Transcript Instrumental Methods of Analysis 1. Introduction 1. Writing Intensive 1. Rewrites are Required 2.

Instrumental Methods of Analysis
1. Introduction
1. Writing Intensive
1. Rewrites are Required
2. Large Amount of Excel Data Management
2. Work
1. Individual
1. Work Log
2. Own Sample
3. Exams
4. Lab Book pages
2. Group
1. Division and Attribution of Labor (Accountability)
2. Reports
3. Calibration Curves
3. Single Analyte (Skill Development and Cross Comparison Methods)
1. Overlapping Themes
1. Statistics/Sampling
2. Solution Chemistry
3. EDTA
4. Isotopes
5. Phase Separations
Instrumental Methods of Analysis
1. Introduction
1.
2.
3.
4.
Writing Intensive
Work
Single Analyte
Problem Based
• What is best method for lead analysis?
• What is best method for This particular sample?
5. Ethics and Service Learning
1. How do we know?
2. Critical Thinking
Electronics, Spectroscopy,
Electrochemistry, Chromatography
Confusion
Confusion
“Too much from instructor” information
7 different analytes
7 different methods
Chromium &
permanganate
UV-Vis
Iodide
Electrolysis
Methanol Gas
Chromatography
Fluoride
Ion Selective
Electrode
Cu Graphite
Furnace
Atomic
Absorption
How do we select
Or compare methods/
Instruments?
Quinine
Fluorescence
DMSO
Infrared
Spectroscopy
Choose Method:
Cross Compare/measure LOD
Figures of Merit Theme
Pb Limit of detection?
Pb Linear range?
Pb Selectivity?
Pb Signal/Noise?
Calcein Blue
Pb Fluorescence
Quenching
Pb Anodic
Stripping
Voltammetry
Knowledge
Role of solution pH important
Pb Dithizone
UV-Vis
Pb Atomic
Absorption
207Pb
in EDTA by
proton NMR
Tetraethyl 207Pb MS
Pb Ion Selective
Electrode
EDTA Pb HPLC
Pb EDTA Infrared
Spectroscopy
Week
“Lab”
Topic
Concept
Stat
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Chem Isotope Ethics
Pb & Society; Statistics and Ethics
Pototo populations
Signals & Noise; LOD
Analog & Digital filters x
Relevant Chemistry; Exam I
ISE & Pb(OH)2
x
Intro Spectroscopy
IR & UV-Vis
x
Molecular Spectroscopy
IR & UV-Vis
x
Fluorescence and AA
Fluorescence and FAA x
x
AA and Vibrational, Exam II
Fluorescence and FAA x
x
Break, NMR
Break
NMR, Off campus sampling
NMR, ASV
x
x
x
MS,
NMR, ASV
x
x
x
Intro Electrochem., Select Method
sample prep
x
x
x
x
x
Potentiometry,
sample analysis x
x
ASV, Take home exam III
ICP-MS, GC
x
x
Separations
ICP-MS, GC
x
x
Separations
How do we know? Ethics x
x
Why Lead?
Health
Same size,
Shape, chemistry
Different
Orbitals,
Different total
Number of electrons
Warren et al, TIBS, 1998, 23, 217
Current
measurements
no longer
rely on zinc
protoporphyrin
as PbB effects
on fetal development
can be detected
at values of PbB
<5 ug/dL
An estimated 40% of lead in blood plasma bound to ALAD
Wetmur, 1994
ALAD dehydratase with lead binding site
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
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
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)
Why Lead?
Everywhere
Lead as an
ore in the earth
relatively
benign
Human activity
distributes
lead into the
environment
Modern major uses
1. Pigments
2. Leaded Gasoline
3. Munitions
Eliminating Childhood Lead Poisoning:
A Federal Strategy Targeting Lead Pain Hazards, Feb. 2000
Decade
Thousand
Tons
white lead
Thousand
Tons
red lead
(litharge)
Millions
Occupied
Units
White lead
per unit
(pounds)
Remaining
lead
thousands
tons
1914-23
1340
0
24.35
110
413
1920-29
1307
356
29.91
87
184
1930-39
737
421
34.86
42
104
1940-49
476
1189
42.83
22
72
1950-59
196
816
43.02
7
37
1960-69
82
781
63.45
3
20
1970-79
29
625
80.39
1
841
Other Ecosytem Impacts of Lead
To air
Mine
Deposit
locally
incinerate
ash
reclaim
Deposit
elsewhere
Fishing sinkers
& shot
Sewage
sludge
Cement block
landfill
Flow to groundwater
fertilizer
Plant uptake
Bottom sludge
groundwater
2009 Class Project
Growing Scientists
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
F 1996
National
Award for Uptown 5th graders sample and tour
The Class labs
F 1997
House Dust
Little village Boys and Girls Club
(failed) Northwest Incinerator
F 1998
Tight grid and isotopes
Bethel New Life: Brownfield
Soil sampling
F. 1999
Orozco School: House Dust
F 2000
ACS Pullman: White Lead Factory F 2001
Mtg
House Dust
F 2002
poster
West Pullman White Lead factory
S 2008
Lead in Toys
Evanston Childcare
Alanah Fitch [email protected]
Lead Elimination Action Drive
West-side Alliance for a Safe Environment (WASTE)
Center for Neighborhood Technology
Austin Neighborhood Council
Homes
Pb?
