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Instrumental Methods of Analysis 1. Introduction PowerPoint Presentation
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Instrumental Methods of Analysis 1. Introduction

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  1. Instrumental Methods of Analysis 1. Introduction • Writing Intensive • Rewrites are Required • Large Amount of Excel Data Management • Work • Individual • Work Log • Own Sample • Exams • Lab Book pages • Group • Division and Attribution of Labor (Accountability) • Reports • Calibration Curves • Single Analyte (Skill Development and Cross Comparison Methods) • Overlapping Themes • Statistics/Sampling • Solution Chemistry • EDTA • Isotopes • Phase Separations

  2. Instrumental Methods of Analysis 1. Introduction • 1. Writing Intensive • 2. Work • 3. Single Analyte • 4. Problem Based • What is best method for lead analysis? • What is best method for This particular sample? • 5. Ethics and Service Learning • How do we know? • Critical Thinking

  3. Confusion Confusion Electronics, Spectroscopy, Electrochemistry, Chromatography “Too much from instructor” information 7 different analytes 7 different methods Iodide Electrolysis Chromium & permanganate UV-Vis How do we select Or compare methods/ Instruments? Methanol Gas Chromatography Quinine Fluorescence Fluoride Ion Selective Electrode DMSO Infrared Spectroscopy CuGraphite Furnace Atomic Absorption

  4. Figures of Merit Theme Knowledge Choose Method: Cross Compare/measure LOD PbLimit of detection? PbLinear range? PbSelectivity? PbSignal/Noise? Calcein Blue PbFluorescence Quenching Role of solution pH important PbAnodic Stripping Voltammetry Pb Dithizone UV-Vis PbAtomic Absorption 207Pb in EDTA by proton NMR PbIon Selective Electrode Tetraethyl 207PbMS EDTAPbHPLC PbEDTAInfrared Spectroscopy

  5. Week Topic “Lab” Concept Stat Chem Isotope Ethics 1 Pb & Society; Statistics and Ethics Pototo populations x x 2 Signals & Noise; LOD Analog & Digital filters x 3 Relevant Chemistry; Exam I ISE & Pb(OH)2 x 4 Intro Spectroscopy IR & UV-Vis x 5 Molecular Spectroscopy IR & UV-Vis x 6 Fluorescence and AA Fluorescence and FAA x x 7 AA and Vibrational, Exam II Fluorescence and FAA x x 8 Break, NMR Break 9 NMR, Off campus sampling NMR, ASV x x x 10 MS, NMR, ASV x x x 11 Intro Electrochem., Select Methodsample prep x x x 12 Potentiometry, sample analysis x x 13 ASV, Take home exam III ICP-MS, GC x x 14 Separations ICP-MS, GC x x 15 Separations How do we know? Ethics x x

  6. Why Lead? Health

  7. Same size, Shape, chemistry Different Orbitals, Different total Number of electrons

  8. Warren et al, TIBS, 1998, 23, 217

  9. Current measurements no longer rely on zinc protoporphyrin as PbB effects on fetal development can be detected at values of PbB <5 ug/dL

  10. An estimated 40% of lead in blood plasma bound to ALAD Wetmur, 1994 ALAD dehydratase with lead binding site

  11. Enhanced ALA concentration leads to tautomers which easily form radicals which may attack the cell wall - leading to early cell death. Heme dies about 20% earlier Hammond and Dietrich, 1990

  12. Because lead affected ALAD resulting in overproduction of ALA ALA may also affect the function of GABA but a close similarity in molecular structure GABA controls leaf tip growth, and brain development. Function changes with time, so growing tips and infants differentially affected from adults

  13. Herlenius and Lagercrantz, 2001 Ben-Ari1, 2001 Certain portions of the brain more greatly affected: prefrontal cortex: problem solving hippocampus (memory) cerebellum (motor coordination, body movement, posture and balance)

  14. Why Lead? Everywhere

  15. Lead as an ore in the earth relatively benign Human activity distributes lead into the environment

  16. Modern major uses 1. Pigments 2. Leaded Gasoline 3. Munitions

  17. Eliminating Childhood Lead Poisoning: A Federal Strategy Targeting Lead Pain Hazards, Feb. 2000

  18. Other Ecosytem Impacts of Lead To air Mine Deposit elsewhere Deposit locally Fishing sinkers & shot incinerate Sewage sludge ash reclaim Cementblock landfill Flow to groundwater fertilizer Bottom sludge Plant uptake groundwater

