All on size-coded single bead set: a modular enrich-amplify-amplify strategy for attomolar level multi-immunoassay.
Desheng ChenXiaobo ZhangLiping ZhuChenghui LiuZhengping LiPublished in: Chemical science (2022)
Ultrasensitive protein analysis is of great significance for early diagnosis and biological studies. The core challenge is that many critical protein markers at extremely low aM to fM levels are difficult to accurately quantify because the target-induced weak signal may be easily masked by the surrounding background. Hence, we propose herein an ultrasensitive immunoassay based on a modular Single Bead Enrich-Amplify-Amplify (SBEAA) strategy. The highly efficient enrichment of targets on only a single bead (enrich) could confine the target-responsive signal output within a limited tiny space. Furthermore, a cascade tyramide signal amplification design enables remarkable in situ signal enhancement just affixed to the target. As a result, the efficient but space-confined fluorescence deposition on a single bead will significantly exceed the background and provide a wide dynamic range. Importantly, the SBEAA system can be modularly combined to meet different levels of clinical need regarding the detection sensitivity from aM to nM. Finally, a size-coded SBEAA set (SC-SBEAA) is also designed that allows ultrasensitive multi-immunoassay for rare samples in a single tube.
Keyphrases
- label free
- highly efficient
- gold nanoparticles
- quantum dots
- sensitive detection
- molecularly imprinted
- protein protein
- binding protein
- small molecule
- single molecule
- drug delivery
- high glucose
- cancer therapy
- drug induced
- oxidative stress
- high resolution
- loop mediated isothermal amplification
- nucleic acid
- simultaneous determination
- liquid chromatography