SPR‐enhanced fluorescence and protein‐improved blood compatibility of quadruple core/shell nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@Protein

This study presents a quadruple core/shell nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@Protein with both excellent fluorescent property and blood compatibility. Surface‐plasma resonance (SPR) was utilised to enhance the fluorescence of europium (Eu 3+ ) complexes. In this situation, the fluorescence of Eu 3+ (tta) 3 Phen in the triple Ag@SiO 2 @Eu 3+ (tta) 3 Phen nanostructure is greatly enhanced. To increase the biocompatibility in blood, lysozyme was used to modify the surface of the above triple nanostructure to get the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme. Then, through the clinical anti‐coagulation tests in human blood, the blood compatibility of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme is largely improved comparing with the triple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen, and the values of PT‐S, APTT‐S, TT‐S, and AT‐III of quadruple nanostructure blood sample with the modification of protein have the high correlation coefficients, 0.993–0.994, which means that the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme is close to the anti‐coagulation property of physiological saline state (0.9% NaCl aqueous solution). Thus, this work provides two key properties of the quadruple nanostructure of Ag@SiO 2 @Eu 3+ (tta) 3 Phen@lysozyme: the excellent fluorescence and the outstanding blood compatibility. This nanomaterial can be applied to bio‐imaging and bio‐sensing in blood.