1. Analysis of Aerosols Produced From Pyrolysis of Natural Products
Chelsea Tyler- Chemistry Major
Sandra Spencer- Graduate Student Mentor
Gary Glish- Faculty Advisor
Good afternoon! My name is Chelsea Tyler and I am a Chemistry Major. I have been working on the analysis of aerosols produced from pyrolysis of natural products under the help and supervision of my graduate student Sandra Spencer and faculty advisor Gary Glish.

2. Objective
To analyze aerosols produced from pyrolysis of cellulose and lignin
Why is this important?
Environmental Impact
Alternative Fuels
Human Health Impact
The objective of this project is to analyze aerosols produced from pyrolysis of cellulose and lignin. Aerosols are solid and liquid particles suspended in a gas. They can occur naturally or be man made. The research of aerosols are important because they have an impact on our environment and ourselves. For example the bluish color seen at the Blue Ridge Mountains are a product of aerosols produced in the area. However, aerosols also have a negative environment impact when we think of Beijing, China and the thick fog they have over their cities which makes seeing very difficult. Aerosols are being studied for their environmental impact but also for others such as the subject of alternative fuels including the burning of biomass. Researchers have been interested in determining what is being produced from the burning of alternative fuels. Most importantly, aerosols impact human health. Inhalers and nasal sprays release aerosols that enter the body. Also cigarette smoking is one of the leading causes of preventable death in the United States. It is important to understand what aerosols do to our environment and our bodies. (REWRITE)

3. Components of Green Plants
Cellulose and Lignin
Natural polymers
Primary components of cell wall
Lignin
Our ultimate goal is to analyze cigarette smoke, but we most start basic. For that reason, I have been studying cellulose and lignin. Cellulose and Lignin are both natural polymers that are primary components of the cell wall in green plants. The molecular structure of Cellulose and Lignin is most important to me. This picture of cellulose is just one unit of a long chain. It is important to note that the molecular structures only contain Carbon, Hydrogen, and Oxygen.
Cellulose

4. What do we want to achieve?
Experimental Design
What do we want to achieve?
Real-time analysis
Structural Information
Range of compounds
Method
Mass Spectrometry
In the project we want to achieve real-time analysis. Samples have been previously collected on filters and our lab has done research that shows that the structure of the sample changes over time, showing they are not the most accurate representation of the original molecular structure. By introducing the sample into the machine directly, we hope to obtain more accurate analyses. We are also interesting in gain structural information. In order to understand how aerosols impact us, we have to identify the components of the structure. Lastly, we are interested in studying the different compounds in a complex mixture such as organic and inorganic compounds as well as radicals. In order to incorporate all these things, we used mass spectrometry.

5. How it Works Make Ions Ion Source Make Ions (LTP Probe) Mass Analyzer
(Ion Trap)
Manipulate Ions
Mass Spectrum
Mass Spectrometry is a method used to weigh gaseous compounds. First it makes ions using a ion source, manipulate ions using a mass analyzer, and detects ions using a detector. The detector then produces a Mass Spectrum. The Mass Spectrum shows the mass to charge ratios on the x-axis versus the relative intensity located on the y-axis. The unit of measurement for our mass is a Dalton which indicates mass on a molecular scale. For the purpose of this experiment our ion source is a LTP Probe and our Mass Analyzer is an Ion Trap.
Detector/
Computer
Relative Intensity
Detect Ions
Mass/Charge

6. Experimental Procedure+
To ion trap HV
3 L/min N2 I
Before we are able to ionize our sample, we must convert it to the aerosol phase. To do this we use a pyrolysis chamber. Pyrolysis is the decomposition of organic material at high temperatures without oxygen. After the aerosol is produced out the top, it is hit by the plasma from the Low-Temperature Plasma probe. The plasma ionizes the sources of the gas molecules creating gaseous ions that then enter the ion trap.
400 °C

7. Experimental Procedure
Mass Analyzer
3D Quadrupole Ion Trap
Compact
Sensitive
High product retention
As discussed before, our mass analyzer is an ion trap. In particular a three dimension quadrupole ion trap. The ion trap is ideal because it is compact meaning it doesn’t take up a lot of space, it is sensitive when detecting changes between the mass to charge ratios, and it maintains a lot of its products which is important for us.

8. Results- Cellulose Positive Ion Detection97
111
127
137
143
149
163
177
191
205
219
229
243
257
279
0.0
0.5
1.0
1.5
2.0
Intensity x 105
100
120
140
160
180
200
220
240
260
280
m/z
Over the past couple of months, I have been collecting data about cellulose and lignin. In this image, there is a mass spectrum taken on Cellulose. However, just this mass spectrum doesn’t tell us a lot.

