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Influence of the nitric acid concentration on the signals generated by solutions of Re (50 g/kg), Co, Tl, La, Cs, Pb and Sr (20 g/kg)
Source publication
Two microwave digestion systems (open-focused and closed-pressurized) were tested for the mineralization of human brain and bovine liver (NIST SRM 1577a) as dissolution steps prior to the determination of 16 trace elements (Bi, Cd, Co, Cs, Cu, Fe, Hg, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn) by inductively coupled plasma mass spectrometry (ICP-MS)....
Citations
... Most subsequent studies have adopted mixtures of acids (nitric acid:perchloric acid (HNO 3 :HClO 4 ) = 7:1) for digestion (Ardestani et al., 2013), and nitric acid alone has been used in several studies (Bur et al., 2010(Bur et al., , 2012. Nitric acid/hydrogen peroxide (HNO 3 /H 2 O 2 ) has also usually been adopted for wet digestion of biological samples (Krachler et al., 1996;Kazi et al., 2009;Pengping and Kungwankunakorn, 2014). Furthermore, conditions such as digestion temperature, digestion time, quantity of digestion reagents and sample weight often differed greatly in previous studies using the method, and this has greatly influenced the digestion procedure (Zhou et al., 1995;van Gestel and Mol, 2003;Davis et al., 2006;Bur et al., 2010). ...
Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural soils. The present study sought to develop a method for cadmium (Cd) determination in soil micro-arthropods by optimizing the sample digestion procedure, reducing sample weight, modifying sample pre-treatment and validating the methodology with field samples. The optimized digestion conditions comprised a sample mass of 50–150 µg, digestion reagent of nitric acid:hydrogen peroxide (3:1), digestion temperature of 105 °C, digestion period of 3 h and digestion volume of 30 µL. Defecation of the standard Collembola Folsomia candida (92 h) and the indigenous Collembola Onychiurus yodai (42 h) and ultrasonic cleaning of F. candida increased the accuracy of Cd determination. The recovery of Cd using the refined procedure was 98.9% and the limits of detection and quantification were 0.002 and 0.008 µg L⁻¹, respectively. The within-batch precision values were < 3%. The Cd concentrations in the tissues of the Collembola Isotoma sp. collected from a range of metal-contaminated fields determined by the improved method were consistent with the Cd concentrations in the field soils. The results indicate that the optimized method can be used for more accurate or reliable determination of Cd concentrations in soil micro-arthropod tissues.
... Furthermore, the risk of contamination, the time of digestion and labour input are much higher compared to those of closed vessel mineralization. [31][32][33] Table 1 gives an overview of the wide-spread application of the microwave-assisted digestion procedure for sample preparation of various plant samples (different parts of plants and a wide range of species) and for the subsequent quantication of elements. Apart from the range of analytical applications, the used digestion reagents and solvent mixtures are also provided in this table. ...
Medicinal herbs are nowadays widely used as home remedies for a huge variety of ailments. As non-synthetic medicines, they are considered safe for human health. Due to metal uptake from soil via roots, from air via wet or dry deposition or by contamination during processing, plant materials may contain high amounts of harmful metals, such as arsenic, cadmium or lead. The World Health Organization (WHO) has thus established maximum concentration limits for these elements in order to ensure the safe use of herbs. Therefore, it is important to determine the current metal levels in herbs and their parts used for medical applications in order to determine any potential contamination. These concentrations are in the trace and ultra-trace range; thus analytical experience is needed for appropriate sampling, sample preparation, subsequent measurement by a suitable method and finally the evaluation and interpretation of the data obtained. In the presented review, possible sample preparation methods as well as analytical methods suitable for the given analytical task are summarized and discussed. Based on the sample matrix, the metals to be determined and their expected concentration range, and the sample preparation method as well as the subsequent analytical instrument have to be carefully chosen, optimized and validated.
... This also meant that AAS remained a viable alternative to Q-ICP-MS at the time [28]. Krachler et al., 1996, postulated that spectral interferences could be minimised by removing the organic component of whole blood, leaving only the inorganic material behind for analysis. They showed that by using a closed-system capable of withstanding increased pressure, along with a combination of acid digestion and heating via microwaves, the complete mineralisation of organic matter (in this case, brain and liver tissue) could be achieved, with the organic material being converted into carbon dioxide and water [88]. ...
