Fast and Direct Na and K Determination in Table, Marine, and Low-Sodium Salts by X-ray Fluorescence and Chemometrics

Abstract

X-ray fluorescence (XRF) is a fast, low-cost, nondestructive, and truly multielement analytical technique. The objectives of this study are to quantify the amount of Na(+) and K(+) in samples of table salt (refined, marine, and light) and to compare three different methodologies of quantification using XRF. A fundamental parameter method revealed difficulties in quantifying accurately lighter elements (Z < 22). A univariate methodology based on peak area calibration is an attractive alternative, even though additional steps of data manipulation might consume some time. Quantifications were performed with good correlations for both Na (r = 0.974) and K (r = 0.992). A partial least-squares (PLS) regression method with five latent variables was very fast. Na(+) quantifications provided calibration errors lower than 16% and a correlation of 0.995. Of great concern was the observation of high Na(+) levels in low-sodium salts. The presented application may be performed in a fast and multielement fashion, in accordance with Green Chemistry specifications.

Cancer Salt Nostalgia

“…All these methods report data from wet tissue or dry tissue measurement with varying levels of repeatability and reproducibility. However, all these methods require a significantly large tissue sample, of either approximately 0.5 cm in diameter or a tumor tissue volume of around 50–70 μL [ 79 , 80 , 81 , 82 , 83 ]. Further, these techniques cannot differentiate between extracellular versus intracellular sodium concentrations.…”

An overview of the Brazilian contributions to Green Analytical Chemistry

“…Additionally, different strategies for multivariate calibration in accordance with GAC have been proposed. For instance, X-ray fluorescence (Da-Col et al 2015) was used to quantify directly Na and K in table, marine and low-sodium salts using the entire spectra instead of peak values as in the univariate approach.…”

XRF analysis searching for fingerprint elemental profile in south-eastern Sicily tomatoes

“…As a matter of fact, the incident X-ray beam is mainly scattered and poorly absorbed by organic samples particularly rich in light elements, such as C, H, O and N. In this case, a more extensive knowledge of chemical composition of a sample could be achieved by working in other spectral regions and using scattering-based spectrometric techniques, such as Rayleigh, Compton and Raman ones. 5 , 6 .…”