TY - JOUR

T1 - An organic/inorganic LAPS array

T2 - Microfabrication, silanization, potentiometric characterization and ultra-low detection of heavy metals

AU - Ha, D.

AU - Wang, X.

AU - Wan, H.

AU - Su, K.

AU - Kirsanov, D.

AU - Wang, P.

PY - 2014/6/1

Y1 - 2014/6/1

N2 - A sensor array comprising light-addressable potentiometric sensors with solvent polymeric and chalcogenide glass membrane was developed and applied for the detection of lead and cadmium ions' activity. The course of silanization of sensor surface before organic/inorganicmembrane preparation had reduced the surface sensitivity to H+ (from 57.299 mV/pH decreased to 4.9996 mV/pH). The integrated hybrid LAPS array based on these membranes had showed a Nernstian response of slope (28-30 mV/dec) over the concentration ranges of 10-5-10-1 mol/L for cadmium(II) and lead(II) with a fast, stable and reproducible response. Potentiometric characterization was evaluated in terms of sensitivity, selectivity, stability, detection limit, linear response range and response time, thereby being compared between organic-membrane based LAPS and inorganic one. Moreover, ultra-low concentration calibration of the sensor based on chalcogenide glass membrane was undertaken in buffered saline media in order to assess the suitability for seawater analyses. The sensor slopes in saline citrate were 29.7 mV/dec and 29.3 mV/dec for cadmium(II) and lead(II) respectively, within concentrations ranging from 10-6 M to less than 10-18 M. The calibration lines in the citrate-buffer were essentially collinear with the response in unbuffered nitrate standards containing >10-5 M detected ions.

AB - A sensor array comprising light-addressable potentiometric sensors with solvent polymeric and chalcogenide glass membrane was developed and applied for the detection of lead and cadmium ions' activity. The course of silanization of sensor surface before organic/inorganicmembrane preparation had reduced the surface sensitivity to H+ (from 57.299 mV/pH decreased to 4.9996 mV/pH). The integrated hybrid LAPS array based on these membranes had showed a Nernstian response of slope (28-30 mV/dec) over the concentration ranges of 10-5-10-1 mol/L for cadmium(II) and lead(II) with a fast, stable and reproducible response. Potentiometric characterization was evaluated in terms of sensitivity, selectivity, stability, detection limit, linear response range and response time, thereby being compared between organic-membrane based LAPS and inorganic one. Moreover, ultra-low concentration calibration of the sensor based on chalcogenide glass membrane was undertaken in buffered saline media in order to assess the suitability for seawater analyses. The sensor slopes in saline citrate were 29.7 mV/dec and 29.3 mV/dec for cadmium(II) and lead(II) respectively, within concentrations ranging from 10-6 M to less than 10-18 M. The calibration lines in the citrate-buffer were essentially collinear with the response in unbuffered nitrate standards containing >10-5 M detected ions.

KW - Heavy metals

KW - Light-addressable potentiometric sensor (LAPS) array

KW - Organic/inorganic hybrid sensor

KW - Silanization

KW - Ultra-low concentration

UR - http://www.scopus.com/inward/record.url?scp=84911365570&partnerID=8YFLogxK

U2 - 10.1166/sl.2014.3205

DO - 10.1166/sl.2014.3205

M3 - Article

AN - SCOPUS:84911365570

VL - 12

SP - 978

EP - 984

JO - Sensor Letters

JF - Sensor Letters

SN - 1546-198X

IS - 6-7

ER -