Optical detection/collection of toxic Cd(II) ions using cubic Ia3d aluminosilica mesocage sensors.

PMID 22939130


Optical sensors for selective removal and detection of extremely toxic ions such as cadmium (Cd(II)) in aquatic samples were successfully fabricated via simple strategy. Aluminosilica-based network platforms are used as selective mesopore shape and size carriers in order to fabricate optical sensors through the direct functionalization of α, β, γ, and δ-tetrakis(1-methylpyridinium-4-yl)porphine ρ-toluenesulfonate (TMPyP) moieties without any prior surface modification using silane or thiol agents. In turn, the key advantage of a heretical three-dimensional (3D) cubic Ia3d mesocage is the facile access of target ions such as ion transports and the high affinity responses of TMPyP receptor-Cd(II) analyte binding events, which result in the easy generation and transduction of optical signals even at the trace level of the Cd(II) ion. The optical sensor design-based aluminosilica cages enable the sensitive detection and selective removal of Cd(II) ions even at ultra-trace concentrations of 10(-10)mol/dm(3) with rapid response time (in minutes). This rational strategy is crucial to the development of optical mesocollectors (i.e., probe surface-mounted naked-eye ion-sensor strips) with highly selective Cd(II) ion removal from aqueous water. These new classes of optical mesocollectors exhibit long-term stability and reusability of deleterious Cd(II) ions, which makes them efficient for various analytical applications.