Development of sensitive and selective food sensors using new Re(I)-Pt(II) bimetallic complexes to detect volatile biogenic sulfides formed by meat spoilage

Detection of volatile biogenic sulfides (VBS) plays a crucial role in food safety because the amounts of these compounds can reflect the freshness of meat. A new indicator-displacement assay with Re(I)-Pt(II) complexes, [Re(Lig)(CO)₃(bridge)]–[Pt(DMSO)(Cl)₂] (1: Lig= 5-phenyl-1,10-phenanthroline and bridge = NCS-; 2: Lig= 5-phenyl-1,10-phenanthroline and bridge = CN-; 3: Lig= 2,2′-biquinoline and bridge = NCS-), was demonstrated to be a very effective sensing method to VBS. The results indicated that the control of Re(I)–bridge–Pt(II) and Re(I)–ligand combination are able to regulate their sensing selectivity and sensitivity. This system was successfully applied to detect CH₃SCH₃ in real rotten pork with a linear luminometric response up to 20.0 mgkg⁻¹ (R = 0.997) with the detection limit as 0.05 mgkg⁻¹. Complex 1 also gave comparable results on the detection of VBS with respect to those determined by GCMS with recovery range from 76 to 102% (RSD% = 13.8). Copyright © 2016 Elsevier B.V.