title: Measurement of free Cu ion activity in seawater using a passive-equilibrium sonic-assisted free ion recorder (SAFIR).
abstract: A passive equilibrium probe, sonic-assisted free ion recorder (SAFIR), was recently developed to monitor free Cu ion activity ({Cu(2+)}) in aquatic environments. The SAFIR is user-friendly and can be deployed on-site to record the ambient {Cu(2+)} in an accurate and fast manner. It consists of a chemically modified polystyrene disk (Primaria disk) containing metal ion-binding functional groups, coupled with a sonic horn in a flow-through cell. The calibration of the disk was successfully conducted in metal-ion buffered seawater solutions (pH 8.2, salinity = 32) with {Cu(2+)} ranging from 10(-9.0) to 10(-15.0) mol/L. The Cu adsorbed on the surface of the Primaria disk (Cu(ads)) correlated linearly with the ambient {Cu(2+)} through a Frendlich equilibrium adsorption model. The adsorption process was kinetically enhanced by the introduction of ultrasound, allowing equilibrium between the SAFIR and the ambient {Cu(2+)} in 10 min. The SAFIR was deployed in several coastal regions, and the {Cu(2+)} recorded by SAFIR were in good agreement with the results obtained from corresponding electrochemical analysis.
authors.affiliation: Department of Environmental, Earth and Ocean Science, University of Massachusetts Boston, 100 Morrissey Boulevard, Boston, Massachusetts 02125, United States.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Franco
authors.initials: F
authors.lastname: Pala
authors.forename: Jaclyn
authors.initials: J
authors.lastname: Haskins
authors.forename: Katrina
authors.initials: K
authors.lastname: Sukola
authors.forename: Gordon T
authors.initials: GT
authors.lastname: Wallace
mesh_terms: D003300:Copper / Q000032:analysis*; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D008404:Massachusetts; D012623:Seawater / Q000032:analysis*; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D014873:Water Pollutants; D003300:Copper