Carbon Pastes and Carbon Paste Electrodes - Electroanalysis with Carbon Paste Electrodes - page 46

Honeycomb/colander
carbon paste electrode

1

2
3
4

1. Syringe-made corpus
2. Syringe piston
3. Wire (contact)
4. Holes (filled with CP)
5. PTFE plate
6. Fixing

5

6

Detail: 4

(A)

Electrode wheel
with filled holes

Rotating wheel
electrode

Reference
electrode

Electric
contact

Micro-switch
wheel system

Plexiglass
stand
(support)

Drive
shaft

Vessel with
sample solution

To
potentiostat Micro
switch

To timing device

(B)

FIGURE 2.14 Schematic. constructions. of. two. unusual. carbon. paste. electrodes.. (A). Honeycomb. carbon.
paste.electrode.(Newly.sketched.after.Yao,.C.-L..et.al.,. Anal. Chem .,.61,.279,.1989):.see.inscription;.(B).rotat-
ing.wheel.electrode.(Redrawn.and.rearranged.from.Lawrence,.R.J..and.Chambers,.J.A.,. Anal. Chem .,.39,.134,.
1967):.see.inscription..(From.authors'.archives.)

of.liquid.mercury,.the.whole.assembly.had.to.be.arranged.in.a.reverse.coniguration,.that.is,.with.
the.carbon.paste.surface.turned.upside..Despite.this.or,.rather,.thanks.to.this,.the.CPUE.has.been.
described.as.quite.practical.for.use.
A.loose.adaptation.of.a.CP-microelectrode.array.is.the.design.of.a.CMCPE.shown.in.Figure.2.14.
(Scheme. “A”). and. is. reported. to. offer. particularly. large. and. easy-to-renew. surface. [526].. The. tubu-
lar.corpus.of.this.CPE.was.made.from.a.disposable.syringe.by.cutting.its.end.tip.and.connecting.the.
obtained.tube.to.a. Telon ® .plate.with.44.holes.in.a.honeycomb.arrangement..The.carbon.paste.modiied.
with. electroactive. compound. of. interest. was. then. packed. into. the. hollow. tube. and—upon. request—
extruded.through.all.the.holes..Freshly.renewed.surface.of.this.CMCPE.whose.working.site.resembles.
also.a.colander.(kitchen.sieve).could.be.obtained.by.joint.polishing.of.all.miniature.carbon.paste.discs.
Probably.the.most.curious.design.of.a.CPE.ever.proposed.was.a.(carbon.paste).rotating.wheel.
electrode.(CP-RWE;.[27]),.looking.like.a.miniature.water.mill.(Figure.2.14,.Scheme.“B”)..Its.func-
tion.relies.on.a.large.wheel.consisting.of.24.holes.drilled.around.the.periphery.and.each.being.illed.