A novel electrochemical sensor for capsaicin based on mesoporous cellular foams

Abstract

A novel electrochemical sensor for capsaicin using mesoporous cellular foams (MCFs) as sensitive material is reported. The high sensitivity of the proposed sensor is attributed to the strong adsorption of capsaicin by mesoporous cellular foams and large surface area of the working electrode resulting from MCFs modification.

Recent Trends on Electrochemical Sensors Based on Ordered Mesoporous Carbon

“…OMC materials by themselves are attractive electrode substrates for electrochemical sensing owing to their attractive properties (large conducting surface area, regular and widely open nanostructure, catalytic edge-plane-like sites, or oxygenated surface functions). Table 1 gathers all applications of unmodified OMC-based electrochemical sensors reported to date [ 23 , 25 , 43 , 44 , 45 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , <...>…”

“…Several drugs and biologically-relevant molecules, as well as some pesticides, have been detected after accumulation at OMC-modified electrodes. The preconcentration mechanism is not always described but it is possibly due to hydrophobic and/or π–π interactions as most of the investigated species possess aromatic moieties in their molecular structure (i.e., phenol [ 57 , 59 , 72 , 79 , 98 ], nitrophenyl or nitroaromatic groups [ 64 , 78 , 85 , 87 , 89 , 90 ], catechol [ 65 , 97 ], or other aromatic groups [ 60 , 96 , 99 ]). Due to the non-specific nature of these interactions, the sensor selectivity is expected to be rather poor (only controlled by the detection potential) and thus limited in real environmental monitoring (except for spiked samples) but useful to the analysis of drug formulations (pharmaceutical tablets) or foodstuffs, for instance.…”

“…These applications were mostly based on OMC film electrodes ( Table 1 ), but also on carbon paste [ 59 , 89 ] and ionic liquid-based carbon paste electrodes [ 57 , 60 , 65 , 92 , 97 ]. In this last case, the ionic liquid serves as a binder but it could also contribute to accumulate the target analyte.…”

Ion pairing based polyurethane foam sorbent packed column combined with inductively coupled plasma–optical emission spectrometry for sensitive determination and chemical speciation of bismuth(III & V) in water

“…Modified graphite chemically modified with gallic acid [24], Chitosan [25] and other solid sorbents [26] have been used for the removal and/or preconcentration of Bi from aqueous. In this scenario, PUF was considered as an interesting solid phase extractor (SPE) due to its large availability, chemical and thermal resistance and minimum manipulation requirements [27][28][29][30][31][32][33][34][35][36]. Polar and non polar groups in PUF facilitate retention of different classes of substances [27][28][29][30][31][32].…”

Improved Sensing of Capsaicin with TiO2 Nanoparticles Modified Epoxy Graphite Electrode

“…All these research use some modifiers in the electrode to improve the sensing of capsaicin. Variants described include boron‐doped diamond electrode ; carbon paste electrodes modified with amino‐functionalized mesoporous silica , mesoporous cellular foams , β‐cyclodextrin ; glassy carbon electrode ; glassy carbon electrode modified with graphene‐titania‐nafion composite film , ruthenium nanoparticles decorated carbon nanotubes platform , polypyrrole/Bi 2 O 3 /graphene oxide ; graphite pencil electrode ; single‐walled and multi walled carbon nanotubes based screen printed electrode ; screen printed electrode modified with Ag/Ag 2 O nanoparticles/reduced graphene oxide ; poly(sodium 4 styrenesulfonate) functionalized graphite ; paraffin‐impregnated graphite electrode ; polyaniline electrode ; biosensor based on a horseradish peroxidase enzyme‐capsaicin reaction mediated by ferrocene ; enzyme biosensor using ammonia‐lyase enzyme , etc. Mechanistic steps involved in the electrochemical reactions of capsaicin are shown in the Scheme .…”