The use of carbon nanotubes material in sensing applications for H1-antihistamine drugs

H 1 -antihistamines are pharmaceutical agents which act by blocking the action of histamine at the H 1 -receptor; prescribed for the treatment of allergic reactions and mast cell-related disorders. Although the administration of antihistamines is safe, sedation and other unwanted effects can occur mainly when the drug is taken in overdose. Thus, an important quality control is mandatory and voltammetric methods are highly recommended since they are very rapid and sensitive. Carbon nanotubes are well established carbon nanomaterials that have been used in the construction of electrochemical sensors due to their high conductivity, extensive surface area, and electrocatalysis properties. In this chapter, the use of carbon nanotubes in the development of voltammetric sensors for H 1 -antihistamine drugs will be presented and discussed. In the last decade, about 22 papers were found to report the construction and characterisation of voltammetric sensors employing single- or multi-walled carbon nanotubes with the objective of quantifying H 1 antihistamine drugs in several types of samples as pharmaceuticals, urine, and blood. The sensors were constructed by dropping aliquots of carbon nanotubes dispersion onto glassy carbon or screen-printed electrodes or by mixing carbon nanotubes powder with a binder (ionic liquid, paraffin, or mineral oil) to form a paste. The working electrodes based on carbon nanotubes provided electrocatalysed voltammetric signals with higher responses and less positive redox potential when compared to sensors without this nanomaterial.