Home Page and Syllabus for Chem 454

Instrumental Analysis – Spring 2023

Frank Cheng, Renfrew 003, 885-6387, ifcheng@uidaho.edu

TA for Lab: TBA.

Office Hours 1:00-3:00 MW, You are welcome to stop by and ask questions anytime.

Cheng Group Web Site Link To Chem 454 Labs

What is Analytical Chemistry? “measurements used to assure the safety and quality of food, pharmaceuticals, and water; to assure compliance with environmental and other regulations; to support the legal process; to help physicians diagnose diseases; and to provide measurements and documentation essential to trade and commerce.”

Historical Example of Analytical Chemistry: The Touchstone, James Burke Connections Ep 2. 1:00 – 5:00, The Lydians, Leviticus 19:35-6 and Quran Mohsin Khan 11:85

Analytical Chemists make measurements that directly affect people’s lives, judicial outcomes and well-being.

Ethics of Clinical Chemistry “The work performed by the clinical chemist may deeply affect the decisions of the doctor and the well-being of the patient. Yet in contrast to the doctor and to the nurse the clinical chemist usually has no personal relationship with the patient.” Link 2, 3. Careers in Clinical Chemistry.

Ethics of Forensic Sciences – Book, DOJ - NIST

Recommended Texts - Recent Editions of:

Principles of Instrumental Analysis, Douglas Skoog et. al, Contemporary Instrumental Analysis Rubinson and Rubinson, Quantitative Chemical Analysis, DC Harris, Analytical Chemistry 2.1

Outline and Web Links, Subject to updates through the semester.

1. Introduction and Review of Statistics and Error Analysis

1.1 Basic Nomenclature * Technique vs. Method * Qualitative v. Quantitative * Accuracy v. Precision * Analyte v. Sample * Interferent

1.2 Chem 253 v. Chem 454 * ‘Wet’ Techniques & Methods

Analyte Concentrations, typical 1-10%

Accuracy +/- 0.1% or 1 ppt

Precision 1%

Instrumental Techniques & Methods

Analyte Concentrations, typical 1ppt to 1ppm or less

Accuracy +/- 10%

Precision 10%

1.3 About Horwitz’s Trumpet (link 2, 3)

1.4 Standard Deviation. z-score. In Graphs. Bad example.

1.5 Student’s t-Test

1.6 Method of Standard Addition - Journal of Chemical Education 1980, 57, 703, Search for least squares tutorial from Yahoo

1.7 Grubbs Test for Outlier (Calculator)

1.8 Detection limit (calculator), LOD, other definitions in Clinical Chemistry, Univ. of Tartu, Signal to Noise Demo (1:29 to 1:50)

1.9 Sensitivity * Background and Noise * Linear Range * Dynamic Range

1.10 Method of Least Squares * Correlation Coefficient * Calibration Curve * Standard Addition * What’s the difference between calibration curve and standard addition? * When should you a calibration curve vs. standard addition? * Matrix Effects

Spurious Correlations.

Video: An Analytical Chemist Gone Bad. Another One.

Flawed FBI assumptions about bullets (1, 2, 3, 4, 5) NAP on Trace Elements in Lead Bullets.

Adding taggants to explosives.

Fluorescent Tags for DNA.

Molecular and Atomic Spectroscopy at ASDL

2. Spectrophotometry – Spectrometer vs. Spectrophotometer (Link 2)

2.1 Electronic Transitions * Electromagnetic Spectrum * Spectroscopy * Spectrophotometer * Jablonski Diagram (link 2, 3)

2.2 Atomic Spectra NIST Database vs. Spectrum of Benzene Vapor vs. Benzene in Hexane – Why the difference?

2.3 Beer's Law

2.4 Stray Radiation & Example

2.5 Noise Libretext * 60 Hz YouTube * Noise & Hear the Noise* 1/f Flicker Noise or pink noise and its appearance in nature*Light Chopper and 1/f noise

Shot Noise J. Chem. Ed., 2014,91,1455-1457 * 1/f and Shot Noise Power Spectrum (see Fig 1.), Youtube, What is the difference between thermal and shot noise?

Environmental Noise, 60 Hz

2.6 Noise Filters 60 hz notch* Faraday Cage - Wikipedia, A demonstration from Youtube

2.7 Luminescence * Fluorescence and Structure * Excitation vs. Emission Spectra * Chemiluminescence – Luminol detection of iron in blood at crime scenes (Link 2)

3. Components of Optical Instruments.

6.1 Sources: Blackbody Emission, D₂ Lamp*W Lamp (2)*D₂, W Emission Spectra*Xe Arc Lamp*Hg vapor Lamp

6.2 Wavelength Isolation: Double Slit Experiment*Echelle & Echellette (Link 2) Gratings Demo*Interference Filter*Monochromator (1, 2), Video.

