High Pressure Asher

Decomposition in closed quartz or glassy carbon vessels at high pressure (up to 120 bar) with conventional heating [45 7] High Pressure Asher (Anton Paar Company, Graz, Austria). 

Instrument Company systems apply microwave heating, whereas the High Pressure Asher has a conventional heating system. 

High Pressure Asher HPA (Pressure decomposition in quartz vessels) ... 

A rapid, robust ICP-MS method was described for the determination of I in food for human consumption as well as for pets [34], The sample preparation was made by alkaline hydrolysis with TMAH using either MW heating or the high-pressure asher. Method validation was carried out using seven food CRMs with certiPed I content and by cross-validation with GC, neutron activation analysis (NAA) and colorimetry. The method has been proven to give accurate and repeatable results for a range of fortiPed food commodities for human and animal consumption. 

ICP-AES Condensed milk MW digestion and high pressure asher... 

High pressure asher autoclave High pressure asher autoclave... 

Matusiewicz, H. Development of a high-pressure asher focused microwave system for sample preparation. Anal. Chem. 71, 3145-3149 (1999)... 

Amaarsiriwardena, D., Krushevska, A., Argentine, M., Bames, R.M. Vapour-phase acid digestion of micro samples of biological material in a high-temperature, high-pressure asher for inductively coupled plasma atomic emission spectrometry. Analyst 119, 1017-1021 (1994)... 

Teas, tea RM PSKCaTiMn Fe Ni Cu Zn Se Rb Sr Ba Pb Closed vessel wet digestion with HNO3/ HCl in quartz tube in High Pressure Asher [WDCCV] Evaporate solution on quartz glass [WDCCV-EDTXRF] carriers, measure with energy dispersive spectrometer [EDTXRF] Xie et al. 1998... 

Total diet samples (Swiss), food and plant CRMs, RMs I Add digest in high pressure asher autoclave with HNO3 [WDCCV] Determine with ICP-MSr with microautosampler and low uptake nebulizer [IDICPMS] [WDCCV-ID- ICP-MS] Haldimann et al. (2000)... 

Weigh or pipette 2 mL of the specimen into the quartz vials available for use in the high pressure asher. Add 3 mL nitric acid (suprapure 65% v/v) + 0.2 mL perchloric acid (70%v/v) -I- 0.2 mL H2O2 (30%). Close and heat the chamber to a temperature of 320°C for 4 h. Cool and dilute the contents to 10 mL with ultrapure water. 

The 69% nitric acid (HNO3) and 37% hydrochloric acid (HCl) used for sample dissolution in a high pressure asher (HPA-S, Anton Paar, Austria) were supra grade quality purchased from Roth (Karlsruhe, Germany). The 40 % hydrofluoric acid (HF) used to remove silicates was of suprapure grade from Merck (Darmstadt, Germany). 

Generally applicable decomposition procedures for organic, biological, and environmental samples are discussed in [16,20,21]. The samples are digested in a high-pressure asher using mixtures of nitric and hydrochloric acid. Mixtures of hydrochloric, nitric, and perchloric acid are used for the decomposition of blood, blood plasma, and urine samples [16]. The procedures described also apply to ultratrace analysis in the ng/kg concentration range. 

Examples of almost completely mineralizable matrices include resistant inorganic and high-fat organic samples. Nevertheless, limitations with respect to subsequent use of electrochemical methods of determination (Section6.2.5.1) still represents a critical problem [52], and the results are often inferior to those from a conventional high-pressure asher (HPA). 

---