Hydrogel-innovated nanotechnologies for chemical and biological analysis

In the past decades, nanomaterials and their derived technologies have been numerously improved for superior chemical and biological analysis. Those findings also overcame a few huge and important analysis issues about environmental and food safety monitoring as well as disease diagnosis. Nevertheless, so far, there are still a few intrinsic drawbacks and restrictions which are gradually being exposed when nanomaterials are applied in practical applications, such as synthesis and use complexity, low stabilities, weak anti-interference, limited sensitivity, and lacks of practicality. The substantial progresses of nanotechnology-based sensors, especially in terms of their practical uses, were seriously restricted. Recently, an increasing number of research works have indicated that with suitable and oriented integration of nanotechnologies, hydrogels equipped with their intriguing structures and high-performance chemical properties are suggested to be comparable helpers or supporters for these improved and high-reliability chem/bio-sensing uses. So far, even hydrogel and nanomaterials topics have attracted numerous attentions in chemical and biological analysis, the detailed introduction about the sensing function and interaction routes of hydrogel-involved nanotechnologies has not been presented in any review articles. In this review, the merits of hydrogels in the enhancement roles of nanotechnologies are remarkably highlighted. Additionally, hydrogel-based hybrid protocols which are combined with emerging nanomaterials and advanced nanotechnologies are comprehensively introduced and it systematically summaries the developed chem/bio-analysis, including their applications in optical, electrochemical, enhanced Raman analysis and electric device-based sensors. To further motivate the progress, the characteristics of hydrogels with the improvement points of nanotechnologies have been remarkably discussed, inspiring great possibilities in those significant areas of eco-environmental sustainability, human health protection, and food safety.