6.3 Transducers: Photomultiplier Tube (1,2)*Photodiode Array*Charged Coupled Device*Single Beam Spectrophotometer*Dual Beam Spectrophotometer*Diode Array Spectrophotometer a (description)*CCD Array Spectrophotometer * CCD vs. PDA * CCD Video * Libretext on Photon Detectors

Science Magazine Review of Miniaturized Spectrophotometers.

4. IR/FT-IR

7.1 General Theory (Libretext) * Wavenumbers

7.2 IR Source: Globar * Sample holders * IR Regions, NIR, Database of Common Organics from NIST, Applied Spectroscopy,

7.3 Example of Analyses Using IR * Wood * Wheat from UI Ag Extension * MTBE in Gasoline. MBTE Plumes, ASTM * Explosives *Ethanol in Gasoline*Chemical agents*

7.4 Detectors – Ewing’s Analytical Instrumentation Handbook *Heat Detectors-DTGS, TGS*Photon Detectors-PbS, InSb, HgCdTe*Video

7.5 FT-IR - Wikipedia*History and Theory*Libretext*Hardware*Interferometer Animation

7.6 Apodization – Math from Wikipedia, “Ringing” also Wolfram Research, From Columbia U (see figure 10)

Signal Averaging – Chemometrics In Analytical Chemistry.

5. Raman

8.1 Introduction – Renishaw*Wikipedia*Venkata Raman Bio

8.2 Rayleigh Scattering, Stokes Lines

8.3 Lasers (link 2, 3, 4) types, laser efficiency.

8.4 Why FT-Raman has not overtaken dispersive Raman. Link 1, 2, 3

8.5 Example of MTBE analysis with Raman * Forensic analysis of inks using a Raman microscope (Blood Samples). Of cocaine on fingernails. Counterfeit currency.

6. Atomic Spectroscopy

9.1 Libretext*Atomic Absorption *RSC start on page 2

9.2 Components: Slot Burner*Flame Temperature and Fuel Mixtures*Flame Structure*Nebulizers*Pneumatic*Ultrasonic

9.3 Hollow Cathode Lamps*Labtraining.com*

9.4 Line Broadening: Pressure*Doppler effect and broadening in AAS

9.5 Ionization Suppression*Interferences from Molecular Species*Background Correction*Continuum Source Correction (Link 2, 3, 4)*Zeeman Effect*Smith-Heiftje

9.6 Electrothermal*Graphite Furnace AAS*Schematic (Link 2, 3 see Figures 6.10-12)

9.7 Atomic Emission*ASDL*ICP-MS (Link 3)

9.8 Relative LOD for Flame AAS, AES, GFAAS, and ICP

9.9 Applications*Horiba*Analysis of carbon filters*Be in blood*Cholesterol via colloidal Au*Forensics (Link 1, 2, 3)

7. Introduction to Separations

10.1 Introduction Wikipedia - Library for Science* Michael Tswett * Martin and Synge work on LC and the 1952 Nobel Prize

10.2 Basic Terms: Column Chromatography * Stationary Phase, s.p. * Mobile Phase, m.p. * Partition Coefficient, K * Retention Time, t_r* Dead Time, t_m* Capacity Factor, k’* Relative Retention Factor (selectivity), α

10.3 Band Broadening * Plate Height, H = σ²/L * Longitudinal Diffusion, B/u * Mass Transfer Effects, Cu * Within the Stationary Phase, Cs * Within the Mobile Phase, Cm * Multiple Paths for Solute Flow, Eddy Diffusion A, German animation * The van Deemter Equation, H = A + B/u + Cu * Efficiency of Separation

10.4 Resolution, R_s (Link 2) * Plates, N = L/H * N and R_s * R_s α L^1/2

8. Gas Chromatography

11.1 GC Block Diagram

11.2 Basics: Injection Port * Split Injections * Carrier Gas * Column *Makeup Gas * Detectors

11.3 Columns: Packed vs. Capillary Columns (link 2, 3) * Van Deemter Equation Considerations * Effect of A – Single Path for Capillary Columns * B/u effects – Largest in the gas phase, fast u desirable * Cu effects – Thin s.p. * Types of GC stationary phases (Link 1) * Polar vs. Nonpolar * Temperature Programming * Example of a effects on a chromatogram, another link

