Synergetic Effects of Combined Nanomaterials for Biosensing Applications

Abstract

Nanomaterials have become essential components for the development of biosensors since such nanosized compounds were shown to clearly increase the analytical performance. The improvements are mainly related to an increased surface area, thus providing an enhanced accessibility for the analyte, the compound to be detected, to the receptor unit, the sensing element. Nanomaterials can also add value to biosensor devices due to their intrinsic physical or chemical properties and can even act as transducers for the signal capture. Among the vast amount of examples where nanomaterials demonstrate their superiority to bulk materials, the combination of different nano-objects with different characteristics can create phenomena which contribute to new or improved signal capture setups. These phenomena and their utility in biosensor devices are summarized in a non-exhaustive way where the principles behind these synergetic effects are emphasized.

Keywords: biosensors; carbon; energy transfer; hybrids; metals; nanomaterials; semiconductors.

Figure 1

Schematic presentation of an UCNP and its anti-stokes type emission (top) and their functioning as bioanalytical transducer using a nanosized quencher (left) or a fluorescent dye (right).

Figure 2

Illustration of QDs with different sizes and the related band gaps leading to different emission wavelengths after excitation with UV light.

Figure 3

Scheme of a multiplex sensing principle using QDs and quenchers.

Figure 4

Schematic illustration of SPR signal amplification after the biorecognition event using QD labeled biomarkers.

Figure 5

Principle of improved SPR signals after adsorption of a biomolecules using MoS₂ as intermittent layer between monolayer graphene and the gold surface.

Figure 6

Sketch of a carbon QD with its defined sp² domains isolated and surrounded with diamond- like carbon which is highly oxidized on the surface of the particle.