9. Previously Identified Compounds in Cellulose
3,5-dihydroxy-2-methyl-4H-pyran-4-one
142 Da
5-hydroxymethyl-furfural
126 Da
Furfural
96 Da
Levoglucosenone
Lu, Q., Yang, X.-C., Dong, C.-Q., Zhang, Z.-F., Zhang, X.-M., Zhu, X.-F. Influence of pyrolysis temperature and time on the cellulose fast pyrolysis products: Analytical Py=GC/MS study. J Anal App Pyrol, 2011, 92,
Levoglucosan
162 Da
Evans, R. J., Milne, T. A. Molecular Characterization of the Pyrolysis Biomass. 1. Fundamentals. Energ Fuel, 1987, 1,
2-methyl-3-hydroxy-4-pyrone
Syringaldehyde
182 Da
4-ethylsringol
2,6-dimethoxyphenol
154 Da
My first step in learning more about the structure of the cellulose aerosol, I look at previously identified compounds in cellulose. However, I came across a problem. Several of them have the same mass, meaning they would ionize to same the mass to charge ratio. In order to differentiate them, we took our analysis to the next step.

10. Tandem Mass Spectrometry (MS/MS)
P+ gains energy
from collision
N and P+ collide
P1+
P3+
P2+
P4+
P+ dissociates into
fragment ions
We performed a process called Tandem Mass Spectrometry. First we isolate a particular ion. For this example it is lable as P+. The P+ collides with a neutral species label N. The collision gives the ion more energy which then causes it to break apart. By observing what the ion breaks into, we can learn more about the structure of the ion and differentiate it from other ions of similar masses.

11. MS/MS 155 Da 2,6-Dimethoxyphenol Standard Cellulose Aerosol Product95
123
140
155 2 4 6 8
Intensity x 105 80 90
100
110
120
130
150
m/z
2,6-Dimethoxyphenol Standard 81 83 95 99
109
111
123
127
137
140
155
0.00
0.25
0.50
0.75
1.00
1.25
Intensity x 104 80 90
100
110
120
130
150
m/z
Cellulose Aerosol Product
Here is example of what Tandem Mass Spectrometry looks like. For both we isolated the ion of mass 155 Da. We then performed the process and took a mass spectrum of the products. On this slide we compare the standard from the one I got from the cellulose aerosol. We see several of the same product ions. Although they don’t match perfectly, it is a possibility that the 2, 6 dimethoxyphenol standard is contained in cellulose but also another compound causing there to be more product ions in the cellulose aerosol.

12. MS/MS 127 Da 3-Hydroxy-2-Methyl-4-Pyrone Standard63 71
109
114
127
250
500
750
1000
1250
Intensity 60 70 80 90
100
110
120
m/z
3-Hydroxy-2-Methyl-4-Pyrone Standard 69 71 81 83 85 97 99
109
127
1000
2000
3000
Intensity 60 70 80 90
100
110
120
m/z
Cellulose Aerosol Product
However, not all of our standards are match. For example, the standard contains 114 which was not contained in our cellulose aerosol product. For that reason, it is very unlikely we have this compound in our aerosol. However, this is only one mass spectrum of many that doesn’t match a standard. A way to understand how all these compounds relate to each other is by creating a dissociation map.

13. Results- Cellulose Positive Ion Detection Dissociation Map
279
261
251
219
191
177
205
149
163
217
171
143
243
201
139
257
229
183
155
137
By creating a dissociation map, I can see that a lot of the compounds break down to the same product compound. We also see a few common losses of 18, 28, 42, 44, and 46.
Most Common Losses
-46 Da: C2H6O, CH2O2
-44 Da: C2H4O, CO2
-42 Da: C2H2O
-28 Da: CO, C2H4
-18 Da: H2O
127
111 93
109 97

14. Results- Cellulose Negative Ion Detection
113
127
141
157
171
185
205
227
241
255
269
277
283
297
309
325
500
1000
1500
2000
Intensity
100
125
150
175
200
225
250
275
300
m/z
To continue our research, I looked at another method for anaylsis. In addition to Positive Ion Detection that I showed before, I looked at Negative Ion Detection. The difference between the two ion detections is that with positive ion detection the functional group accepts a H+ ion giving it a positive charge while during in negative mode the functional group loses a H+ ion producing a negative charge. For example, in both spectrim we see In positive mode, the original compound was 126 and gained a H+ ion making the ion In negative more, the original compound was 128 and loss a H+ ion to become an ion of 127 mass.

