GenChem
Week 12
Patient Project: Ion Selective
Electrodes
Today’s Agenda:
 Review patient project.
Use an ISE to measure [Na+] & [Ca2+]
 Diagnose patient.
 Plan poster.
GenChem
Looking Ahead
13
14
15
16
17
21
22
23
24
Ion-selective electrodes
(12)
20
Lecture
Exam 4
Lab Final Exam (Practical)
(13)
27
28
29
Last Makeup
Lab
30
Patient Project Poster
Presentation
(14)
Final Exam: Monday, May 11, 10:30
1
GenChem
Instructor & Course Evaluation
We are using the University’s Teacher &
Course Evaluation (TCE) Online course
evaluation tool.
A. You will receive (or may already have)
an email from TCE with the URL
when the evaluation is available.
B. You will have about two weeks to
respond. The site will be closed and
data downloaded on Sunday, April
26th.
GenChem
Poster Presentation
Things you need to know
 The poster presentation will be in-class on April 27th &
28th.
Your poster will be graded on the spot. The grading
rubric is posted to the syllabus. All group members must
be present for the grading unless excused by the TA.
 You are required to evaluate two peer posters. Form
available from D2L content section.
GenChem
Practical Final Exam
The Problem
Clinical researchers are
investigating the effects of a new
drug designed to lower blood
glucose levels in diabetic patients
They have blood and urine samples
taken from lab rats to whom the
drug has been administered.
These need to be tested and
compared to the “before” results.
A Study Guide is posted to D2L.
The Patient Project
GenChem
 Patient case studies
 Patient interview data
 Urine analysis (test strips)
 CK and LD tests
 Glucose tests
 Ion-selective electrodes
 Diagnosis and presentation as a poster
GenChem
Testing for sodium & calcium:
ion-selective electrodes.
An
example of
sensor
technology.
GenChem
What is an ion selective
electrode?
• a device that generates an
electric potential proportional to a
particular ion’s concentration.
• a device for determining the
presence and/or concentration of
a particular ion.
GenChem
Let′s think!
Potentiometric measurements
In your groups discuss
• What are the necessary characteristics of
an ISE?
• How is it able to “read” concentrations?
E cell
 0.0591 V 
C
 log [ion]
z


The Nernst Equation
GenChem
Reading a potentiometric graph.
Potentiometric measurements
Potentiometric measurements
200
250
What
happened
here?
mV
mV
150
150
100
50
0,00E+00 2,00E-02 4,00E-02 6,00E-02
8,00E-02 1,00E-01
2+
[Ca ]
50
0
1
2
3
4
- log [ion]
5
6
7
8
GenChem
Ion selective
Electrode
Pre-lab
Let′s think!
GenChem
Preparing a Primary Standard
In your groups review your responses to the following
pre-lab question and come up with a consensus
answer.
Write a procedure for preparing a 0.500 M standard
solution from solid sodium chloride, NaCl. This procedure
must include answers to the following questions
 how much of the solution should be made?
 what glassware should be used to measure the
volumes?
Let′s think!
GenChem
Preparing another Standard
In your groups review your responses to the following
pre-lab question and come up with a consensus
answer.
The guide recommends standards to prepare. Describe in
detail how you would go about making the 0.0500 M
sodium standard solution.
GenChem
Let′s think!
Expected Outcome
In your groups review your responses to the
following pre-lab question and come up with a
consensus answer.
Consider the standard solutions recommended by the
guide for the calcium assay. Between which standards
do you expect a sample containing a normal calcium
level to fall?
Explain why you made that choice.
