New Trends in Nanoclay-Modified Sensors

Abstract

Nanoclays are widespread materials characterized by a layered structure in the nano-scale range. They have multiple applications in diverse scientific and industrial areas, mainly due to their swelling capacity, cation exchange capacity, and plasticity. Due to the cation exchange capacity, nanoclays can serve as host matrices for the stabilization of several molecules and, thus, they can be used as sensors by incorporating electroactive ions, biomolecules as enzymes, or fluorescence probes. In this review, the most recent applications as bioanalyte sensors are addressed, focusing on two main detection systems: electrochemical and optical methods. Particularly, the application of electrochemical sensors with clay-modified electrodes (CLME) for pesticide detection is described. Moreover, recent advances of both electrochemical and optical sensors based on nanoclays for diverse bioanalytes’ detection such as glucose, H2O2, organic acids, proteins, or bacteria are also discussed. As it can be seen from this review, nanoclays can become a key factor in sensors’ development, creating an emerging technology for the detection of bioanalytes, with application in both environmental and biomedical fields.

Nanohybrid of Thymol and 2D Simonkolleite Enhances Inhibition of Bacterial Growth, Biofilm Formation, and Free Radicals

“…Micrographs depicted in Figure 7 c exhibit the typical hexagonal morphology (blue arrows) of layered compounds (at least one dimension in the nano-range order) [ 48 ]. In the hybrid ( Figure 7 d), it can be seen that the structure remained, but the size decreased, and the organic part surrounding the particle (yellow circles), in some cases, formed networks of ZnLHS and biomolecule.…”

Recent Point of Care (PoC) Electrochemical Testing Trends of New Diagnostics Platforms for Vitamin D

“…This is because fillers and nanoclays may independently shrink to nanoscale. [50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69] When looking for biocompatible, biodegradable, and non-toxic nano additives, nanoclays are a fantastic choice since, under the right dispersion conditions, they may be reduced to nanoscale by chemical processes and/ or extra mechanical pressures. The term "organoclays" refers to groups that have had their surfaces altered by organics.…”

“…[75] Today's and tomorrow's biomedical science faces a significant challenge in the development of a focused, accurate, and simple-to-use electrochemical analytical device for a variety of applications. [60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75] Anusha et al developed a fullerene-C 60 and copper-nickel bimetallic nanoparticle-based electrochemical sensor to accelerate vitamin D oxidation and measured its concentration in blood samples. Nanoparticles suggested using modified glassy carbon electrodes made of nanocomposite films.…”

A Polypyrrole/Nanoclay Hybrid Film for Ultra-Sensitive Cardiac Troponin T Electrochemical Immunosensor

“…Several nanostructured materials have been applied as support to chemical modification and biomolecules immobilization in electrochemical immunosensor, such as carbon nanotubes, graphene, nanowires, oxide/metal nanoparticles, and quantum dots [ 5 , 6 , 7 , 8 , 9 ]. A class of nanomaterials that has shown promising results is obtained from aluminosilicates, such as nanoclays (NCYs), which have been used to incorporate electroactive ions, biomolecules, and fluorescence compounds into the development of (bio)sensor devices [ 10 , 11 ]. NCY is a layered silicate clay mineral which consists of nanoplatelets with diameter of 50 e 200 nm in length and 1 nm in thickness [ 12 ].…”

“…NCY is a layered silicate clay mineral which consists of nanoplatelets with diameter of 50 e 200 nm in length and 1 nm in thickness [ 12 ]. Some properties of the NCYs make them suitable as electrode surface modifiers, such as their semiconductor properties, ionic exchange capacity, good catalytic support, large surface area, mechanical stability, porosity, low cost, and possibility to increase biocatalytic efficiency by reducing limitations diffusional [ 10 , 13 , 14 ].…”