Municipal Waste Incinerator
Incinerator 1994, 1995, 1998
Wind
Background
Soil lead
“Shadow” depends on
Stack height
Decreasing amts
Largest deposition
Is here
Incinerator 1994, 1995, 1998
Control
sampling
Students meet with
elderly ladies who let
them sample soils.
The ladies discuss their
concerns.
Incinerator 1994, 1995, 1998
Soil Lead in parts per million (ppm)
Front
1040
187
440
4822 W. Potomac
4915 W. Kamerling
4833 W. Crystal
Back
1800
1850
1431
231
1385
250
150
372
garage
Incinerator 1994, 1995, 1998
Comparison homes, 17 mile away
1133
2808
2620
3067
2900
1538
700
6613 N. Ashland
BRICK
439
6729 N. Ashland
FRAME
Incinerator 1994, 1995, 1998
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
North
Wind Pattern
32
101
Class final: enter
Busch National Env.
Award competition –
Place third
23
12
346 546
15
Demolished lot
Cicero
320
644 m
Pulaski
1210 123
Chicago
Orr High
School
89 82
This data presented
To Mayor’s advisory
council
42
Washington
0
Incinerator 1994, 1995, 1998
14
12
> 0.5 mile from incinerator
8
6
< 0.5 mile from incinerator
4
2
0
0
10
0
20
0
30
0
40
0
50
0
60
0
70
0
80
0
90
0
10
50
11
50
12
50
13
50
Frequency
10
PPM Soil Lead
Incinerator 1994, 1995, 1998
Wind
Background
Soil lead
“Shadow” depends on
Stack height
Decreasing amts
Largest deposition
Is here
Incinerator 1994, 1995, 1998
Last time: we finally set up an experiment worthy of an
An air pollution expert
NE
NNE
N
ENE
61
46
E
30
15
0
-15
-30
-46
-61
0
15
30
46
61
SE
Incinerator 1994, 1995, 1998
Across
1
the system of pipes and other apparatus for conveying water,
liquid wastes, etc., as in a building
3.
the fluid that circulates and carries oxygen throughout the human
body
4.
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
10.
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
18.
a transparent, odorless, tasteless liquid, a compound of hydrogen
and oxygen, H20, that constitutes rain, oceans, lakes, rivers, etc.
19.
. 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
10.
a table illustrating the periodic system, in which the chemical
elements are shown in related groups
11.
. 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
2009 – Brainstorm on
Projects
Short list by next week
Health Effects of Lead
Inhalation depends upon
the particle size.
This data is for
humans
Dissolution of lead carbonate particles in
simulated gastric juices as a function of particle size
For birds, the uptake will depend upon the pH and grinding action in
the gizzard. For ruminants, the uptake will depend upon the lifetime
in the digestive organs
94-99% of lead attached to
external surfaces of
erythrocytes
1-6% lead in plasma,
of which 99% attached to
proteins
~0.1 to 0.6 % of lead is
as the free cation
Recognition will be similar for various species
Ca
Ba
Active
uptake of
calcium,
apparently
to lesser
extent other
divalent similar
sized cations,
including
lead.
Calcium uptake is controlled by Vitamin D and growth regulators
parathyroid hormone (PTH)
Calcium is stored to the endoplasmic reticulum, lead will also
go there
Basophilic Stippling of Dog Blood caused by nucleation of
ribonucleoproteins in presence of lead
High lead causes deformation of blood cells and shorter lifetime of
the red blood cell.
Double whammy - production is also affected
Current
measurements
no longer
rely on zinc
protoporphyrin
as PbB effects
on fetal development
can be detected
at values of PbB
<5 ug/dL
1 hour
after
exposure
lead is
found
within the
kidneys,
because
kidneys
are
monitoring
blood
calcium
levels via
the
Renal biopsy of a 28 year old shipwrecker. Dense
glomerular
intranuclear inclusion body is characterized by a fibrillary
filtration
outer margin; Cramer, Goyer et al. Brit. J. Indust. Med., 1984 rate
Renal biopsy of a 28 year old shipwrecker. Interstitial fibrosis
with atrophy of some tubular lining cells; Cramer, Goyer et al.
Brit. J. Indust. Med., 1984
Damage to kidney results in
hypertension
gout
Thomas Rowlandson’s The King’s Bath
Cruikshank’s gout
Calcium is closely monitored by kidney because it plays a large
role in various signalling processes
Calcium bound to calmodulin
C. Yang, G. S. Jas, K. Kuczera, J. Biomolecular Structural Dynamics,
2001, 19,257-271
Lead double whammy
1. Low lead turns on triggers
2. Hi lead turns off triggers
Calcium serves as a
trigger for muscle
contractions:
troponin C
Colic is a form of muscle spasming
So are the “shakes”
Lead, like calcium, is deposited to the hard tissues
Implications for the Trophic level of lead in the environment
Osteocalcin (bone Gla protein (BGP)) controls calcium deposition
and is affected by lead: weaker bones for affected individuals
Longitudinal Section & Cross Section of Bone
Trabecular
Bone
Compact Bone
Seizures can result from lead due to Ca triggers of the synapses
Other Irrelevant Information that
Is mildly amusing/interesting on Lead
~5,000 years ago
Cuppellation
Begins
886oC
-0.2oC (Au)
230oC (Ag)
Purity of Pb: 99.9% achieved