Three‐Dimensional Ribbon‐Like Gold Nanoparticle Assemblies on MXene for Detection of Creatinine by Surface‐Enhanced Raman Scattering

Creatinine is an important indicator of renal function, and its accurate and efficient detection is important to clinical diagnosis and disease monitoring. As the structure combining MXene layers and gold nanoparticles (AuNPs) provides many active sites and hot spots for surface-enhanced Raman scattering (SERS), ultrasensitive detection of creatinine can be realized. Herein, homogeneous ultrathin Ti₃C₂-MXene films are produced on a large scale by interfacial self-assembly, and a uniformly distributed AuNP monolayer and three-dimensional ribbon-like AuNP assemblies (RAuNPs) are then separately assembled on the MXene surface by simply regulating the nanoparticle concentration and the drying temperature. The two SERS substrates of AuNPs/MXene and RAuNPs/MXene are capable of sensitive detection of creatinine in aqueous solutions without labels. The SERS activity is verified using Rhodamine 6G (R6G). In the SERS detection of creatinine, the AuNPs/MXene substrate shows a linear range from 1 × 10^-4 to 1 × 10^-8 M with a limit of detection (LOD) of 287 nM, whereas the RAuNPs/MXene substrate exhibits a good linear relationship in the range from 1 × 10^-3 to 1 × 10^-10 M with a LOD of 2.64 nM. The outstanding SERS properties of RAuNPs/MXene suggest promising potential pertaining to the rapid and sensitive detection of creatinine.