Chem415 Quantitative Bio-Element Imaging Center (QBIC): Part I APRIL 10, 2015 DIRECTOR: PROFESSOR THOMAS V. O’HALLORAN MANAGING DIRECTOR: KEITH MACRENARIS, PH.D 1

History and Mission of CLP and QBIC  “The Chemistry of Life Processes Institute acts as an umbrella for a variety of centers, facilitates collaborations and helps bridge different cultures. By lowering the barriers to scientific discovery, the Institute hopes, for example, to design new drugs for the treatment of cancer and neurodegenerative diseases as well as develop improved techniques for diagnosing diseases earlier.”  Designed to be a collaborative, interdisciplinary effort to map the “inorganic signatures of life”  Started in 2003 and established as an official center within the Chemistry of Life Processes Institute in September of 2008  CLP includes 39 tenure-track faculty members and 11 cores and centers  Elemental Analysis is located in Silverman Hall East Room B540  Microscopy is located in Silverman Hall East room

How to Map the Inorganic Signatures of Life Elemental Analysis Using high end instrumentation for quantitative metal analysis to determine metal concentrations in solutions, materials, cells and tissues. Imaging Using one-of-a-kind STEM, 2-photon laser scanning microscopy, and laser ablation ICP-MS for elemental mapping in tissues and cells Collaboration The synergy with Argonne National Laboratory and the Advanced Photon Source for Hard X-ray Fluorescence Microscopy for subcellular trace elemental mapping 3

Emission Ratiometric Imaging of Intracellular Zinc J. Am. Chem. Soc., 2004, 126 (3), pp 712– nm using 2-photon laser No treatment + 10 µM zinc sulfate+ 1 mM TPEN 4

Choosing the Correct Analytical Technique I 5

Choosing the Correct Analytical Technique II 6

Atomic Absorption Spectroscopy Quantitative determination using absorption of optical radiation (light) by free atoms in the gaseous state. Electrons of the atom can be promoted to higher orbitals by absorbing radiation of a given wavelength (specific to an electron transition of a particular element). The radiation flux with and without a sample in the atomizer is measured using a detector resulting in absorbance at a particular wavelength. 7

Flame Atomic Absorption Spectroscopy (Flame AA or AAS) 8

Flame AA in QBIC 9

Lamp Types for AAS 10 Hollow Cathode Lamps Electrodeless Discharge Lamps

Graphite Furnace (Electrothermal) Atomic Absorption Major limitation for flame AA is burner-nebulizer system is relatively inefficient so only a small fraction of the sample reaches the flame where the atomized sample passes quickly through the light path. Improved sampling device would atomize the entire sample in the light path for an extended period of time enhancing the sensitivity of the techniques 11

Steps in Atomic Absorption Flame AAS  Desolvation (drying) – solvent is evaporated and dry sample nano- particles remain  Vaporization (transfer to gaseous phase) – solid particles are converted into gaseous molecules  Atomization – molecules are dissociated into free atoms  Ionization – Atoms may be converted to gaseous ions (not necessary for analysis) GFAAS  Desolvation (drying) – solvent is evaporated and dry sample nano- particles remain  Pyrolysis – Majority of the matrix components are removed  Atomization – Analyte element is released into the gaseous phase  Cleaning – Residue in the graphite tube is removed at high temperatures 12

Uses of Atomic Absorption  Flame AA is becoming rarer due to the lower cost of purchase and operation of more advanced analytical techniques (i.e. GFAAS and ICP)  GFAAS has been an established techniques for more than 40 years especially in the food industry and for clinical samples  Many EPA and FDA analytical methods are approved using GFAAS  GFAAS very useful for samples with very limited volumes (< 100 µL) 13

Choosing the Correct Analytical Technique III 14

Analytical Advantages of ICP over AA? 15

Information  For elemental analysis Keith MacRenaris at  For STEM/EDS analysis Reiner Bleher at  QBIC website:  NUANCE website: 16