Nanomaterials as versatile tools for signal amplification in (bio)analytical applications

• Recent advances in signal amplification strategies utilizing nanomaterials.
• Gold nanoparticles as versatile signal enhancement labels and enzyme carriers.
• Emerging nanomaterials and nanocomposites in (bio)analytical assays.

(Bio)analytical applications often require efficient signal enhancement strategies that are directly integrated into the biorecognition process. Nanomaterials are increasingly used for this purpose, as their small size provides numerous unique properties. This review identifies recent trends in (bio)analytical sensing and discusses the use of nanomaterials as signal enhancement tags and as carriers in enzymatic amplification enabling significantly higher performance compared to traditional assays. Gold nanoparticles are one of the most established amplification tools and still play a major role in the development of highly sensitive (bio)assays. These are based on signal enhancement for detection approaches that range from colorimetric over plasmonic and electrochemical to mass spectrometric systems. We also discuss the opportunities of other nanomaterials such as nanocomposites including carbon nanotubes and graphene, magnetite nanoparticles, polymeric nanomaterials, liposomes and quantum dots that are increasingly used in this field. Based on the observed trends, future perspectives in (bio)assay development are presented.