Publications by authors named "Vahid Hamedpour"

We report a paper-based chemosensor array device (PCSAD) for the quantitative detection of oxyanions including the herbicide glyphosate (GlyP) in aqueous media. The mechanism of the oxyanion detection relies on a coordination-binding-based sensor array. In this study, the competitive coordination binding among Zn , four catechol dyes, and seven oxyanions caused noticeable colour changes.

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Simple, rapid, and accurate detection methods for saccharides are potentially applicable to various fields such as clinical and food chemistry. However, the practical applications of on-site analytical methods are still limited. To this end, herein, we propose a 96-well microtiter plate made of paper as a paper-based chemosensor array device (PCSAD) for the simultaneous classification of 12 saccharides and the quantification of fructose and glucose among 12 saccharides.

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Although microfluidic paper-based analytical devices (μPADs) get a lot of attention in the scientific literature, they rarely reach the level of commercialization. One possible reason for this is a lack of application of machine learning techniques supporting the design, optimization and fabrication of such devices. This work demonstrates the potential of two chemometric techniques including design of experiments (DoE) and digital image processing to support the production of μPADs.

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We believe that "the simpler we are, the more complete we become" is a key concept of chemical sensing systems. In this work, a "turn-on" fluorescence chemosensor array relying on only two self-assembled molecular chemosensors with ability of both qualitative and quantitative detection of phosphorylated saccharides has been developed. The easy-to-prepare chemosensor array was fabricated by in situ mixing of off-the-shelf reagents (esculetin, 4-methylesculetin, and 3-nitrophenylboronic acid).

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Although the determination of oxyanions due to correlation with metabolic processes and diseases is in high demand, most of the developed methods are suffering from a shortage of a capability of on-site analysis, sensitivity, and user-friendliness. This paper introduces the first colorimetric chemosensor array targeting various anions including glyphosate. The proposed sensor benefits from some notable features such as utilizing only commercially available reagents, recognizing similarly structured compounds by biomaterial-free sensors, and providing a fingerprint-like response originating from pattern recognition.

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In this work, an application of a design of experiments approach for the optimization of an isoniazid assay on a single-area inkjet-printed paper-based analytical device (PAD) is described. For this purpose, a central composite design was used for evaluation of the effect of device geometry and amount of assay reagents on the efficiency of the proposed device. The factors of interest were printed length, width, and sampling volume as factors related to device geometry, and amounts of the assay reagents polyvinyl alcohol (PVA), NH4OH, and AgNO3.

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This manuscript reports on the application of chemometric methods for the development of an optimized microfluidic paper-based analytical device (μPAD). As an example, we applied chemometric methods for both device optimization and data processing of results of a colorimetric uric acid assay. Box-Behnken designs (BBD) were utilized for the optimization of the device geometry and the amount of thermal inkjet-deposited assay reagents, which affect the assay performance.

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