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
Solutions on your bench
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Sodium ISA in a small beaker
0.5M Sodium Standard
Roughly 100 mL in a small beaker
0.5M Sodium Standard in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Solutions on your bench
Sodium ISA in a small beaker
0.5M Sodium Standard
Roughly 100 mL in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
0.5M Sodium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.5M Sodium Standard
+
45.00 mL Nanopure H2O
0.05M Sodium soln
25.00 mL 0.5M Sodium Standard
+
25.00 mL Nanopure H2O
0.25M Sodium soln
Exactly 50.00 mL
0.5M Sodium
Standard in a small
beaker
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Solutions on your bench
Sodium ISA in a small beaker
0.5M Sodium Standard
Roughly 100 mL in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
0.5M Sodium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.5M Sodium Standard
+
45.00 mL Nanopure H2O
0.05M Sodium soln
25.00 mL 0.5M Sodium Standard
+
25.00 mL Nanopure H2O
0.25M Sodium soln
DO THIS THIRD
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.05M Sodium soln
+
45.00 mL Nanopure H2O
0.005M Sodium soln
5.00 mL 0.25M Sodium soln
+
45.00 mL Nanopure H2O
0.025M Sodium soln
Exactly 50.00 mL
0.5M Sodium
Standard in a small
beaker
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Solutions on your bench
Sodium ISA in a small beaker
GenChem
0.5M Sodium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
Exactly 50.00 mL in a small beaker
0.5M Sodium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.5M Sodium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.5M Sodium Standard
+
25.00 mL Nanopure H2O
0.05M Sodium soln
0.25M Sodium soln
Exactly 50.00 mL
0.5M Sodium
Standard in a small
beaker
DO THIS THIRD
5.00 mL 0.05M Sodium soln
+
45.00 mL Nanopure H2O
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with Buffer
added
5.00 mL 0.25M Sodium soln
+
45.00 mL Nanopure H2O
0.005M Sodium soln
Add exactly 1.00
mL pH 10 Buffer
0.005M Na+
Add exactly 1.00
mL pH 10 Buffer
0.025M Na+
Add exactly
1.00 mL pH
10 Buffer
0.025M Sodium soln
Add exactly 0.90
mL pH 10 Buffer
0.05M Na+
Add exactly
1.00 mL pH
10 Buffer
Add exactly 0.90
mL pH 10 Buffer
0.25M Na+
0.5M Na+
“XX”
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Solutions on your bench
GenChem
0.5M Sodium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
Sodium ISA in a small beaker
Exactly 50.00 mL in a small beaker
0.5M Sodium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.5M Sodium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.5M Sodium Standard
+
25.00 mL Nanopure H2O
0.05M Sodium soln
0.25M Sodium soln
Exactly 50.00 mL
0.5M Sodium
Standard in a small
beaker
DO THIS THIRD
5.00 mL 0.05M Sodium soln
+
45.00 mL Nanopure H2O
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with Buffer
added
5.00 mL 0.25M Sodium soln
+
45.00 mL Nanopure H2O
0.005M Sodium soln
Add exactly 1.00
mL pH 10 Buffer
0.005M Na+
Add exactly 1.00
mL pH 10 Buffer
0.025M Na+
Add exactly
1.00 mL pH
10 Buffer
0.025M Sodium soln
Add exactly 0.90
mL pH 10 Buffer
0.05M Na+
Add exactly
1.00 mL pH
10 Buffer
Add exactly 0.90
mL pH 10 Buffer
0.25M Na+
0.5M Na+
“XX”
DO THIS FIFTH
IMPORTANT! Configure
(set-up) for mV before
taking readings!
IMPORTANT! Allow probe
to equilibrate for 1-2
minutes for each reading!
Potential (mV)
readings with
Logger Pro
Start with the most dilute (0.005M) solution and work stepwise towards the most concentrated (0.5M)
Read 0.005M Na+
Read 0.025M Na+
Read 0.05M Na+
Read 0.25M Na+
Read “XX”
Read 0.5M Na+
IMPORTANT! Patient
Sample “XX” must be read
at the same time as the
calibration dilutions!
Serum SODIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
DO THIS FIRST
4M NH4Cl/ 4M NH4OH (Sodium ISA)
Roughly 15 mL pH 10 Buffer
Solutions on your bench
GenChem
0.5M Sodium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
Sodium ISA in a small beaker
Exactly 50.00 mL in a small beaker
0.5M Sodium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.5M Sodium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.5M Sodium Standard
+
25.00 mL Nanopure H2O
0.05M Sodium soln
0.25M Sodium soln
Exactly 50.00 mL
0.5M Sodium
Standard in a small
beaker
DO THIS THIRD
5.00 mL 0.05M Sodium soln
+
45.00 mL Nanopure H2O
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with Buffer
added
5.00 mL 0.25M Sodium soln
+
45.00 mL Nanopure H2O
0.005M Sodium soln
Add exactly 1.00
mL pH 10 Buffer
0.005M Na+
Add exactly 1.00
mL pH 10 Buffer
0.025M Na+
Add exactly
1.00 mL pH
10 Buffer
0.025M Sodium soln
Add exactly 0.90
mL pH 10 Buffer
Add exactly
1.00 mL pH
10 Buffer
Add exactly 0.90
mL pH 10 Buffer
0.05M Na+
0.25M Na+
“XX”
0.5M Na+
DO THIS FIFTH
IMPORTANT! Configure
(set-up) for mV before
taking readings!
IMPORTANT! Allow probe
to equilibrate for 1-2
minutes for each reading!