  19. 2009 Class Project

  20. GrowingScientists S. 1994 20 5th graders map park soil lead Northwest Incinerator F 1994 Austin homes: Yard Soil Lead Northwest Incinerator F 1995 Grid map House Dust House Dust F 2002 F 1996 Uptown 5th graders sample and tour labs West Pullman White Lead factory Northwest Incinerator F 1998 Tight grid and isotopes F 1997 House Dust Bethel New Life: Brownfield F. 1999 Little village Boys and Girls Club (failed) Soil sampling Orozco School: House Dust F 2000 Pullman: White Lead Factory F 2001 National Award for The Class Loyola Chem Sr. ACS Mtg poster S 2008 Lead in Toys Evanston Childcare Alanah Fitch afitch@luc.edu

  21. Lead Elimination Action Drive West-side Alliance for a Safe Environment (WASTE) Center for Neighborhood Technology Austin Neighborhood Council Homes Municipal Waste Incinerator Pb? Incinerator 1994, 1995, 1998

  22. Wind Decreasing amts Background Soil lead “Shadow” depends on Stack height Largest deposition Is here Incinerator 1994, 1995, 1998

  23. Control Students meet with elderly ladies who let them sample soils. The ladies discuss their concerns. sampling Incinerator 1994, 1995, 1998

  24. Soil Lead in parts per million (ppm) 1850 1385 250 150 Front 1040 187 440 4822 W. Potomac 4833 W. Crystal 4915 W. Kamerling Back 1800 1431 231 372 garage Incinerator 1994, 1995, 1998

  25. Comparison homes, 17 mile away 2620 1133 2808 2900 3067 1538 439 700 6729 N. Ashland 6613 N. Ashland BRICK FRAME Incinerator 1994, 1995, 1998

  26. Second year: Resample with respect to the wind; also allowing for up and down wind comparisons. Wins a National Award. Luke later goes to Croatia On UN project on Lead dispersion by gasoline Incinerator 1994, 1995, 1998

  27. This data presented To Mayor’s advisory council North Wind Pattern 32 101 Class final: enter Busch National Env. Award competition – Place third 23 12 Chicago 89 82 123 1210 Orr High School 546 346 644 m 15 Demolished lot Pulaski 320 42 Cicero Washington 0 Incinerator 1994, 1995, 1998

  28. > 0.5 mile from incinerator < 0.5 mile from incinerator Incinerator 1994, 1995, 1998

  29. Wind Decreasing amts Background Soil lead “Shadow” depends on Stack height Largest deposition Is here Incinerator 1994, 1995, 1998

  30. Last time: we finally set up an experiment worthy of an An air pollution expert NE NNE N ENE E SE Incinerator 1994, 1995, 1998

  31. Across • the system of pipes and other apparatus for conveying water, liquid wastes, etc., as in a building • the fluid that circulates and carries oxygen throughout the human body • being placed at risk • 8 the quality of degree of being toxic or harmful to plants or animal life • 9. the introduction of harmful substances or products into the environment • a mixture of pigment and liquid • 12. food, eating healthy • 14. a pain located in the head • 15. the age group affected most by lead poisoning • 17. President on the $20 bill • a transparent, odorless, tasteless liquid, a compound of hydrogen and oxygen, H20, that constitutes rain, oceans, lakes, rivers, etc. • . to take ill through eating • Down • 2. a heavy, comparatively soft, malleable, bluish‑gray metal. A toxic metal, that has been widely used in paints, plumbing and fixtures, and in some water supply service lines • 3. composer thought to have had lead poisoning • 5. the portion of the earth's surface consisting of dirt • 6. the air, water, minerals, organisms, and all other external factors surrounding and affecting a given organism at any time • 7. dry particle of earth • a table illustrating the periodic system, in which the chemical elements are shown in related groups • . the process of preparing the samples by breaking down the baby wipes into a substance suitable testing • 13. a silver‑white divalent metal found in limestone, chalk, milk • 16. the science that deals with the composition and properties of substances and various elementary forms of matter