15. MS/MS 161 Da Levoglucosan Standard Cellulose Aerosol Product Intensity71 73 85 89 97 99
101
113
125
129
143
161
500
1000
1500
2000
2500
Intensity 70 80 90
100
110
120
130
140
150
160
m/z
Levoglucosan Standard 71 73 85
101
113
129
143
161
500
1000
1500
2000
Intensity 70 80 90
100
110
120
130
140
150
160
m/z
Cellulose Aerosol Product
I completed the same comparison between the standards and cellulose and aerosol and see that some match with a few differences. 89 97 99
125

16. MS/MS 153 Da 2,6-Dimethoxyphenol Standard Cellulose Aerosol Product
125
138
151
153
0.0
0.5
1.0
1.5
2.0
Intensity x 104
120
130
135
140
145
150
155
m/z
2,6-Dimethoxyphenol Standard
125
135
153 10 20 30 40 50
Intensity
120
130
140
145
150
155
m/z
Cellulose Aerosol Product
Some match very well while others not so well.

17. Results- Cellulose Negative Ion Detection
277
289
297
283
219
233
261
269
255
241
227
229
217
205
183
I created a similar dissociation map and noticed the same common losses.
Most Common Losses
-46 Da: C2H6O, CH2O2
-44 Da: C2H4O, CO2
-42 Da: C2H2O
-28 Da: CO, C2H4
-18 Da: H2O
185
155
171
157
141
127
113

18. Results- Lignin Positive Ion Detection
112
124
141
149
154
167
182
196
210
219
233
247
257
271
279
287
305
321
2000
4000
6000
8000
Intensity
100
125
150
175
200
225
250
275
300
m/z
Right now in my research, I have began to study Lignin. I started looking at positive ion detection. In future studies, I hope to learn more about the molecular structure of the lignin aerosol.

19. Weird things +18, -28 (Lignin Positive Ion Detection)
-15 (Cellulose Negative Ion Detection) 83 97
111
121
129
139.
147
157
175 50
100
150
Intensity 80 90
110
120
130
140
160
170
m/z
Over the course of this project, I have noticed some things I have titled as weird things. First off in the top, we isolated 157 and fragmented it using tandem mass spectrometry. I saw a loss of ten which is very uncommon for having only carbon, hydrogen, and oxygen. So I expanded the mass spectrum, and I see a gain of 18. Meaning that 157 probably gained 18 and loss an overall loss of 28, one of the common losses I saw before. Another thing I noticed is at the bottom was a loss of 15. We isolated 187 and fragmented it using tandem mass spectrometry. WE see the common loss of 18 at 169 but also the a loss of 15 at This is uncommon in a ion trap due to slow heating. 75 87 97
111
125
141
143
159
169
187 10 20 30 40
Intensity 80
100
120
140
160
180
m/z
172

20. Summary Some peaks match those of standards
Some peaks do not match previously identified compounds
Weird things are occurring in MS/MS
Starting to understand how cellulose and lignin break down in order to identify compounds formed by pyrolysis
In summary, we have noticed that some peaks match those of standards while some don’t. We see a few weird things going. We are starting to understand how cellulose and lignin break apart in order to identify compounds formed by pyrolysis

21. What I’ve Learned How to use a mass spectrometer
How to analyze mass spectra
Some aspects of organic and analytical chemistry
It is not the end of the world if I break the instrument
Over the course of this project, I have learned how to use a mass spectrometer and how to analyze mass spectra. I also learned some aspects of organic and analytical chemistry. However, most importantly, I have learned that it is not the end of the world if I break the instrument. It can most of the time be fixed.

22. Plans for the future Take analytical and organic chemistry
Continue lab research in the Glish lab
My plans for the future are to take analytical and organic chemistry. I plan to also continue research in the Glish lab.

23. The Lab
In closing, I would like to show you a typical day for me. So on the left I have the monitor that I spend my mornings looking at. And on the right this is the complex wiring and machinery that I set up and work on. Voltages and everything.

24. Thanks and Acknowledgements
Sandra Spencer- Graduate Student Mentor
Gary Glish- Faculty Advisor
Other members of the Glish Lab
Brandon Santiago
Dr. Parikh
Dean Woodard
Monica Richards
Office for Undergraduate Research
I would like to thank my graduate student Sandra Spencer and faculty advisor Gary Glish for introducing me to such a new concept and making my summer enjoyable. I would also like to thank other member of the Glish Lab especially Brandon Santiago who could not make it today for your support and showing me around the ropes. I would like to thank Dr. Parikh, Dean Woodard, Monica Richards, and the Office of Undergraduate Research for this opportunity.

25. Questions?