Vortex-assisted switchable liquid-liquid microextraction for the preconcentration of cadmium in environmental samples prior to its determination with flame atomic absorption spectrometry

Abstract

In this study, a switchable solvent was used to preconcentrate trace amounts of Cd from aqueous solution for its determination by flame atomic absorption spectrometry (FAAS). Protonation of N,N-dimethylbenzylamine by dry ice (solid CO) made it water soluble, and addition of sodium hydroxide converted it back to its original nonionic state for phase separation and subsequent extraction of Cd. A slotted quartz tube (SQT) was attached to the flame burner head to increase the residence time of Cd atoms in the light path. Under the optimum conditions, limits of detection and quantification were determined as 0.7 and 2.6 μg L, respectively. Low relative standard deviations calculated from seven replicate measurements of the lowest concentration indicated high precision. Accuracy of the developed method was checked by using a standard reference material (SRM 1633c). Spiked recovery tests were also performed on lake water and wastewater samples at different concentrations to check the applicability of the developed method, and the results obtained (90-103%) established high recovery.

A comprehensive review on recent developments and future perspectives of switchable solvents and their applications in sample preparation techniques

“…133 SSs were created by Arain et al 134 using the same amount of DBU-decanol and CO 2 for 3–7 minutes while being stirred continuously at 200–600 rpm by a magnetic stirring bar. N , N -dimethylbenzylamine was combined with water by Firat et al , 135 resulting in the initial observation of two distinct phases. The two-phase system formed a cloudy upper phase solution when 18–20 g of dry ice was intermittently added while the mixture was being constantly stirred.…”

“…The discovered approach, when applied to well and lake water samples spiked at various doses, produced recovery rates ranging from 92 to 107%. 164 Triethylamine and water were combined as the switchable-hydrophilicity solvent. The ratio of the ionized and non-ionized forms of triethylamine could therefore be used to manage the ideal circumstances because the pH was controlled by carbon dioxide.…”

“…5. [122][123][124]126,127,[142][143][144][145][146][147][148][149][150][151] 5.9. Effect of pH on SSs pH plays a vital role in the extraction capability of extraction methods using SSs, and is considered to be one of the most important factors to be optimized, because the switching behavior of the SS from hydrophobic to hydrophilic plays a prominent role in the extraction of target analytes from aqueous medium to the extraction solvents (SSs).…”

Zinc Oxide Nanomaterial‐Based Dispersive Solid Phase Extraction for the Trace Determination of Gold in Flash Gold Plating Solution Samples using Flame Atomic Absorption Spectrophotometry

“…Simultaneous determination of multiple elements at trace concentrations can be done by using highly sensitive analytical instruments such as instrumental neutron activation analysis (INAA), [12] inductively coupled plasma‐optical emission spectrometry (ICP‐OES) [13] and inductively coupled plasma mass spectrometry (ICP‐MS) [14] . However, these instruments are more expensive than the basic FAAS system and the level of expertise required to run these sophisticated instrument is quite high [15] . An alternative approach to buy expensive instruments to overcome the low sensitivity of FAAS is to use microextraction methods that are capable of separating analytes of interest from the matrix of samples and concentrate them into the amounts that are easily detected and quantified [15] .…”

“…[14] However, these instruments are more expensive than the basic FAAS system and the level of expertise required to run these sophisticated instrument is quite high. [15] An alternative approach to buy expensive instruments to overcome the low sensitivity of FAAS is to use microextraction methods that are capable of separating analytes of interest from the matrix of samples and concentrate them into the amounts that are easily detected and quantified. [15] The past two decades have seen significant breakthroughs in the development of different microextraction methods for both organic and inorganic compounds.…”