A new route to select the referable values of property indicators for normalization and its application in screening polymeric membrane heavy metal (Co, Ni, and Cr)-ion-selective electrodes with multiple high-response performances.

Distance to target normalization may not be suitable to select the referable values, (RC)refer, and responsive characteristic (RC) indicators, for the electrode comprehensive quality index (IECQ). (RC)refer is selected as an excellent response property value in alliance with corresponding constants (e.g., 1.8 or 2.5) in this method. It is recently found that these constants are not appropriate to normalize indicators for other ion-selective electrodes (ISEs). The present study aimed to report a new and universal route to select good (RC)refer values for the normalization without additional constants by only controlling the mean value ([Formula: see text]) being 0.90 < [Formula: see text] < 1.1. The route provided reliable results of both (RC)refer for indicator normalization and IECQ values. It has been successfully applied to select the referable values (RC)refer of each indicator for the IECQ of three heavy metal (HM) (Co, Ni, and Cr)-ISEs. The second aim of the work is to screen these heavy metal-ion-selective electrodes (HM-ISEs) with highly multiple response properties by using the IECQ. Twenty-four HM-ISEs with the top 3 IECQ values have been recommended. For example, the largest IECQ for three indicators, [Formula: see text], PS, and PRT, which was used as the main indicator (MI), was 1.461 for Co2+-ISE, 1.385 for Ni2+-ISE, and 1.561 for Cr3+-ISE, respectively. The results will be beneficial to meeting the special requirements to monitor/analyze HM ions in different water samples.

An integrated measurement of six response performance indicators for lead ion-selective electrodes and application.

A heavy metal ion-selective electrode (ISE) with highly multiple response performances, rather than a high single response performance, is needed urgently for in situ, real-time environmental monitoring. In this study, we present an integrated measurement of six response performance variables such as the response slope, selectivity, dynamical range, detection limit, response time, and lifetime. They are selected and used as the indicators of the quality assessment for Pb2+-ISEs. The measurement, named as electrode comprehensive quality index (IECQ), is a single number for a given ISE. The comprehensive qualities of 114 Pb2+-ISEs reported in the literature were evaluated through the index method. Twenty-one Pb2+-ISEs-based polymer membrane with top 3 IECQ values for seven different properties have been recommended by evaluating and screening of the electrodes. Five Pb2+-ISEs-based polymer membrane with the best single response performance were also provided. The recommended Pb2+-ISEs, along with the corresponding Pb2+-ISEs with the miniaturized configurations, will provide helpful guideline for the application of Pb2+-ISE with highly multiple response performances in real-time environmental monitoring.