Alloyed AuPt nanoframes loaded on h-BN nanosheets as an ingenious ultrasensitive near-infrared photoelectrochemical biosensor for accurate monitoring glucose in human tears

Photo-electro-chemical (PEC) glucose biosensor has recently attracted extensive attention due to the double advantages of both photocatalysis via photon energy utilization and electrocatalytic oxidation through extra electric field. Compared with previous shorter wavelength (violet-visible) light-induced PEC reaction, the anticipated near infrared (NIR, >-700 nm) excited PEC biosensor with multiple fascinating features should be more suitable for clinical diagnostic biology. Herein, we report an ingenious NIR-PEC biosensor by loading alloyed Au5Pt9 nanoframes on two dimensional (2D) hexagonal boron nitride (h-BN) nanosheets. The obtained hBN/Au5Pt9 nanoframes exhibit a remarkable higher NIR-PEC activity in comparison with other as-prepared hBN/AuPt references. The improved PEC performance is attributed to the enhanced synergetic coupling effect between Au5Pt9 nanoalloys and constitutionally stable h-BN that gives rise to a stronger absorbance capacity and pronounced localized surface plasmon resonance (LSPR) in visible-NIR region as well as high free-electron mobility of framework-like Au/Pt. Interestingly, the obtained h-BN/Au5Pt9 nanoframes excited by 808 nm NIR light provide superior PEC accuracy and sensitivity as compared to visible or other NIR light irradiation. Then, the novel 808 nm NIR-PEC biosensor was used for precise glucose monitoring in human tears with a detectable concentration of 0.03-100 mu M and a low detection limit of 0.406 nM. Undoubtedly, the proposed hBN/Au5Pt9 nanoframes as an appealing NIR-PEC glucose biosensor can possess greater potential values for practical glucose monitoring in biomedicine.

Automated summary

Photo-electro-chemical (PEC) glucose biosensors have recently gained extensive attention due to their dual advantages of utilizing photon energy for photocatalysis and extra electric field for electrocatalytic oxidation. A novel NIR-PEC biosensor was developed by loading alloyed Au5Pt9 nanoframes on 2D hexagonal boron nitride (h-BN) nanosheets, exhibiting higher activity and improved performance for glucose monitoring in human tears. The enhanced synergetic coupling effect between Au5Pt9 nanoalloys and h-BN, along with the superior PEC accuracy and sensitivity under 808 nm NIR light excitation, makes the proposed hBN/Au5Pt9 nanoframes a promising candidate for practical glucose monitoring in biomedicine.