文档介绍：Trends Trends in Analytical Chemistry, Vol. 24, No. 9, 2005
New materials for electrochemical
sensing VI: Carbon nanotubes
Arben Merkoc¸i, Martin Pumera, Xavier Llopis, Briza Pe´rez, Manel del Valle,
Salvador Alegret
Carbon nanotubes (CNTs) combine in a unique way high electrical conduc- chemical properties. There is increasing
tivity, high chemical stability and extremely high mechanical strength. These potential Ts to be used as field
special properties of both single-wall (SW) and multi-wall (MW) CNTs have emission devices [9], nanoscale transistors
attracted the interest of many researchers in the field of electrochemical [10], tips for scanning microscopy [11] or
sensors. This article demonstrates the latest advances and future trends ponents posite materials [12].
producing, modifying, characterizing and Ts into electro- CNTs are one of the monly
chemical sensing systems. used building blocks of nanotechnology.
CNTs can be either used as single probes after formation in situ or even With 100 times the tensile strength of
individually attached onto a proper transducing surface after synthesis. Both steel, thermal conductivity better than all
Ts and Ts can be used to modify several electrode surfaces in but the purest diamond, and electrical
either vertically oriented ‘‘nanotube forests’’ or even a non-oriented way. conductivity similar to copper, but with
They can be also used in sensors after mixing them with a polymer matrix to the ability to carry much higher currents,
posites. they are very interesting.
We discuss novel applications Ts in electrochemical sensors, CNTs include both single-walled and
including enzyme-based biosensors, DNA sensors and immunosensors, and multi-walled structures (Fig. 1). Single-
propose future challenges and applications. Ts (Ts) (Fig. 1A) comprise of
ª 2005 Elsevier Ltd. All rights reserved. a cylindrical graphite sheet of nanoscale
diameter capped by hemispherical ends.
Keywords: Amperometry; Carbon na