Development of a microplate-format direct optode sensor for ultra-high-throughput environmental and wastewater monitoring of Pb2.
Anal Chim Acta
; 1167: 338586, 2021 Jul 04.
Article
en En
| MEDLINE
| ID: mdl-34049633
ABSTRACT
Although many Pb2+-selective optodes have been developed so far, methods using optical sensor membranes have not become widespread in environmental analytical practice. In order to create a bulk optode sensor, which can overcome all of the main drawbacks in the application of conventional optode membranes, - i.e., pH-dependence, long response time and the leakage of the ionic components - unusually thick PVC membrane was developed, embedded in microtiter plates and operated on a novel concept. This is the first reported work, which applies a plate-format optode as well as a direct optode-type sensing membrane for determination of Pb2+. We reported here also the first example for the application of an ionic component-free bulk optode membrane to avoid the membrane leakage, improve the regenerability and extend the lifetime of the membrane. The reported sensor has a LOD above 4.0 × 10-7 M (â¼83 µg L-1), thus it is unsuitable for the effective monitoring of drinking waters, but considered to be a promising method for monitoring contamination episodes. On the other hand, the widest pH-independent working range of 4.3 < pH < 7.0 among bulk optodes reported in the literature was realized and an unprecedentedly fast response time of <10 s was achieved. The effectiveness of the applied method was investigated by measuring Pb2+-spiked multicomponent aqueous solutions as simulated environmental or wastewater samples containing near equimolar amounts of Ag+, Ca2+, Co2+, Cu2+, K+, Mg2+, Na+ and Zn2+ as acetate salts. In the presence of these potential competing ions with a concentration not greater than the typical ionic strength of surface freshwaters (â¼10-3 M) the reported sensor proved to be appropriate for the selective detection of Pb2+ without any preparation of the samples (e.g., preconcentration, buffering, addition of excipients, etc.) with a required sample volume of only 100 µL. An outstanding analytical performance could be achieved within an average time of less, than 5 s/sample. The reported fluorescent probe is considered to be a promising method for replacing atomic absorption spectroscopy- (AAS), anodic stripping voltammetry- (ASV) or inductively coupled plasma- (ICP) based techniques as well as conventional ion-selective bulk membranes in high-throughput preliminary environmental monitoring of Pb2+, as it provides a cheap and unprecedentedly fast qualitative analysis of contaminated surface and wastewaters.
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Colección:
01-internacional
Base de datos:
MEDLINE
Tipo de estudio:
Qualitative_research
Idioma:
En
Revista:
Anal Chim Acta
Año:
2021
Tipo del documento:
Article