Sampling of dissolved inorganic Sb^III by mercapto-functionalized silica-based diffusive gradients in thin-film technique

Abstract

The mercapto-functionalized silica (MPS) diffusive gradients in thin-film (DGT) devices, for the first time, were characterized by the determination of dissolved inorganic SbIII.

In situ speciation of dissolved inorganic antimony in surface waters and sediment porewaters: development of a thiol-based diffusive gradients in thin films technique for SbIII

“…19 The diffusion coefficient of Sb III reported by Fan et al 18 is only 32% of the value determined in this study. This discrepancy is unlikely to be due to the difference in binding layer materials, as suggested by Fan et al, 18 because the polyethersulfone membrane used in their study has been used as a component of DGT diffusive layers previously without retarding diffusion to such a large extent. 24 To ensure accurate results, we recommend that laboratories independently determine diffusion coefficients with their specific DGT configuration.…”

“…The comparatively high elution efficiency obtained with 1 mol L -1 H2O2 / 1 mol L -1 NaOH may be due to the complete oxidation of the thiol functional groups on the mercapto-silica under these conditions. These elution procedures are much simpler than that reported by Fan et al 18 for the same binding gel, which required microwave-assisted extraction in concentrated HNO3, HCl, and HF. Subsequent elution of Sb III from DGT binding layers in this study was done with 1 mol L -1 H2O2 / 1 mol L -1 NaOH, except where otherwise stated.…”

“…17 Additionally, the application of selective binding agents that only accumulate a specific analyte oxidation state, have expanded the DGT technique to allow the in situ measurement of chemical speciation. Recently, Fan et al 18 described the application of a 3mercaptopropyl functionalised silica-based DGT technique for measuring Sb III in wastewater and freshwater, although this method was not tested in seawater and required a complicated elution procedure. Panther et al 13 described a Metsorb DGT technique for measuring Sb V in natural waters, although the ability of this technique to measure Sb III was not tested.…”

Molecularly imprinted polymer based diffusive gradients in thin‐films for in situ selective sampling and determination of ciprofloxacin

“…, the U % value of DGT sampler should be in the range of 90–110% . The uptake of CF by CMIP‐DGT in the synthetic solution containing 0.5 μg/mL increased linearly with time up to 120 h ( r 2 = 0.998, U % = 96.8%) and fitted the theoretical line which calculated from the known solution concentrations (Figure ) . These results indicated that the configuration of CMIP‐DGT was close to the ideal as described by the DGT equation and CMIP meet the requirements of DGT binding agent for the measurement of CF.…”

In-situ sampling of available calcium using diffusive gradients in thin-films technique based on benzo-crown ether-functionalised silica as the binding agent

“…A diffusion gradients in thin-films (DGT) technique has been proposed by Davison and Zhang (Davison and Zhang 1994;Turner et al 2014) as an in-situ, simple and long-term sampling tool for the assessment of labile metals speciation. The DGT technique is based on the selective diffusion across a diffusion layer (such as polyacrylamide hydrogel (Davison and Zhang 1994), cellulose acetate dialysis membrane (Li et al 2003), cellulose membrane (de Oliveira et al 2012), chromatography paper (Larner and Seen 2005), agarose gel (Dong et al 2014), nylon membrane (Wang et al 2016) and polyethersulfone (PES) membrane (Fan et al 2016)) and dissociation of metal species in a binding layer comprising binding agents (such as Saccharomyces cerevisiae (Pescim et al 2012), amberlite IRP-69 ion-exchange resin (Zhang et al 2014), amorphous zirconium oxide (Ding et al 2010), titanium dioxide (Bennett et al 2010), copper ferrocyanide (Li et al 2009), precipitated ferrihydrite (Luo et al 2010), XAD18 resin (Chen et al 2013) and molecularly imprinted polymer (Dong et al 2014)). Dahlqvist et al (2002) were the first to use the DGT technique, with a Bio-Rad ChelexÒ100 resin as the binding agent, for Ca 2þ and Mg 2þ measurements in freshwater.…”