Hyphenated\nCentrifugal Microsolid Phase Extraction\nand Centrifugal Acceleration Thin-Layer Chromatography in a Single\nDevice: An Innovative Approach to Perform Consecutive Extraction and\nSeparation

An innovative approach for extracting and separating\nanalytes consecutively\nfrom complex matrixes was introduced for the first time. The approach\ninvolves applying centrifugal force to a novel circular chip to expedite\nthe process of microsolid phase extraction and centrifugal acceleration\nthin-layer chromatography, followed by red–green–blue\n(RGB) analysis as a simple, fast, and in situ detection method. Furthermore,\nthe natural product of rice husk was utilized to create a sorbent\nwith great adsorption capabilities. In this method, curcumin and phenazopyridine\nwere employed as model drugs. The one-variable-at-a-time (OVAT) method\nwas used to study the factors that affect the extraction and separation.\nUnder the optimized conditions, a good relationship was observed between\nthe |<i>R</i>| + |<i>B</i>| intensity and the\nconcentration of analytes within the range of 1.0–10.0 μg/mL\n(<i>R</i><sup>2</sup> = 0.9903) for curcumin and 0.1–7.5\nμg/mL (<i>R</i><sup>2</sup> = 0.9933) for phenazopyridine\nin urine samples. Intra- and interday RSDs% (<i>n</i> =\n3) were obtained at less than 5.6 and 7.1%, respectively. In urine\nsamples, the limit of detection values was 0.75 μg/mL for curcumin\nand 0.05 μg/mL for phenazopyridine, and relative recovery values\nwere in the acceptable range of 85.0–100.2%. The suggested\napproach has the appropriate sensitivity, good accuracy, and acceptable\napplicability to determine curcumin and phenazopyridine in complicated\nmatrices.