Responsive Hydrogels for Label-Free Signal Transduction within Biosensors

Abstract

Hydrogels have found wide application in biosensors due to their versatile nature. This family of materials is applied in biosensing either to increase the loading capacity compared to two-dimensional surfaces, or to support biospecific hydrogel swelling occurring subsequent to specific recognition of an analyte. This review focuses on various principles underpinning the design of biospecific hydrogels acting through various molecular mechanisms in transducing the recognition event of label-free analytes. Towards this end, we describe several promising hydrogel systems that when combined with the appropriate readout platform and quantitative approach could lead to future real-life applications.

Release of Potassium Ion and Calcium Ion from Phosphorylcholine Group Bearing Hydrogels

“…Much of this attention is because of their high biocompatibility [5], attributed partially to their ability to imbibe large amounts of water [6], to mitigate denaturing protein adsorption, and because of their stimuli responsive nature [7], attributed partially to swelling-collapsing dynamics that are dependent on environmental conditions [8][9][10]. Because of the importance of diffusive transport in many aspects of molecular physiology, an area currently under investigation is the design and molecular engineering of the diffusive transport properties of small molecules and ions within the hydrogel matrix as a means towards control of expressed bioactivity.…”

Visual optical biosensors based on DNA-functionalized polyacrylamide hydrogels

“…Finally, various optical responses might be introduced into the gel, where the gel is used as a matrix for immobilization. These stimuli responsive gels are highly attractive for various applications including controlled drug release, sensing, switchable cell culture substrates and for flow control [21][22][23][24][25][26].…”

Future Applications of Electronic-Nose Technologies in Healthcare and Biomedicine

“…These polymeric materials provide a non-cytotoxic interface between the biosensor device and native living tissue or cell culture medium (Fonner et al, 2008). Gawel et al (2010) reviewed the various principles involved in the design of biospecific hydrogels acting through various molecular mechanisms to transduce the recognition of label-free analytes. The range of different responsive characteristics displayed by hydrogels include changes in equilibrium swelling volume in response to various changes in solution parameters such as solvent pH, ionic strength, temperature, electrical fields, and presence of surfactants.…”