Application of flowerlike MgO for highly sensitive determination of lead via matrix‐assisted laser desorption/ionization mass spectrometry

Abstract

RATIONALE: Matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is a high-throughput method to achieve fast and accurate identification of lead (Pb) exposure, but is seldom used because of low ionization efficiency and insufficient sensitivity. Nanomaterials applied in MS are a promising technique to overcome the obstacles of MALDI. METHODS: Flowerlike MgO nanostructures are applied for highly sensitive lead profiling in real samples. They can be used in two ways: (a) MgO is mixed with N-naphthylethylenediamine dihydrochloride (NEDC) as a novel matrix MgO/NEDC; (b) MgO is applied as an absorbent to enrich Pb ions in very dilute solution. RESULTS: The signal intensities of lead by MgO/NEDC were ten times higher than the NEDC matrix. It also shows superior anti-interference ability when analyzing 10 μmol/L Pb ions in the presence of organic substances or interfering metal ions. By applying MgO as adsorbent, the LOD of lead before enrichment is 1 nmol/L. Blood lead test can be achieved using this enrichment process. Besides, MgO can play the role of internal standard to achieve quantitative analysis. CONCLUSIONS: Flowerlike MgO nanostructures were applied for highly sensitive lead profiling in real samples. The method is helpful to prevent Pb contamination in a wide range. Further, the combination of MgO with MALDI MS could inspire more nanomaterials being applied in highly sensitive profiling of pollutants.

Microscale flower-like magnesium oxide for highly efficient photocatalytic degradation of organic dyes in aqueous solution

“…6b and S8 (see the ESI †), aer ve cycles, a degradation efficiency as high as 92.2% could still be obtained. In the previous studies, 14,[64][65][66][67][68][69][70][71] although different shapes of micrometer-sized ower-like MgO have also been reported, few 66,68,69 are analogous to the shape of obtained MgO in the current study. Also, their performance had much difference.…”

Determination of copper and lead in tequila by conventional matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and partial least squares regression

“…For a quantitative approach in the analysis of small molecules by MALDI‐HRMS, normalization of the analytical signal by an appropriate internal standard is highly recommended . In this work, bismuth and indium were selected for this purpose with the intent to compensate for errors committed during sample preparation and during signal acquisition; indeed, both metal ions form complexes with diethyldithiocarbamates that can be extracted into chloroform at neutral pH, and none of them was detected by ICP‐MS while analyzing commercial tequilas.…”

“…Beyond any doubt, inductively coupled plasma mass spectrometry (ICP‐MS) is the first‐choice technique for the determination of trace metal/metalloids in any real‐world sample; however, there have also been several applications of conventional MALDI‐HRMS reported, offering a memory‐free, high‐throughput, high‐resolution, micro‐scale alternative with instrument operation costs much lower as compared with ICP‐MS. In this regard, we have recently demonstrated the feasibility of conventional MALDI coupled to time‐of‐flight mass spectrometry (TOFMS) for the determination of mercury and copper in fish tissues.…”

“…[6][7][8][9][10] In another approach for enhanced determination of small molecules, a considerable effort has been dedicated to the improvement of sample preparation and on the selection of instrumental conditions in conventional MALDI thus avoiding undesired matrix effects. [11][12][13] Beyond any doubt, inductively coupled plasma mass spectrometry (ICP-MS) is the first-choice technique for the determination of trace metal/metalloids in any real-world sample; however, there have also been several applications of conventional MALDI-HRMS reported, [14][15][16][17][18] offering a memory-free, high-throughput, highresolution, micro-scale alternative with instrument operation costs much lower as compared with ICP-MS. In this regard, we have recently demonstrated the feasibility of conventional MALDI coupled to time-of-flight mass spectrometry (TOFMS) for the determination of mercury and copper in fish tissues.…”