... Krachler et al., 1996, postulated that spectral interferences could be minimised by removing the organic component of whole blood, leaving only the inorganic material behind for analysis. They showed that by using a closed-system capable of withstanding increased pressure, along with a combination of acid digestion and heating via microwaves, the complete mineralisation of organic matter (in this case, brain and liver tissue) could be achieved, with the organic material being converted into carbon dioxide and water [88]. In fact, the improvements were so notable that the microwave-assisted acid digestion of whole blood has become a routine analytical practice in clinical investigations, where ICP-MS is concerned [19,22,[89][90][91]. ...
In utilising metal surfaces that are in constant contact with each other, Metal-on-Metal (MoM) surgical implants present a unique challenge, in the sense that their necessity is accompanied by the potential risk of wear particle generation, metal ion release and subsequent patient toxicity. This is especially true of orthopaedic devices that are faulty and subject to failure, where the metal surfaces undergo atypical degradation and release even more unwanted byproducts, as was highlighted by the recent recall of orthopaedic surgical implants. The aim of this review is to examine the area of metallosis arising from the wear of MoM articulations in orthopaedic devices, including how the surgical procedures and detection methods have advanced to meet growing performance and analytical needs, respectively.
... The sample digest was diluted, fortified with internal standards, and analyzed using inductively coupled plasma mass spectrometry (ICP-MS, Agilent 7500 Series, Agilent Technologies, Santa Clara, CA, USA). [18] Informed consent for participating in the study was obtained from parents of all cases and the ethics committee of the Karadeniz Technical University Faculty of Medicine, approved this study. ...
Background/Aim:
We aimed to analyze serum hepcidin level in children with chronic liver disease (CLD) and its relationship with serum cytokines level, liver function tests, hepatic iron content, and liver fibrosis.
Patients and Methods:
The study included 34 children with CLD, and 15 age- and gender-matched healthy children. Serum hepcidin, ferritin, iron level, interleukin-6 (IL-6), transforming growth factor-β (TGF-β ), total oxidant status (TOS), and antioxidant status (TAS) were studied in all patients and in the control group. Liver iron content (LIC) was measured from the liver biopsy specimen.
Results:
Serum ferritin levels were higher in patients with CLD than control group (100.1 ± 98.2 ng/mL vs 50.5 ± 32.2 ng/mL, P = 0.016). No significant difference was found in hepcidin levels. Hepcidin levels in children with CLD was positively correlated with ferritin (r = 0.75, P = 0.001), pediatric end-stage liver disease (PELD) score (r = 0.56, P = 0.001), TAS (r = 0.42, P = 0.02), but negatively correlated with albumin level (r = −0.45, P = 0.008). Transferrin saturation and hepcidin:ferritin ratio were significantly low in patients with severe fibrosis compared with patients with mild/without fibrosis (15.5 ± 5.5 vs 34.3 ± 30.1, P = 0.017 and 1 ± 0.5 vs 1.9 ± 1.4, P = 0.04, respectively).
Conclusion:
Serum hepcidin levels in children with CLD reflect both liver functions and TAS, and severe fibrosis is associated with low hepcidin:ferritin ratio in children with CLD.
... Ashokaet al. [3] compared some different method for digestion of fish muscle samples and found that closed microwave-assisted digestion with HNO 3 and H 2 O 2 is the most accurate and precise method for all elements measured except Cr and Ni. The combination of HNO 3 and H 2 O 2 was used in most investigations observed [9,[11][12][13] for microwave-assisted digestion of biological matrices. Additionally, HCl was also applied [10,14]. ...
Reliable determination of elements in raw meat for food is important to control the dietary value and safety of the final product. Atomic spectroscopy techniques, the most accurate analytical methods for elemental analysis, often need the sample preparation step. The main groups of sample digestion methods (dry ashing, hot-block and microwave-assisted acid digestion) were discussed, their advantages and disadvantages were mentioned. We developed and validated two protocols of hot-block digestion of the chicken liver samples in comparison with microwave-assisted acid digestion. The goal was to develop the sample preparation method that would be accurate and precise enough and may be successfully used by laboratories that have no expensive equipment. The following sample preparation methods for ICP-OES elemental analysis were compared: two hot-block digestions (methods A and B) and microwave-assisted digestion (method C). The following acids were used: (1) Aqua Regia (method A), (2) HNO3 with H2SO4 (method B), and (3) HNO3 (method C). Hydrogen peroxide (H2O2) was used in all methods to facilitate organic matter decomposition. It was found that methods B and C lead to a better material dissolution than method A, demonstrating sufficient accuracy and precision values and thus may be recommended for routine use. Method C was time-saving in comparison with hot-block methods and demonstrated less matrix effect than method B. Both of methods, B and C, did not require filtration step before ICP-OES analysis that simplified the sample preparation procedure.
