Semiquantitative analysis mode in inductively coupled plasma mass spectrometry (ICP-MS) has been popularly used for fast screening purposes. Although the benefit of it has been studied by many researchers, its performance of application in real-world routine analyses has not been reported.
In this study, we evaluated the reliability of semiquantitative analysis mode through inter-laboratory comparison using two different ICP-MS systems with one multi-element calibration standard. The suitability of semiquantitative analysis mode in routine analysis laboratory was demonstrated by evaluating its application in different laboratories and in real production laboratory practices. Twenty one elements were measured, namely, Be, B, Al, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Sr, Mo, Ag, Cd, Sn, Sb, Ba, Tl, and Pb in various fresh water reference samples. Good results concerning accuracy (relative percentage error within 10%) and reproducibility (relative standard deviation lower than 5%) were obtained in more than 90% analyzed samples at concentrations equal to or greater than 10 times the detection limit (DL). Semiquantitative analysis mode also enabled the determination of elements that are not present in the calibration standard. The results demonstrated the potential of semiquantitative analysis mode as a reliable approach in routine laboratory determination of simple matrices, where high throughput and cost-effectiveness are desired, as well as in emergency situations where speed of analysis is critical and quite often limited sample information is available. 相似文献
It is critical to develop a cost-effective quantitative/semiquantitative assay for rapid diagnosis and on-site detection of toxic or harmful substances. Here, a naked-eye based semiquantitative immunochromatographic strip (NSI-strip) was developed, on which three test lines (TLs, TL-I, TL-II and TL-III) were dispensed on a nitrocellulose membrane to form the test zone. Similar as the traditional strip assay for small molecule, the NSI-strip assay was also based on the competitive theory, difference was that the analyte competed three times with the capture reagent for the limited number of antibody binding sites. After the assay, the number of TLs developed in the test zone was inversely proportional to the analyte concentration, thus analyte content levels could be determined by observing the appeared number of TLs. Taking aflatoxin B1 as the model analyte, visual detection limit of the NSI-strip was 0.06 ng mL−1 and threshold concentrations for TL-I–III were 0.125, 0.5, and 2.0 ng mL−1, respectively. Therefore, according to the appeared number of TLs, the following concentration ranges would be detectable by visual examination: 0–0.06 ng mL−1 (negative samples), and 0.06–0.125 ng mL−1, 0.125–0.5 ng mL−1, 0.5–2.0 ng mL−1 and >2.0 ng mL−1 (positive samples). That was to say, compared to traditional strips the NSI-strip could offer more parameter information of the target analyte content. In this way, the NSI-strip improved the qualitative presence/absence detection of traditional strips by measuring the content (range) of target analytes semiquantitatively. 相似文献
Room temperature acid sonication of milk samples is proposed as a fast alternative methodology for the determination of the total content of 45 elements (Li, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Y, Mo, Ag, Cd, In, Sn, U, Sb, Te, Cs, Ba, Hg, Pb, Bi, Th, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Hf and Ta) in milk by inductively coupled plasma mass spectrometry (ICP-MS). The aforementioned procedure involves a 10 min sample pre-treatment. Measurements were made in quantitative and semiquantitative (Totalquant®) modes of analysis using Rh as internal standard and Be, Ge, Tb and Re for internal calibration of the equipment in the semiquantitative mode. The selected isotopes were in general the most abundant ones of each element, except in cases where polyatomic or isobaric interferences were detected. Results of total concentrations in 10 liquid and 11 powdered commercially available milk samples were presented. Method validation was performed by measuring a SRM NIST-1549 non-fat milk powder and through the use of recovery experiments. Additionally, the proposed methodology was compared with a method based on a previous microwave-assisted digestion of samples and a direct analysis of 1:4 diluted samples. 相似文献