EVALUATION OF PYRO CUBE FOR DEUTERIUM OF HAIR By Paul Middlestead and Michelle Chartrand Ottawa University , G.G. Hatch Lab At the request of Paul Brooks, thanks big guy Calgary, Asita 2013, 19th edition and still going… WHAT IS A PYROCUBE ? From elementar: vario PYRO cube Note: No endorsement from this guy. All manufacturers make products that (usually) deliver. In this case, the PYRO is an alternative to the TC/EA in our lab. Both systems are fine and well supported. The PYRO is newer on the market and this is a preliminary evaluation • Ceramic and Glassy carbon tubes : 30mm and 18mm • Glassy carbon chips packing + soot • Bottom feeder • Purge and trap separation • Crucible: 2,0 cm3+ (400 samples) • TCD + software + computer • 120/80 samples heated caroussel (open, large holes) • 125ml/min flow • Furnace on steroids + brain • Can be upgraded to CNS • Sleep mode • Ceramic and Glassy carbon tubes : 18mm and 12mm • Glassy carbon chips packing • Bottom feeder • GC column separation 5A • Crucible: 0,75 cm3 (200 samples) • No TCD, no software, no computer • 30/50/100 samples caroussel (close, small holes) • 80ml/min flow • Furnace on steroids IRMS IRMS 100 ml/min TCD • • • • • • 2-3 mm He 25 ml/min IRMS Bottom feeder independant flush, 130ml/min More space between glassy carbon and ceramic Fresh He for CO desorption on chemical trap Bypass for Hydrogen mode TCD for % of H2 and Oxygen Carrier flow of 125ml/min Different modes, different packings • O mode: CO column in line, H is ignored • H-O mode: CO column in line • H mode: No CO column in line H mode reactor No CO column We found Hmode packing to work well in all modes Crucible Glassy carbon chips Ag wool Qtz wool Bottom connector H-O mode reactor CO column Crucible Carbon black Graphite felt Glassy carbon chips Spacer Qtz wool Bottom connector O mode reactor CO column Crucible Carbon black Glassy carbon chips Graphite felt Spacer Qtz wool Bottom connector Bigger is better ? • • • • Larger tubes = more surface = less repacking Larger crucible = more area = less cruciblication Larger tubes = more surface = smaller peaks Larger tubes = more $$$$ but last longer… Wake up! Have you noticed the major difference with the PYRO in H mode? • Something unthinkable • Something not usually seen or used • Something unnatural for analytical reason • Hint: no divorce IRMS Bypass of CO column… No separation between CO and H2 Typical TC/EA run Flow: 95ml/min GC temp: 90C Peak width: 80s Peak height: 10,6V Peak area: 93,5 Typical Pyro run O-H mode WHY SMALLER? Flow: 125ml/min Peak width: 78s (80) Peak height: 4,6V (10,6) Peak area: 51,5 (93.5) LARGER VOLUME + FASTER CARRIER FLOW (i.e.dilution) ADDITION OF SOOT: MAGICAL….without fractionation Typical Pyro run O-H mode, TCD Typical Pyro run H mode Flow: 125ml/min Peak width: 88s (80) Peak height: 7,0V (10,6) Peak area: 76 (93.5) No CO column! No soot Typical Pyro run H mode, TCD USELESS OMG, this is so cool ! For fun, O-mode only, TCD IGNORED ! Pyro linearity -60 0 5000 10000 15000 20000 25000 -65 -70 -75 -80 Series1 -85 -90 -95 -100 Hair, 0,051 to 1,000 mg TC/EA linearity -92 0 5000 10000 15000 20000 25000 30000 35000 -94 -96 -98 -100 -102 -104 Series1 For Deuterium , what standards? First: It is imperative to normalise using a decent spread of values for Deuterium analysis, best to bracket the samples with standards of similar matrix. For Deuterium , what standards? • • • • • • • Polyethylene foil IAEA-CH-7 -100.3 YES Oil NBS-22 -117 (?) Biotite NBS-30 -66 (?) Some hair now available from USGS: USGS 42: -78,5 USGS 43: -50,3 Water stds in Silver capillaries (thanks Ty) Sweet nothing KAOLINITE Kga-1: -58 Methodology for hair (or exchangeable material) -212 16 AUTOSAMPLER Light water (vsmow) Heavy water (vsmow) Difference -212 16 228 Hair Water Measured (vsmow) %= diff value*100 diff water John Light -86,6 John Heavy -58,6 = (-86,6+58,6)*100/228 = 12,3% or 0,123 Hair – water exchanged True = measured-(percent * water) 1 - percent Final John Light True light = -86,6 - (0,123 * -212) 1 – 0,123 69,0 John Heavy True heavy = -58,6 – (0,123 * 16) 1 - 0,123 69,0 First, check the standards! Standard Deuterium values (raw) PEF Light (-212) 336,0 PEF Heavy (-16) 335,6 PEF Off Bench 336,4 Kga-1 Light (-212) 398.1 Kga-1 Heavy (-16) 400,5 Kga-1 Off Bench 399,0 NO EXCHANGE !!!!! Raw Deuterium values 0 200 -20 250 300 350 400 450 y = 0.6689x - 325.07 R² = 0.9965 -40 -60 Y-Values Linear (Y-Values) -80 -100 -120 This PYRO curve is exactly as all others curves done on TC/EA Just for fun NBS-30 Biotite test: -61,4 -63 (-66) Not bad, this is a tough cookie! Lets not split hairs! Real hair test Hair Percent exchanged TC/EA Percent exchanged Pyro Diff with real value TC/EA Diff with real value Pyro John 12,3% 6,1% 2,6 -9,7 Paul 12,9% 7,4% 2,4 -7,1 Ringo 11,2% 7,3% 0,6 -7,3 George 12,9% 5,9% 2,3 -8,4 Samples back-exchanged with air in auto sampler Conclusion • • • • • Pyro peak, in H mode, is about 80% of TC/EA Run time of Pyro is about 50% shorter (H-mode) Same calibration equations Pyro appears to be less linear, but better in low range Very comparable instruments • Higher output: faster running, less down time • No zero blank auto sampler: back exchange of H We would like to thank: Paul Brooks, Wendy Abdy, Patricia Wickham, Gilles St-Jean, Scott Hughes, Robin Sutka and the Gods of Pyrolisis.