Potential (mV)
readings with
Logger Pro
Start with the most dilute (0.005M) solution and work stepwise towards the most concentrated (0.5M)
Read 0.005M Na+
Read 0.025M Na+
Read 0.05M Na+
Read 0.25M Na+
Read “XX”
Read 0.5M Na+
IMPORTANT! Patient
Sample “XX” must be read
at the same time as the
calibration dilutions!
DO THIS SIXTH
DO THIS LAST
Potential vs. Concentration calibration
plot with Logger Pro or Excel
“0.005M ” to “0.5M” readings are used to construct the
calibration plot (Potential vs. Concentration)
Patient “XX”’s sodium
ion concentration
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
4M KCl in a small beaker
0.03M Calcium Standard
Roughly 100 mL in a small beaker
0.03M Calcium Standard in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
4M KCl in a small beaker
0.03M Calcium Standard
Roughly 100 mL in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
0.03M Calcium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.03M Calcium Standard
+
45.00 mL Nanopure H2O
0.003M Ca2+ soln
25.00 mL 0.03M Calcium Standard
+
25.00 mL Nanopure H2O
0.015M Ca2+ soln
Exactly 50.00 mL
0.03M Calcium
Standard in a small
beaker
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
4M KCl in a small beaker
0.03M Calcium Standard
Roughly 100 mL in a small beaker
GenChem
Patient Sample XX
Exactly 50.00 mL in a small beaker
0.03M Calcium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.03M Calcium Standard
+
45.00 mL Nanopure H2O
0.003M Ca2+ soln
25.00 mL 0.03M Calcium Standard
+
25.00 mL Nanopure H2O
0.015M Ca2+ soln
DO THIS THIRD
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.003M Ca2+ soln
+
45.00 mL Nanopure H2O
0.0003M Ca2+ soln
5.00 mL 0.015M Ca2+ soln
+
45.00 mL Nanopure H2O
0.0015M Ca2+ soln
Exactly 50.00 mL
0.03M Calcium
Standard in a small
beaker
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
GenChem
0.03M Calcium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
4M KCl in a small beaker
Exactly 50.00 mL in a small beaker
0.03M Calcium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.03M Calcium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.03M Calcium Standard
+
25.00 mL Nanopure H2O
0.003M Ca2+ soln
0.015M Ca2+ soln
Exactly 50.00 mL
0.03M Calcium
Standard in a small
beaker
DO THIS THIRD
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with KCl
added
5.00 mL 0.003M Ca2+ soln
+
45.00 mL Nanopure H2O
5.00 mL 0.015M Ca2+ soln
+
45.00 mL Nanopure H2O
0.0003M Ca2+ soln
Add exactly 1.00
mL 4M KCl
0.0003M Ca2+
Add exactly 1.00
mL 4M KCl
0.0015M Ca2+
0.0015M Ca2+ soln
Add exactly 0.90
mL 4M KCl
0.003M Ca2+
Add exactly 1.00
mL 4M KCl
Add exactly 1.00
mL 4M KCl
Add exactly 0.90
mL 4M KCl
0.015M Ca2+
0.03M Ca2+
“XX”
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
GenChem
0.03M Calcium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
4M KCl in a small beaker
Exactly 50.00 mL in a small beaker
0.03M Calcium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.03M Calcium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.03M Calcium Standard
+
25.00 mL Nanopure H2O
0.003M Ca2+ soln
0.015M Ca2+ soln
Exactly 50.00 mL
0.03M Calcium
Standard in a small
beaker
DO THIS THIRD
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with KCl
added
5.00 mL 0.003M Ca2+ soln
+
45.00 mL Nanopure H2O
5.00 mL 0.015M Ca2+ soln
+
45.00 mL Nanopure H2O
0.0003M Ca2+ soln
Add exactly 1.00
mL 4M KCl
0.0003M Ca2+
0.0015M Ca2+ soln
Add exactly 1.00
mL 4M KCl
0.0015M Ca2+
Add exactly 0.90
mL 4M KCl
0.003M Ca2+
Add exactly 1.00
mL 4M KCl
Add exactly 1.00
mL 4M KCl
Add exactly 0.90
mL 4M KCl
0.015M Ca2+
0.03M Ca2+
“XX”
DO THIS FIFTH
IMPORTANT! Configure
(set-up) for mV before
taking readings!
IMPORTANT! Allow probe
to equilibrate for 1-2
minutes for each reading!
Potential (mV)
readings with
Logger Pro
Start with the most dilute (0.0003M) solution and work stepwise towards the most concentrated (0.03M)
Read 0.0003M Ca2+
Read 0.0015M Ca2+
Read 0.003M Ca2+
Read 0.015M Ca2+
Read “XX”
Read 0.03M Ca2+
IMPORTANT! Patient
Sample “XX” must be read
at the same time as the
calibration dilutions!
