A Non-Instrumental Green Analytical Method Based on Surfactant-Assisted Dispersive Liquid–Liquid Microextraction–Thin-Layer Chromatography–Smartphone-Based Digital Image Colorimetry(SA-DLLME-TLC-SDIC) for Determining Favipiravir in Biological Samples

Abstract

Favipiravir (FAV) has become a promising antiviral agent for the treatment of COVID-19. Herein, a green, fast, high-sample-throughput, non-instrumental, and affordable analytical method is proposed based on surfactant-assisted dispersive liquid–liquid microextraction (SA-DLLME) combined with thin-layer chromatography–digital image colourimetry (TLC-DIC) for determining favipiravir in biological and pharmaceutical samples. Triton X-100 and dichloromethane (DCM) were used as the disperser and extraction solvents, respectively. The extract obtained after DLLME procedure was spotted on a TLC plate and allowed to develop with a mobile phase of chloroform:methanol (8:2, v/v). The developed plate was photographed using a smartphone under UV irradiation at 254 nm. The quantification of FAV was performed by analysing the digital images’ spots with open-source ImageJ software. Multivariate optimisation using Plackett–Burman design (PBD) and central composite design (CCD) was performed for the screening and optimisation of significant factors. Under the optimised conditions, the method was found to be linear, ranging from 5 to 100 µg/spot, with a correlation coefficient (R2) ranging from 0.991 to 0.994. The limit of detection (LOD) and limit of quantification (LOQ) were in the ranges of 1.2–1.5 µg/spot and 3.96–4.29 µg/spot, respectively. The developed approach was successfully applied for the determination of FAV in biological (i.e., human urine and plasma) and pharmaceutical samples. The results obtained using the proposed methodology were compared to those obtained using HPLC-UV analysis and found to be in close agreement with one another. Additionally, the green character of the developed method with previously reported protocols was evaluated using the ComplexGAPI, AGREE, and Eco-Scale greenness assessment tools. The proposed method is green in nature and does not require any sophisticated high-end analytical instruments, and it can therefore be routinely applied for the analysis of FAV in various resource-limited laboratories during the COVID-19 pandemic.

Fabric phase sorptive extraction-gas chromatography-mass spectrometry for the determination of favipiravir in biological and forensic samples

“…The optimum value for pH is found to be 4.9 which can also be explained by the pKa value of FAV i.e., 5.1, which shows that it behaves as a weak acid in aqueous solution. The results obtained herein are in close agreement to previous reports for FAV in similar samples [37] . The optimum values for other factors are: 15 min (elution time), 711.97 rpm (agitation speed), and 20.38 % (ionic strength).…”

“…The ComplexGAPI index was utilised to assess the green character of the proposed method. It was chosen since it enables for the evaluation of the analytical technique in view of its environmental affability [ 37 , [44] , [45] , [46] , [47] , [48] ]. Herein, each arm of the hexagon in the GAPI pictogram corresponds to a distinct part of the process that is being described.…”

Recent overview of microextraction of metal ions and pharmaceuticals by solidified floating organic drop microextraction techniques

“…Recently VA-DLLME-thin-layer chromatography (TLC)image analysis method described by Jain et al for APAP in postmortem biological samples has been developed and validated. The proposed method is novel, it combines Human plasma HPLC/UV 0.5-50 0.15 0.45 [143] Human urine SW-AdSV 1.0-100.0 0.26 0.87 [144] Human plasma and urine TLLC-DIC 5-100 1.2-1.5 3.96-4.29 [145] VA-DLLME with a widely used and simple chromatographic technique. The method does not require any bulky high-end instrumental technique such as GC-MS or HPLC for quantitative analysis, which can be performed with a simple smartphone camera and free image processing software.…”

Simultaneous estimation of andrographolide, apigenin, apocynin, and gallic acid by high‐performance thin layer chromatography method with Greenness quality by design approach

“…It is the principal component of Boerhavvia diffusa [8]. The high-performance thin-layer chromatography (HPTLC) method is a suitable method for the estimation of chemical constituents present in plant materials [9][10][11][12][13][14][15][16][17]. Methods are validated according to International Council on Harmonization (ICH) guidelines and can be adopted for the routine analysis of ANDRO, APO, API, and GA in Hepatoprotective polyherbal formulation [18].…”