Development of an electroanalytical method using activated rice husk-derived carbon for the detection of a paraquat herbicide

Smartphone-Based Paper Microfluidic Detection of Paraquat Mediated by Citrate-Capped Silver Nanoparticles

“…Colorations were quanti ed using red-toblue (R/B) intensity ratios and red-to-green (R/G) intensity ratios. As previously reported, red intensity changes the most upon AgNP aggregation [9], and blue and green intensities serve as references to address the biases in paper color and ambient lighting. These data (normalized red intensities, I) were then converted to absorbance (A) values using A = log (I 0 / I) [27], where I 0 is the intensity of blank…”

“…Many analytical methods have been developed for evaluating paraquat levels in ecosystems. Such analyses include ow injection analysis [4], liquid chromatography-mass spectrometry (LC-MS) [7], highperformance liquid chromatography (HPLC) [8], electrochemical analysis [9], and uorescence-probe detecting analysis [10]. These methods have generally provided excellent LOD and selectivity for paraquat detection.…”

Strategy for optimizing the synthesis and characterization of activated carbons obtained by chemical activation of coffee husk

“…30 This last plan is increasingly used because it can make it possible to start a study with a minimum of experiments and to adjust if the model is not validated without however losing the results of the previous tests. 27 The central composite design is used to optimize the main influencing parameters in the preparation of activated carbons. The independent variables chosen according to the screening plan are, among others, the concentration of the activating agents, the residence time in the furnace and the carbonization temperature.…”

“…The increase in iodine number with decreasing temperature can be explained by infering that decreasing temperature can cause opening of pores and consequently increasing the adsorption of iodine molecules. 27,40 Thus, as the temperature decreases for the phosphoric acid activation, the decrease in iodine value could be associated with dehydration and destruction of micropores at long residence times in the oven. 41 It turns out that the concentration of the activating agent, the residence time in the furnace and the calcination temperature improve the performance of the activated carbon.…”

“…27 The response surface methodology appears today as the best optimization tool that studies the synergistic and antagonistic effect between several parameters on the responses with a limited number of experiments. 27,28…”