Serum CALCIUM Determination Flowchart (per 4 students), CHEM 102 Spring 2011
Solutions in the fume hood
4M KCL Calcium Ionic Strength Adjuster
DO THIS FIRST
Roughly 15 mL 4M KCl
Solutions on your bench
GenChem
0.03M Calcium Standard
Patient Sample XX
Roughly 100 mL in a small beaker
4M KCl in a small beaker
Exactly 50.00 mL in a small beaker
0.03M Calcium Standard in a small beaker
Exactly 50.00 mL of
Patient Sample XX in
small beaker
DO THIS SECOND
Parallel dilutions
(perform in 50.00 mL
volumetric flasks)
5.00 mL 0.03M Calcium Standard
+
45.00 mL Nanopure H2O
25.00 mL 0.03M Calcium Standard
+
25.00 mL Nanopure H2O
0.003M Ca2+ soln
0.015M Ca2+ soln
Exactly 50.00 mL
0.03M Calcium
Standard in a small
beaker
DO THIS THIRD
Serial dilutions
(perform in 50.00 mL
volumetric flasks)
DO THIS FORTH
Solutions
with KCl
added
5.00 mL 0.003M Ca2+ soln
+
45.00 mL Nanopure H2O
5.00 mL 0.015M Ca2+ soln
+
45.00 mL Nanopure H2O
0.0003M Ca2+ soln
Add exactly 1.00
mL 4M KCl
0.0003M Ca2+
0.0015M Ca2+ soln
Add exactly 1.00
mL 4M KCl
0.0015M Ca2+
Add exactly 0.90
mL 4M KCl
Add exactly 1.00
mL 4M KCl
Add exactly 1.00
mL 4M KCl
Add exactly 0.90
mL 4M KCl
0.003M Ca2+
0.015M Ca2+
“XX”
0.03M Ca2+
DO THIS FIFTH
IMPORTANT! Configure
(set-up) for mV before
taking readings!
IMPORTANT! Allow probe
to equilibrate for 1-2
minutes for each reading!
Potential (mV)
readings with
Logger Pro
Start with the most dilute (0.0003M) solution and work stepwise towards the most concentrated (0.03M)
Read 0.0003M Ca2+
Read 0.0015M Ca2+
Read 0.003M Ca2+
Read 0.015M Ca2+
Read “XX”
Read 0.03M Ca2+
IMPORTANT! Patient
Sample “XX” must be read
at the same time as the
calibration dilutions!
DO THIS SIXTH
DO THIS LAST
Potential vs. Concentration calibration
plot with Logger Pro or Excel
“0.0003M ” to “0.03M” readings are used to construct the
calibration plot (Potential vs. Concentration)
Patient “XX”’s calcium
ion concentration
GenChem
Performing the analysis safely.
Don’t forget to wear gloves
Performing the analysis reliably.
 For your sodium standards, use ONLY the
NANOpure Water for your dilutions
 Volumetric glassware is available for your use.
GenChem
Two different
kinds of
electrodes
The Calcium ISEs are made
by our preproom team.
The Sodium ISEs are
purchased from a vendor.
Do you have these instructions? Both are plugged into the
They’re in D2L – content –
computers and managed
Logger Pro Guides – NaCa ISE
by the Logger Pro
software
Instructions
GenChem
Sodium ISE Special Need
The “Distilled Water”
contains enough sodium ion
to invalidate your
measurements with the
electrode. For this reason
you MUST use
NANOPURE water for all
your sodium ion solution
preparations.
GenChem
Let′s explore!
Your Challenge
Prepare your standards
Measure your samples
Available resources:
 solid NaCl and CaCl2 .
 ionic strength adjustors
Implement your
experimental procedure!
 NANOpure water
 volumetric glassware
 Ion-selective electrodes
You have
90 minutes
Progress Report
You will now complete
and submit the
progress report
covering this week and
last.
GenChem
These are to be individual efforts although
consultation is highly encouraged.
Identification: name, TA name, group members
and patient identification.
Glucose standards. List of standards prepared,
sample calculations and description of how
solutions were prepared.
Glucose calibration plot
[glucose] found in patient samples, comparison to
normal levels and diagnostic conclusions.
Sodium and Calcium calibration plots
Description of standard solutions prepared
including all calculations
[Na+] and [Ca2+] values found in patient samples,
comparison to normal levels and diagnostic
conclusions.
GenChem
Group
Meeting
As a group review your results for all three weeks.
 decide on a diagnosis for your patient.
 plan your slide show.
 assign tasks.