Conversion of an invasive plant into a new solid phase for lead preconcentration for analytical purpose

Abstract

Abstract Eichornia crassipes is an atypical plant in the various regions of the Caribbean’s Central America e South American Countries. This plant causes severe problems in the aquatic environment of these places. Thus, it is necessary to remove this plant from the aquatic ecosystem causing immense environmental benefit. One alternative is transforming this plant into a solid low-cost phase for analytical methodologies and enabling cost reduction in the analysis of environmental pollutants. Toxic metal elements like lead have not function in the human body. It is crucial to determine lows concentrations of metals in water, foods, and beverages to assess daily consumption permissibility. Flame atomic absorption spectrometry (FAAS), compared to more sensitive equipment, is low-cost, easy-to-operate equipment, above all high precision and specificity. Their lack of sensitivity can be overcome with a preconcentration methodology. This work aims to transform the leaves of Eichornia crassipes into a new green solid-phase and find the best extraction conditions for Pb (II) determination by solid phase extraction (SPE) online with FAAS. The leaves of the plant were collected, washed with water, dried at room temperature, oven, milled, and sifted. The solid-phase extraction parameters, such as pH, type of eluent, sample flow rate, amount of sorbent, and eluent flow rate, were optimized. An experimental factorial design 24 was applied with the sample flow, eluent flow, column mass, and volume of complexing agent. The two-dimensional central and rotating composite design was applied to the variables that obtained significance through experimental design. The elimination of a complexing agent allowed the methodology to become more compatible with the principles of green chemistry. The enrichment factor and the limit of detection were 48.5 and 2.35 μ g L−1, respectively. The method was validated with SRM 1515 certified reference material. The SPE-FAAS online methodology with a minicolumn of Eichhornia crassipes is a simple, fast, economical, safe, and eco-friendly alternative for the determination of Pb(II).