Glass cyclonic spray chamber

The multi-element analysis was performed on a NexION 300X ICP-MS spectrometer, equipped with a S10 autosampler, a glass concentric nebulizer, a glass cyclonic spray chamber, and a kinetic energy discrimination (KED) collision cell, all produced by Perkin Elmer (Milan, Italy). Samples were mineralized by means of a microwave single reaction chamber (SCR) system (ultraWAVE™, Milestone, Sorisole, Italy) equipped with fifteen polytetrafluoroethylene (PTFE) vessels (volume: 15 cm³ each). An Ultraturrax mixer model T18 (IKA, Staufen, Germany) was used to homogenize the honey samples before analysis. The residual acidity and the dissolved organic carbon (DOC) in the digested sample were determined by acid–base titration procedure and by the Walkley-Black method [65 ] using a Thermo Scientific Orion 950 titrator, whereas the total organic carbon (TOC) was determined by means of a CHN analyzer Leco 628. Nylon filters (pore diameter: 0.22 μm), polypropylene (PP) metal-free tubes, and polyethylene (PE) flasks were from VWR (Milan, Italy).

Trace and toxic elemental analyses were performed on a NexION 300X ICP-MS (inductively coupled plasma mass spectrometry) spectrometer equipped with an S10 autosampler, a glass concentric nebuliser, a glass cyclonic spray chamber, and a kinetic energy discrimination (KED) collision cell, all produced by Perkin Elmer (Milan, Italy). Macro elemental (Na, Mg, K and Ca) analysis was performed on an AAS (Atomic Absorption Spectrometry) analyst 200 spectrometer, produced by Perkin Elmer (Milan, Italy). The analysis of total phosphorus was carried out using the colorimetric method, by reacting an aliquot of the mineralised sample extract with phosphomolybdic reagent reduced with ascorbic acid. The colouration, developed from the reduced phosphomolybdic reagent reaction, was then measured using an Agilent Cary 60 fibre optic spectrophotometer, referring to a previously prepared calibration curve. Samples were digested using a microwave single reaction chamber (SCR) system (ultraWAVE™, Milestone, Sorisole, Italy) equipped with fifteen polytetrafluoroethylenes (PTFE) vessels (volume: 15 cm³ each).