Carbon Pastes and Carbon Paste Electrodes - Electroanalysis with Carbon Paste Electrodes - page 39

In.this.direction,.quite.a.large.effort.was.made.by.the.authors.of.this.topic,.having.proposed.a.whole.
series.of.various.CPE-holders,.assisting.their.proper.manufacturing.since.the.mid-1980s..The.genesis.
of.the.individual.constructions.in.our.workshops.is.depicted.in.Figure.2.10,.presenting.all.important.
designs.of.the.piston-operated.carbon.paste.holders.and.assemblies.appearing.as.time.went.by.
After.a.provisory.use.of.a.small.syringe.with.cut-off.end-tip.[537],.the.irst.piston-driven.body.
(image. “A”). was. machined. from. Telon. according. to. Monien.. Its. weakness. was. thread. carved.
directly.into.the.soft.plastic.and,.mainly,.the.piston.itself.made.of.ordinary.steel.and.thus.suscep-
tible.to.corrosion..The.second.design.(image.“B”).had.the.main.body.machined.from.much.harder.
plastic.mass.(Silon ® ).with.more.resistant.thread,.as.well.as.with.piston.from.a.noble.stainless.steel..
This somewhat.robust.holder.(“thick”.or.“T”.type.[540]).came.as.a.special.electrode.kit.devised.with.
exchangeable.thread-devised.endings.(caps).machined.again.from.Telon.and.having.four.different.
end.holes.allowing.one.to.select.three.different.electrode.diameters.for.voltammetric.experiments.
(1,.2,.or.3.mm),.or.even.a.“huge”.surface.(with.diameter.up.to.10.mm).for.some.potentiometric.or.
coulometric.measurements.[541]..Later.on,.in.the.early.1990s.[56,153],.the.function.of.thread.in.the.
Silon.corpus.was.improved.by.a.special.stainless.steel.inset.with.contra.thread..Meanwhile,.how-
ever,.the.Silon.material.itself.had.been.found.inapplicable.in.some.particularly.aggressive.chemicals.
(see.a.note.in.Section.2.1.3).and.the.next.series.of.plastic.bodies.were.again.machined.wholly.from.
Telon..The.resultant.CP-holders.(“C”).were.notably.thinner.and,.in.overall,.less.robust.compared.to.

(1)

(2)

2 cm 2 cm

(A)

(B)

2 cm

(C) (D)

FIGURE 2.10 Piston-driven. carbon. paste. holders. and. the. individual. construction. variants.. (A). First. pro-
totype.(with.two.spare.end.tips.and.the.connecting.cable),.detail.on.the.right:.end.tip.prior.to.(1).and.after.
extrusion. of. carbon. paste. (2);. (B). the. “T”. type:. disassembled. (above). and. assembled. body,. with. a. set. of.
exchangeable.end.tips.(right),.and.accessories.for.illing.with.carbon.paste.and.cleaning.(left);.(C).“S”.type:.
disassembled.(above).and.assembled.body,.with.a.set.of.tools.for.pressing.the.paste.(right.and.bottom).and.
illing.(a.spatula.on.top);.(D).“M”.type:.disassembled.(left).and.assembled.body,.with.an.ofice.ruler.as.a.mea-
sure..( Note :.All.constructions.presented.are.the.designs.used.by.the.authors.(Ivan.Švancara.and.Karel.Vytˇas),.
being.the.property.of.the.University.of.Pardubice,.Pardubice,.Czech.Republic.variants.“T”.and.“S,”.including.
principal.construction.elements.of.the.“M,”.are.the.patented.material.[544])..(Photos.from.authors'.archives.)