MXene nanosheet loaded gold nanocluster catalytic amplification-aptamer SERS quantitative assay platform for isocarbophos.

The traditional preparation of MXeneTi ₃ C ₂ is complicated. Two-dimensional MXeneTi ₃ C ₂ nanosheets were prepared via in-situ generation of HF etching Ti ₃ AlC ₂ under the microwave irradiation. Gold nanocluster doped nanosheets sol (MXene@Au) with excellent stability and strong catalysis was synthesized with no product residue reducer CO. MXene@Au nanosol can catalyze mandelic acid-HAuCl ₄ to produce gold nanoparticles, which can be traced via resonance Rayleigh scattering (RRS) and surface-enhanced Raman scattering (SERS). Coupled the dual-mode nanocatalytic indicator reaction with aptamer reaction, a high sensitivity, selectivity, facile SERS/RRS dual-mode biosensnoring assay platform has been constructed for isocarbophos (ICP). The linear range of SERS was 1.0 × 10 ^-3 -2.5 × 10 ^-2  nmol/L, with a detection of limit 4.5 × 10 ^-5  nmol/L (S/N = 3). It has been used to detect ICP in water samples, with a good recovery (95.5-104%) and a good relative standard deviation (5.2-9.6%). This new nanocatalytic amplification biosensoring strategy can also assay other organic pesticides including malathion, glyphosate, profenofos and carbendazim. In addition, the nanocatalytic mechanism was investigated.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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