Covalent binding of sensor phases--a recipe for stable potentials of solid-state ion-selective sensors.
In this work, a new concept of the solid-state sensors free from EMF instabilities is proposed. In order to prevent the formation of an aqueous layer underneath the ion-selective membrane, instead of improving the hydrophobicity of the monolayer, the moieties terminated with acrylate groups were incorporated within the redox-active monolayer structure. It allowed to "sew" all phases of the sensor (i.e., the transducer, the intermediate layer and the ion-selective membrane) and to obtain a stable and durable ion-selective sensor. It is shown that newly designed monolayer containing both the ferrocene- and the acrylate-terminated molecules does not affect the working parameters of the electrode, such as selectivity or the slope of the calibration curve, although the EMF drift of the sensor is significantly reduced to 0.2 mV per day.
Grygołowicz-Pawlak
Ewa
E
Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
Palys
Barbara
B
Biesiada
Krzysztof
K
Olszyna
Andrzej R
AR
Malinowska
Elzbieta
E
D000179:Acrylates / Q000737:chemistry*; D001665:Binding Sites; D002138:Calibration; D004563:Electrochemistry; D005296:Ferrous Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D017736:Ion-Selective Electrodes; D007477:Ions / Q000737:chemistry; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force / Q000295:instrumentation / Q000379:methods; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011199:Potentiometry / Q000295:instrumentation / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods; D013499:Surface Properties; D013997:Time Factors
D000179:Acrylates; D005296:Ferrous Compounds; D007477:Ions; D008567:Membranes, Artificial; D006046:Gold