11.4 Carrier Gases * Almost Always He * N₂ and H₂ are possible

11.5 Sample Injection (see page 3) Also Link 2. * Split Injections * Splitess * Solid Phase Microextraction (SPME)

11.6 Detectors for Gas Chromatography * Make-up Gas * Thermal Conductivity Detector (TCD) Link 2 * Flame Ionization Detector (FID) Link 2 * NPD * FPD * Electron Capture Detector (ECD) Link 2, Link 3 * Photoionization Detector (PID) Link 2 * FT-IR * Mass Spectrometers

11.7 Quantitative Analysis * Calibration Curve * Standard Addition * Method of Internal Standard (from Cal State – Fresno) *

11.8 GC troubleshooting guide for HP-GC's (now Agilent) * Capillary columns from Sigma-Aldrich * Chromtech

11.9 GC in Forensics * Controlled Substances Forensic Drug Identification by GC-IR * An example of explosives detection from the FBI * GC/MS screening for amphetamines from the DOJ * Los Alamos National Lab Forensics Science Center * Purge and Trap * Clinical Chemistry Application

9. Liquid Chromatography

12.1 AJP Martin and RLM Synge’s Original Paper on Liquid Chromatography, Synge’s Biography

12.2 HPLC Components * Liquid Mobile Phase * Pump * Injection Valve * Separation Column * Detector

12.3 Band Broadening in LC * Van Deemter Considerations, H = A + B/u + Cu * B/U effects – diffusion is 100x less in liquids when compared to gases * Cu effects largest in LC * Minimizing Cu effects requires smaller packing particles – Surface area/ Volume – High pressures * Effect of particle size on separation efficiency, see Figure 2, Link 2

12.4 HPLC Pumps * Pressures to 6000 psi + * Pulse free – prevents solute remixing * Control Flow Rates 0.1 to 10 mL/min * Reciprocating Pumps * Single Piston * Link 2 * Syringe Pump * Pulse Dampers * Coils * Diaphragms

12. 5 Sampling Valves, page 2

12.6 Pre-Column Filters + Analytical HPLC Columns (images) * Silica * Modified Silica, C-18, C-8, others * Reversed (polar m.p.-nonpolar s.p.) vs. Normal Phase (nonpolar m.p. – polar s.p.) Separations * Partition (modified silica) vs. Adsorption (unmodified silica) Chromatography * Column Care, Link 2

12. 7 Mobile Phases * Polar vs. non polar * Most Separations handled by C-18 s.p. and H₂O/MeOH or H₂O/CH₃CN m.p. * Isocratic (constant composition) vs. Gradient (variable composition) elutions * Column Heaters, improvement of Cu characteristics

12. 8 Detectors * Refractive Index (RI), page 2 * UV-vis Absorbance * Fixed Wavelength * Diode Array (2 pages) * Fluorescence * Conductivity (read all three pages) * FT-IR * Evaporative Light Scattering Detector (2 pages) * Electrochemical Detectors * Mass Spectrometry * HPLC-MS interface

12.9 UPLC Link 1

12.10 User’s Guide From University of Kentucky * HPLC troubleshooting guides Link 1, 2, 3, 4, 5, 6, A Google Search * An HPLC Simulator * GC and LC in Clinical Chemistry *

Interesting Analytes: Cocaine In Municipal Waters, Other Drugs of Abuse in Wastewaters, Hormones,

10. Capillary Electrophoresis (CE)

13.1 Electrophoresis vs. CE * Basic Block Diagram

13.2 Van Deemter Equation Considerations (H = A + B/u + Cu) * A = 0, as only one path is possible * Cu = 0, as there is no s.p. in CE * Theoretical Plates: HPLC – 2,000 to 10,000, CE – 50,000 to 500,000

13.3 Theory of Electrophoresis * Electrophoretic mobility * Electro-osmosis * t_r trends cations < neutrals < anions * flow velocity profiles, CE vs. HPLC

Theoretical Plates

13.4 Sample Injections * Pressure Injection * Electro-kinetic

13.5 Microfluidic Chips, See this video, link 2,

13.6 Detectors see Table 1 page 298A * Challenges * Narrow capillary/channels (20-75 μm) * UV-vis Absorbance * Fluorescence * Tagging agents (an example from Beckman) * CE-LIF

CE-arrays * Electrochemical * Mass Spec

13.7 Electrospray – 2002 Nobel Prize for John B. Fenn of Virginia Commonwealth University

13.8 Modified CE separations * Surfactant Modified, Anions < Neutrals < Cations * Micellar Electrokinetic Chromatography (1)

