Development of a novel fluorimetric bulk optode membrane based on meso-tetrakis(2-hydroxynaphthyl) porphyrin (MTHNP) for highly sensitive and selective monitoring of trace amounts of Hg2+ ions

Assessing glyphosate concentrations in six reservoirs of Paraíba do Sul and Guandu River Basins in southeast Brazil

“…Where s is the standard deviation of the blank sample and S is the slope of the regression line equation. The recovery was calculated according to Ribani et al (2004) using known values of glyphosate added in an exempted matrix. The recovery mean values were between 59% and 103%.…”

“…The precision of the value obtained in this study was 13.98%, and it was determined by the relative standard deviation (RSD). This parameter represents the dispersion of the results, and in case of experiments with trace elements, it is accepted a RSD of up to 20% (Ribani et al, 2004).…”

Simultaneous determination of ultra-low traces of lead and cadmium in food and environmental samples using dispersive solid-phase extraction (DSPE) combined with ultrasound-assisted emulsification microextraction based on the solidification of floating organic drop (UAEME-SFO) followed by GFAAS

“…The hair sample was prepared as reported. 22 Hair samples were collected from the vertex of the scalp by cutting from the scalp region, and the hair length varied between 3 and 5 cm prior to analysis, all hair samples were cut into 2 cm with a stainless steel scissor. The hair samples were then washed three times with doubly distilled deionized water, and oven-dried at 100 C. About 0.1000 g of the dried sample was placed in a 50 mL beaker and 5 mL concentrated HNO 3 (65%) and 1 mL concentrated HClO 4 (70-72%) were added.…”

Luminescent chemosensor for Hg2+ ion based on a dinuclear Ru(II) complex containing open chain azacrown ether

“…One sensor reported by Xu et al was designed based on a Hg 2+ -promoted deprotection reaction of the dithioacetal by transforming a weakly fluorescent precursor (colorless) to a highly fluorescent aldehyde product [20]. Although a variety of organic molecules and polymers were used as luminescent indicators for Hg 2+ sensing with different mechanisms, some of them usually suffer from the water-fast, complicated synthesis, small Stokes' shifts, limited photostability, and necessary hydrolysis [21][22][23].…”