Talk dirty to me:
Teaching undergraduate students
the importance of good hygiene in
the teaching laboratory
Luke Gallion, Dr. Michael Samide,
Dr. Anne Wilson
Butler University, Department of Chemistry
Indianapolis, IN
1
Presentation Outline
•  Significance of teaching undergraduates
the importance of a clean lab
•  Previous work/current practices
•  Butler University’s current laboratory
sequence
•  Modified laboratory sequence
•  Effects of the modified laboratory
2
http://searchpp.com/messy-laboratory/
3
Significance
•  Cleanliness and its
safety impacts lead to
success in the
laboratory
•  “Maintain proper PPE”
and “accident
avoidance” ranked two
highest safety priorities
by industrial chemists
Fair, J. D.; Kleist, E. M.; Stoy, D. M. J. Chem.
Educ. 2014, ASAP. DOI: 10.1021/ed400570f.
http://www.amazon.com/Simpsons-ChemicalSafety-Poster-Procedures/dp/B00BR0B9VG
4
Previous Work –
University of Kentucky
•  Safety guidelines are comprehensive but discuss
what to do after an incident, not how to prevent
Safety in the Analytical Laboratory: Guidelines and Practices.
www.chem.uky.edu/courses/che226/003-Safety_Guide.pdf (accessed November 25, 2014).
5
Previous Work –
Iowa State University
•  Great for cataloging
safety issues
•  Can be boring and
dry
•  Only reading it
Miller, G. J.; Heideman, S. A.; Greenbowe, T. J. J. Chem. Educ. 2000, 77, 1185-1187.
6
Previous Work –
Seattle University
•  Held a safety training session
–  Alternate class discussion and worksheets
–  Students more engaged by breaking up
discussion and worksheets
•  Safety teams
•  Weekly pre-lab safety presentations
Alaimo, Peter J.; Langenhan, Joseph M.; Tanner, Martha J. J. Chem. Educ.
2010, 87, 856-861.
7
Our Current Lab Sequence –
Butler University
•  Week 1: Check in, fermentation (aqueous sugar and
yeast) set-up
–  20 minutes
•  Week 2: Filter solution, perform fractional distillation on
filtrate
–  3 hours
•  Week 3: Identification of unknown compound using
melting point, TLC, and mass spectrometry
–  2 hours
Azman, A. M.; Barrett, J. A.; Darragh, M.; Esteb, J. J.; McNulty, L. M.; Morgan, P.
M.; O’Reilly, S. A.; Wilson, A. M. J. Chem. Educ. 2013, 90, 140-141.
8
Modification
•  Week 1: Check in, fermentation (aqueous sugar and
yeast) set-up
–  Pour TLC plates
–  Evaluate cleanliness of laboratory
–  2.5 hours
•  Week 2: Filter solution, perform fractional distillation
on filtrate
–  3 hours
•  Week 3: Identification of unknown compound using
melting point, TLC, and mass spectrometry
–  Compare commercially-available TLC plate to handpoured TLC plate
–  2.5 hours
9
Procedure for Student-Poured
Plates
•  1.2 g silica
•  0.1 g CaSO4
•  Fluorescence
indicator green 254
nm
•  2.7 mL H2O
10
Qualitative Results – Week 1
11
Qualitative Results – Week 1
12
Qualitative Results – Week 1
13
Qualitative Results – Week 1
14
Qualitative Results – Week 1
15
Qualitative Results – Week 1
16
Qualitative Results
•  “It was helpful to see how the plates are made/work.
However the homemade plates were a lot more difficult
to use and I didn’t get any date for one of my
compounds.”
•  “Homemade TLC plates, in my opinion, don’t work as
well as pre-made TLC plates”
•  “Home-made plates are extremely fragile and therefore
not reliable as some completely fell apart. Stick with the
purchased commercial plates.”
•  “The TLC plate I made fell apart when I placed it inside
the beaker to run.”
17
Qualitative Results
“Luke is cute”
18
Quantitative Results
Mean scores
1= “Not Clean,” “No impact,” “Not worthwhile”;
6= “Very Clean,” Strong Impact,” “Very Worthwhile” Survey Statements for
Response Students That
Performed Modified
Laboratory Control Group
Students p Values
(Significance) How would you have rated
your lab cleanliness before
this laboratory? 4.45 ± 1.15 4.93 ± 1.03 0.0817,
significant Indicate how this laboratory
affected your view on lab
cleanliness. 4.42 ± 1.36 3.47 ± 1.55 0.0266,
significant Now that you know how a
TLC plate is prepared, how
worthwhile is it to purchase
commercial plates? 5.19 ± 1.07 3.60 ± 1.68 0.0016,
significant 19
Quantitative Results
Correct Response, % Survey Question Students That
Performed Modified
Laboratory Control Group p Values
(significance) Rf Calculation 93.5 80.0 0.0869, significant Rf understanding 80.6 73.3 0.2925, not significant Polarity/IM forces 71.0 33.3 0.0072, significant 20
Summary/Conclusions
•  Greater appreciation of lab cleanliness in
hoods and common areas
•  Greater realization of the importance of
PPE
•  Greater understanding of TLC
•  Greater appreciation of common
laboratory techniques
21
Acknowledgements
• 
• 
• 
• 
• 
• 
Butler University Department of Chemistry
Professor Kelsie Graham
Dr. Michael Samide
Dr. Anne Wilson
ACS National Meeting & Exposition
You!