A Comparison of LC vs. MEC-CE

13.9 Analytical Chemistry Articles * 1989 Analytical Chemistry A-page article by AG Ewing * "How capillary electrophoresis sequenced the human genome.", N. J. Dovichi and J. Z. Zhang, Angew. Chem. Int. Ed., 39 4463 (2000). * Analytical Chemistry “How Analytical Chemists Saved the Human Genome Project…or at least gave it a helping hand” * A CE-LIF array from DOE’s Joint Genome Institute. * “Ultra-high-speed DNA fragment separations using microfabricated capillary array electrophoresis chips” AT Wooley, RA Mathies, Proc. Natl Acad Sci. 91, 1994 11348-11352 * Coupled with PCR Amplification * RA Mathies Group at UC Berkeley * N. Dovichi at Notre Dame * Sanger DNA Sequencing - Capillary Electrophoresis Animation * Thermo Fisher

11. Mass Spectrometry

14.1 Wikipedia * Basic Block Diagram

Sample Inlet à Ion Source* à Mass Analyzer* à Ion Transducer* à Signal Processing à Mass Spectrum

* indicates under vacuum conditions

14.2 Ion Sources * Electron Impact (Hard) Fragmentation * Chemical Ionization (Soft) MW information * Ionization of solid and nonvolatiles * Field Desorption * Fast Atom Bombardment * Matrix-Assisted Laser Desorption/Ionization (MALDI) * Direct Probe * Electrospray – 2002 Nobel Prize for John B. Fenn of Virginia Commonwealth University (video) * Atmospheric Pressure Chemical Ionization

14.3 Recent Developments in Ionization Techniques * Direct Analysis in Real Time (DART, Video) * Desorption Electrospray Ionization (DESI, Video) * Atmospheric Pressure Photoionization Source (APPI)

Desorption atmospheric pressure photoionization (DAPPI) * Summary from Aglient

14.4 Mass Analyzers * Resolution * Magnetic Sector (Video @3:45) * Double Focusing (Video) * Quadrapole, (video) * Time of Flight (video @48 sec) * Ion Trap (Video) * Orbitrap (A review publication) (Video) * MS-MS systems * Quad-Quad (Triple Quad) * QTOF (Pubmed) * Electron Multiplier

14.5 ICP-MS * Agilent ICP-MS diagram

14.6 Guides to MS * I-mass guides * Spectroscopy Now * ASMS * Ion Sources

12. Electrochemistry

12.1 Review * Daniell Cell * Video * The Nernst Equation

12.2 Standard Electrode Potentials * Electrochemical Series (Link 2)

12.3 Connection between E_cell, ∆G, and K

12.4 Single Electrode Potentials, Precipitation Reactions on Electrodes

12.5 Significant Figures and pH.

12.6 Reference Electrodes (SHE, SCE, Ag/AgCl)

13. Potentiometric Membrane Electrodes

13.1 Ion Selective Electrodes From Warsaw University of Technology

13.2 Beginner’s Guide From Nico2000 Glass pH Electrode

13.3 Latest Review Literature on ISE's from Google Scholar

14. Voltammetry

14.1 Analytical Electrochemistry *ASDL

14.2 Chronoamperometry * Chronoamperometric Glucose Sensor * Link 2.

14.3 Cyclic Voltammetry: J. Chem Ed. 2018,95,197* CV in Libretext

*CV in J.Chem.Ed Sept. 1983 * Detection of Dopamine in the Brain, Anal. Chem. 60, 769A, 1988

15. Special Topics. X-Ray Photoelectron Spectroscopy, Atomic Forces Spectroscopy.

Exam Dates for Spring 2023

· Exam 1 (100 points), Friday, February 10

· Exam 2 (100 points), Wednesday, March 8

· Exam 3 (100 points), Wednesday, April 26

· Final Exam Tuesday, May 9, 10:15 (150 points) (UI Registrar)

· Laboratory (150 points)

Class Averages on American Chemical Society Instrumental Analysis Exams

Year- National Percentile Avg, 2021-61^st, 2018- 69^th, 2011-82^nd, 2010-63^rd, 2009-74^th, 2008-66^th, 2007-69^th, 2006-60^th, 2005-74^th, 2003-86^th, 2002-86^th

Old Exam Files – Please note that the exams from previous years may not correspond to this year's course materials or exam subject matter. They can provide you with an idea as to the exam format and additional homework assignments.

1998, 1999, 2000, 2002, 2005, 2006, 2007,2008, 2009 , 2010, 2011