... The total amount of arsenic in chicken tissue samples was determined by microwave digestion ICP-MS according to reference [34]. Each digestion can containing 0.5 g chicken tissues samples was added 5 mL 65% nitric acid. ...
Carboxymethyl α-cyclodextrin immobilized Fe3O4 magnetic nanoparticles (CM-α-CD-Fe3O4) were synthesized for the selectively adsorptive extraction of five phenylarsonic acids including p-amino phenylarsonic acid, p-nitro phenylarsonic acid, p-hydroxy phenylarsonic acid, p-acylamino phenylarsonic acid and p-hydroxy-3-nitro phenylarsonic acid in chicken tissue. Using ultra performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS), a highly sensitive analytical method was proposed for the determination of five phenylarsonic acids. It was shown that CM-α-CD-Fe3O4 could extract the five phenylarsonic acids in complex chicken tissue samples with high extraction efficiency. Under the optimal conditions, a high enrichment factor, ranging from 349 to 606 fold, was obtained. The limits of detection (LODs) (at a signal-to-noise ratio of 3) were in the range of 0.05-0.11 µg/kg for the five phenylarsonic acids. The proposed method was applied for the determination of five target phenylarsonic acids in chicken muscle and liver samples. Recoveries for the spiked samples with 0.2 µg/kg, 2.0 µg/kg and 20 µg/kg of each phenylarsonic acids were in the range of 77.2%-110.2%, with a relative standard deviation (RSD) of less than 12.5%.
... Prior to Q-ICP-MS analysis, the samples were digested and diluted to oxidize and remove organic matter and to minimize the concentrations of inorganic solids (Castillo et al. 2008;Krachler 1996). Three milliliters of each urine sample, 3 mL of Instra-Analysed 65 % HNO3 (J.T. Baker, Germany), and 1.5 mL of Instra-Analysed 30 % H2O2 (Baker) were introduced in Teflon vessels. ...
Prenatal exposure to trace metals, whether they are essential, non-essential, or toxic, must be assessed for their potential health effects in the offspring. Herein is reported an approach to this end which involved collection of urine samples during the first and third trimesters of pregnancy from 489 mothers from Sabadell (Catalonia, Spain), a highly industrialized town. These samples were analyzed for cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), selenium (Se), arsenic (As), molybdenum (Mo), cadmium (Cd), antimonium (Sb), cesium (Cs), thallium (Tl), and lead (Pb). An acid digestion method was developed and validated for inductively coupled plasma quadruple mass spectrometry (Q-ICP-MS) analysis of these 12 metals. The median concentrations of metals ranged from 0.13 to 290 μg/g creatinine, the highest levels were found for Zn and the lowest for Th. The mean concentrations of most metals except As, Ni, Th, and Pb showed statistically significant differences between both trimesters. The concentrations of Mo, Se, Cd, Cs, and Sb were higher in the first than in the third trimester, whereas the opposite was found for Co, Cu, and Zn. The concentrations of all metals in both sampling periods showed statistically significant correlations (p < 0.01 for Mo and Cu, p < 0.001 for the others). The significant correlations of metal urine concentrations in the first and third trimesters of pregnancy suggest that the observed differences between both periods are related to physiological changes. Accordingly, the measured urine concentrations during either the first or third trimesters can be used as estimates of exposure during pregnancy and can serve as markers for prenatal intake of these metals in the studied cohort.
... The brain collected at 20 days following this treatment. Digestion of dry brain samples was performed in a medium with nitric acid and 30% hydrogen peroxide (Krachler et al., 1996). The lead acetate content in brain homogenates was measured by atomic absorption spectrophotometry (Perkin Elmer 1100 B) (Chakraborty et al., 1996). ...
