Trace element analysis of plant material Lab Report XRF 445 - Bruker

InstrumentationRecovery of macronutrients by TXRFAll measurements were performed usingthe benchtop TXRF spectrometerS2 PICOFOX. This instrument is equippedwith an air-cooled low power X-ray tube (Motarget), a multilayer monochromator with80% reflectivity and the liquid nitrogen-freeXFlash ® silicon drift detector (SDD) with anenergy resolution of

NIST leave standards tomato, apple, peach and citrusComparison of TXRF and reference concentrationsDetection limits for trace elements in plant materialFig. 3: Comparison of TXRF and reference values for other traceelements in plant standards; NIST 1515: V, Br, Rb, Sr, Ba, La, Ce, Nd, Pb;NIST 1547: V, Br, Rb, Sr, Ba, Ce, Pb; NIST 1572: Cr, Br, Rb, Sr, Pb;NIST 1573a: V, Cr, As, Br, Rb, Sr, BaFig. 4: Detection limits for trace elements in plant standardsdetermined by TXRF analysisConclusionsThe analysis of trace elements in plant material can beeasily performed with TXRF spectrometry. TXRF doesnot require any time-consuming sample digestion withhazardous chemicals. Just a simple grinding step followedby preparation of a suspension allows a fast and accuratemulti-element analysis.An unique highlight of TXRF analysis is the ability tomeasure smallest sample amounts. Rare plant material ormedical herbs can be directly and quantitatively preparedin a micro reaction vial as described in the text box on thelast page.Macronutrients available in higher concentrations can bemeasured from low ppm concentrations up to the percentrange with an accuracy of about 5 %. For micronutrientsand other traces detection limits down to 100 µg/kg can beachieved.

ReferencesPreparation of micro samples in a mixer mill[1] Hansen, T.H. et al. (2009) “Micro-scaledhigh-throughput digestion of plant tissuesamples for multi-element analysis”, PlantMethods, 5:12AcknowledgementThe following photos are published on WikimediaCommons under free documentationlicense (GFDL): “Tomato” from David Besa,USA; “Apple” from Fievet, France; “Peach”from Lucien Monfils, Netherlands; “Citrus”from H. Zell, Germany.Smallest amounts of sample,such as are normally used forthe analysis of medical herbs oranimal tissues, can be preparedin disposable reaction vials.Adapter racks of PTFE whichaccommodate either 5 or 10disposable reaction vials can beused for this. In the mixer mills(e.g. Retsch MM 400), samplesare ground so quickly and efficientlythat no additional cooling isnecessary.The quantitative sample preparationfor micro samples is asfollows:Authors• Weigh a few mg of sampleand take a note of the exactweightHagen Stosnach, Armin Gross,Bruker Nano GmbH, Berlin, Germany• Add Triton X-100 and internalstandard• Homogenize in mixer mill• Pipette 10 µl suspension on aquartz sample carrierAll configurations and specifications are subject to change without notice. Order No. DOC-L81-EXS045, Rev. 1.1.© 2013 Bruker Nano GmbH. Printed in Germany.Bruker Nano GmbHBerlin · GermanyPhone +49 (30) 670990-0Fax +49 (30) 670990-30info@bruker-nano.dewww.bruker.comBruker AXS GmbHKarlsruhe · GermanyPhone +49 (721) 50997-0Fax +49 (7 21) 50997-5654info@bruker-axs.deBruker AXS Inc.Madison, WI · USAPhone +1 (608) 276-3000Fax +1 (608) 276-3006info@bruker-axs.com