Bioinspired Turing-Nanoarchitected Needle for Solid Matrices Analysis: A Universal Platform Enabling Dual-Scale SERS Enhancement.

Abstract

The spontaneous emergence of Turing patterns in biological systems has inspired advanced materials with superior performance, yet their untapped potential in surface-enhanced Raman spectroscopy (SERS) technology offers a transformative frontier. Mirroring the anti-reflective coating of insect eyes, where Turing-patterned corneal protrusions form graded refractive index interfaces with the lens, a bioinspired integration of Turing-nanoarchitected Ag (TN-Ag) with in situ zeolitic imidazolate framework-8 (ZIF-8) growth is engineered. The electrochemically sculpted fractal framework on silver needles serves dual roles as plasmonic amplifiers and curvature-guided templates for ZIF-8 growth, spatially aligning electromagnetic hotspots with selective-enrichment porous channels. The TN-Ag/ZIF-8 hierarchical architecture enables dual-scale SERS enhancement through mesoscopic light modulation via refractive index gradients and microscopic molecular enrichment through size-selective pores. Leveraging 4-mercaptophenylboronic acid as a dual-recognition probe, this platform achieves ultrasensitive discrimination and detection of Hg²⁺ (10^-10 m) and methylmercury (10^-8 m) with exceptional interference resistance and practical reliability. Further, its injector-integrated design permits direct sampling in untreated solid matrices while seamlessly interfacing with portable Raman systems, demonstrating readiness for real-world environmental monitoring and food safety diagnostics. By transmuting biomimetic principles into functional nanofabrication, this work establishes a universal paradigm for next-generation on-site chemical analysis, uniting biological design logic with engineered sensing demands.