-enzymes ystems,b eing reversibly activated-inactivated by various patterns of different biochemicals added to solutions [30][31][32],t hus mimickingb iological regulative and adaptive properties.F urther advances in the design of novel bioelectrochemical and bioelectronic systemsw ere achieved with the use of biomolecular-functionalized nano-species (nanoparticles,c arbon nanotubes,e tc.) [33][34][35].T he use of magnetic micro/nano-species( e.g.,n anoparticles,n anorods,n anosheets) [36][37][38][39][40]w as particularly important for the development of novel magneto-switchable electrodes with unique and unusual properties [25-28, 41, 42].Thep resent article overviews shortly various electrochemical systems with switchable features controlled by external magnetic field and basedo nm agnetic micro/ nano-species.A pplying magnetic field to magnetics pecies with redox, electrocatalytic or bioelectrocatalytic properties and moving them arounda llowed their different arrangements on electrode surfaces,t hus changing the electrochemical responses,s witchingt hem ON and OFF and resulting in many interestingf eatures.W hile the exact description of the exemplified systemsc an be found in the original research papers,the presentr ichly illustrated article aims at the concept explanationst os ummarize the fieldd evelopments up to date.
2Lateral TranslocationofM agnetic Micro/NanoSpecies on Electrodes and Electrode ArraysOne of the first examplesofthe magneto-switchable bioelectrochemicals ystems was basedo nalateralt ranslocation of DNA-functionalized magnetic microspheres (super-paramagnetic polystyrene beads,c a. 1 mm, with included Fe 3 O 4 nanoparticles) alonga ne lectrodea rray composed of two conducting areas ("left"a nd "right" electrodes), both with the applied potential capable of oxidizing DNAm olecules [43],F igure1.T he magnetic microspheres chemically modified with DNAo ligomers (GGC CGA CTC ACTG CG CGT CTT CTG TCC CGC Abstract:T his article is an overview of extensive research efforts in many laboratories in the last two decades in the area of magneto-switchable electrochemicals ystems. Electrochemical reactions, including electrocatalytic and bioelectrocatalytic processes,h ave been reversibly activated and inhibited upon physical translocation and reorientation of differentm agnetic micro/nano-species on electrode surfaces,p artic...