Environmental exposure to toxic levels of lead (Pb) occurs in a number of industries with potential adverse effects on the reproductive capacity of exposed men. Clinical and animal studies indicate that abnormalities of spermatogenesis result from toxic lead exposure, but eventual histopathologic alterations involved have not been identified. To explore putative abnormalities in the reproductive gonadotropic axis following lead intoxication, experimental animals when exposed to low levels of lead, 65 days old animals were treated with distilled water containing 0, 0 mg (control), 10 mg lead (Pb)/Kg/day and 15 mg lead (Pb)/Kg/day intraperitoneally for 20 days. At the end of treatment, the animals were sacrificed and the blood collected for luteinizing hormone (LH) and testosterone assays. The testis was processed for histological analysis. The results showed a high serum concentration of LH and testosterone in lead-treated animals compared to controls. Histological examination of testis showed deformities in testicular morphology of lead intoxicated animals with gross damage within the somniferous tubules. A strong correlation was established between LH and testosterone suggesting an alteration in the endocrine components of the gonadotropic axis. Histological examination of pituitary gland showed some degenerative changes in endocrine cells of lead group. Changes in LH and testosterone levels suggest that Pb exposure during the critical time of sexual differentiation induces reproductive axis abnormalities in adulthood. In conclusion, lead has a gonadotoxic effect by decreasing LH and testosterone levels and damaging the testis seminiferous tubules. Catalase activity was significantly reduced in the lead group following 65 days of exposure which possibly indicates that lead might had other mechanisms of action, such as increasing oxidative damage.
... The investigation of heavy metals in herbal products is widely fascinated. Inductively Coupled Plasma Mass Spectrometry (ICP- MS) has been proved to be the technique of choice to analyze herbal medicines for metals (Krachler et al., 1996). High contents of As, Cd, Pb and Hg in plants may also be accredited to the uptake of these elements from polluted soil primarily due to anthropogenic activities. ...
Artemisia annua and Pyrus pashia are used to relieve and treat many human diseases due to their low side effects. They are rich source of biologically important elements, which may play an important role in the observed therapeutic uses of these plants. It is important to have a good quality of medicinal plants in order to protect consumers from contamination. Therefore, the aim of the present study was to carry out a comparative evaluation of heavy and essential metals contents in A. annua and P. pashia. The heavy and essential metals (As, Cd, Zn, Ni, Pb and Hg) contents ranged between 1.82±0.54 - 1.86±0.22, 0.30±0.07 - 0.36±0.15, 18.00±3.32 - 27.00±2.53, 1.22±0.44 - 3.02±0.55, 1.24±0.54 - 1.84±0.42 and 1.60±0.84 - 1.92±0.35 mg/kg respectively in A. annua, while for P. pashia these varies from 2.65±1.83-2.81±0.25, 0.02±0.06 - 0.05±0.25, 13.50±3.13 - 25.20±1.18, 0.21±0.82 - 2.42±0.24, 0.38±0.03 - 1.05±0.08 and 1.48±0.78 - 1.82±0.46 mg/kg respectively. The highest Cd, Zn, Ni, Pb and Hg content was detected in roots of A. annua, while highest concentration of As was found in leaves of P. pashia. The contents were well within the permissible limits therefore, it can be used in the cure system.
... This type of procedures allow a complete destruction of the solid samples matrix, so the digest can be easily analyzed using conventional sample introduction systems in different techniques for mineral determination. Microwave digestion methods have become popular because they are more reproducible, more accurate, and less time-consuming than conventional digestions on hot plates in open beakers [11]. A partial vapor-phase acid digestion procedure is proposed using a focused microwave oven operating at atmospheric pressure for Fe and Co determination in biological samples (including bovine liver 1577b) by electrothermal atomic absorption spectrometry (ETAAS). ...
... Digestion parameters (mass of sample, digestion mixture, and power/time steps) were optimized. Digestion with the open-focused microwave system requires larger volumes of nitric acid and hydrogen peroxide, and the detection limits are higher than the system with the closed-pressurized digester [11]. A partial microwave-assisted wet digestion (HNO 3 + H 2 O 2 ) using a baby-bottle sterilized with a domestic microwave oven was compared with a total microwave-assisted wet digestion using a commercial microwave digestion system. ...
