Determination of nitenpyram and 6‐chloronicotinic acid in environmental samples by ion chromatography coupled with online photochemically induced fluorescence detector

Abstract

A simple, cost-effective, sensitive, and quick method for the determination of nitenpyram and its metabolite 6-chloronicotinic acid in environmental samples was developed by coupling an ion chromatograph with a fluorescence detector and a post-column photochemical reactor. This developed analytical method involved a rapid sample extraction by modified and miniaturized quick, easy, cheap, effective, rugged, and safe method followed by isocratic ion chromatographic separation of nitenpyram and 6-chloronicotinic acid into an IonPac AS11-HC column protected by IonPac AG11A guard column by running 30 mM NaOH + 10% acetonitrile mobile phase. A homemade post-column photochemical reactor was also integrated with the ion chromatographic system for online transformation of both analytes into their respective highly fluorescent photoproduct in basic media without using an extra pump. The developed method was validated by following SANTE/11945/2015 guidelines on analytical quality control and validation procedures. The method showed a good linear response (r > 0.999), improved limit of detection (0.101-0.132 μg/L), minimum or no matrix effect, excellent recoveries (90.2-100.10%) and relative standard deviations were found to be ≤6.50%.

Simultaneous determination of acetamiprid and 6‐chloronicotinic acid in environmental samples by using ion chromatography hyphenated to online photoinduced fluorescence detector

“…Besides, these are also causing direct or indirect adverse effects on consumers health, and risk for wild/honey bees is real [8,9]. Therefore, due to their mobility in plants and environmental matrices has compelled the analysts to amend the European Union legislation to set the maximum residue limits (MRLs) for most of the neonicotinoid insecticides in the range 0.1-1 mg/ kg in various matrices [9][10][11][12]. Acetamiprid (ATP) along with imidacloprid is mainly used insecticide all over the world [8].…”

“…Acetamiprid (ATP) along with imidacloprid is mainly used insecticide all over the world [8]. Both of these can easily transform into their main metabolite called 6-chloronicotinic acid (6-CNA) [12,13]. Both analytes (ATP & 6-CNA) chemical structures and basic physical properties are given in Table 1.…”

“…It was investigated that ATP and its metabolite ability to persist significantly and high solubility in the water system have posed a serious threat to human health and environmental safety even at trace levels [13,14]. Therefore, sensitive and selective determination of ATP and its metabolite at trace level is essential for the comprehensive assessment of environmental compartment contamination and human exposure to these neonicotinoids [12].…”

“…Whereas, conventional HPLC equipped with UV or DAD is a commonly used alternative technique because of its low cost and versatility [3,8,10,14]. But its successful application is impeded by poor selectivity and sensitivity of UV detector for the accurate quantification of neonicotinoids in the sample matrices [6,7,12,19,20]. LC coupled with a fluorescence detector (LC-FLD) is a comparatively simple, cost-effective, sensitive, and selective technique for the high-throughput and accurate quantification of analytes of interest [21].…”

Trace analysis of rimantadine in human urine after dispersive liquid liquid microextraction followed by liquid chromatography–post column derivatization

“…In liquid chromatography, the derivatization procedure can be performed either in pre-column or postcolumn mode; the latter offers interesting advantages, such as (i) it is in principle an automated flow-based step, (ii) the stability of the derivatives is not of concern, and (iii) it is more efficient when complicated matrixes are analyzed since each analyte is derivatized in "isolation" following the chromatographic separation. This way one of the critical disadvantages of the pre-column mode, that is potentially competition phenomena from the sample matrix, are avoided [26][27][28][29].…”