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References
1.  Banholzer, W. F.; Calabrese, G. S.; Confalone, P. Chem.
Eng. News 2013, 91 (18), 2.
2.  Laboratory Safety. http://www.acs.org/content/dam/acsorg/
about/governance/committees/training/acsapproved/
degreeprogram/laboratory-safety.pdf (accessed November
19, 2014).
3.  Fair, J. D.; Kleist, E. M.; Stoy, D. M. J. Chem. Educ. 2014,
ASAP. DOI: 10.1021/ed400570f.
4.  Alaimo, Peter J.; Langenhan, Joseph M.; Tanner, Martha J. J.
Chem. Educ. 2010, 87, 856-861.
5.  Miller, G. J.; Heideman, S. A.; Greenbowe, T. J. J. Chem.
Educ. 2000, 77, 1185-1187.
6.  Hill Jr., R. H.; Nelson, D. A.. Chem. Health Safety, 2005,
November-December, 19-23.
23
References
7.  Laboratory Health and Safety Training. https://www.amherst.edu/media/
view/64011/original/Laboratory%2BHealth%2Band%2BSafety
%2BTraining.doc (accessed November 19, 2004).
8.  The Chemical Safety Mechanism; Laboratory Housekeeping. http://
www.ehs.wisc.edu/chem/LaboratoryHousekeeping.pdf (accessed
November 19, 2014).
9.  Safety Policies – College of Life Sciences. http://lifesciences.byu.edu/
safety/LabSafety/SafetyPolicies.aspx (accessed August 22, 2014).
10.  Safety in the Analytical Laboratory: Guidelines and Practices.
www.chem.uky.edu/courses/che226/003-Safety_Guide.pdf (accessed
November 25, 2014).
11.  Miller, G. J.; Heideman, S. A.; Greenbowe, T. J. J. Chem. Educ. 2000, 77,
1185-1187.
12.  Azman, A. M.; Barrett, J. A.; Darragh, M.; Esteb, J. J.; McNulty, L. M.;
Morgan, P. M.; O’Reilly, S. A.; Wilson, A. M. J. Chem. Educ. 2013, 90,
140-141.
24
Fluorescent Green Indicator
•  Zinc silicate, Mn doped
•  Zn2SiO4
•  http://www.sigmaaldrich.com/catalog/
product/fluka/02554?lang=en&region=US
25
Previous Work
Hill Jr., R. H.; Nelson, D. A.. Chem. Health
Safety, 2005, November-December, 19-23.
26
Previous Work –
Iowa State University
Miller, G. J.; Heideman, S. A.; Greenbowe, T. J. J. Chem. Educ. 2000, 77, 1185-1187.
27
Quantitative Results –
Appreciation of laboratory
cleanliness
•  How would you have rated your lab cleanliness
before this laboratory?1 = “Not clean” 6 = “Very Clean”
•  Control Group (n=18): 4.93 ± 1.03
•  Students that Performed Modified Laboratory
(n=33): 4.45 ± 1.15
•  p Value: 0.0817
•  Statistically significant at 90% confidence level
28
Quantitative Results –
Appreciation of laboratory
cleanliness
•  Indicate how this laboratory affected your view
on lab cleanliness.
•  1 = “No impact”
6 = “Strong Impact”
•  Control Group (n=18): 3.47 ± 1.55
•  Students that Performed Modified Laboratory
(n=33): 4.42 ± 1.36
•  p Value: 0.0266
•  Statistically significant at 90% confidence level
29
Quantitative Results –
Appreciation of common laboratory
techniques
•  Now that you know how to prepare a TLC plate,
how worthwhile is it to purchase commercial
plates?
•  1 = “Not worthwhile” 6 = “Very Worthwhile”
•  Control Group (n=18): 3.60 ± 1.68
•  Students that Performed Modified Laboratory
(n=33): 5.19 ± 1.07
•  p Value: 0.0016
•  Statistically significant at 90% confidence level
30
Quantitative Results
A student ran a TLC of an unknown compound on a
commercial silica gel plate. The distance to the
solvent front was 5.0 cm. The unknown compound
being analyzed had an Rf of 0.4. How far did the
compound travel up the plate?
•  Control Group (n=18): 80% correct
•  Students that Performed Modified Laboratory
(n=33): 93.5% correct
•  p Value: 0.0869
•  Statistically significant at 90% confidence level
31
Quantitative Results
The student from the previous question (#4) wanted
to replicate data. This time, the compound traveled
1.6 cm. What was the distance to the solvent front?
•  Control Group (n=18): 73.3% correct
•  Students that Performed Modified Laboratory
(n=33): 80.6% correct
•  p Value: 0.2925
•  Not statistically significant at 90% confidence level
32
Quantitative Results
Compound A is very polar. Compound B is nonpolar.
Compound C is of moderate polarity. If these three
compounds were spotted on a TLC plate and a mobile
phase of 90:10 hexanes: ethyl acetate was used, what
would be the elution order of the compounds from lowest
Rf value to highest Rf value be?
•  Control Group (n=18): 33.3% correct
•  Students that Performed Modified Laboratory (n=33):
71.0% correct
•  p Value: 0.0072
•  Statistically significant at 90% confidence level
33