1. Prescription for CrimeTM Drug Testing Lab 2 solutions

2. Known GC-MS data sheets
Oxycodone
Amphetamine
Methamphetamine
Cocaine
Ketamine

3. This graph is the GC plot for oxycodone

4. This graph is the GC plot for oxycodone
X-axis: time the material is on the column in minutes

5. Y-axis: peak height in mcounts
This graph is the GC plot for oxycodone
X-axis: time the material is on the column in minutes

6. may be a single component, but more testing is required to make sure this isn’t a cluster of components that haven’t separated

7. This graph is the MS plot

8. This graph is the MS plot
X-axis: mass to charge ratio of the sample
LOW mass
HIGH charge
HIGH mass
LOW charge

9. Y-axis: percent absorbance of the sample
This graph is the MS plot
X-axis: mass to charge ratio of the sample
LOW mass
HIGH charge
HIGH mass
LOW charge

10. multiple components, the “fingerprint” for this sample
LOW mass
HIGH charge
HIGH mass
LOW charge

11. What is our unknown sample?
Possibilities:
Oxycodone
Amphetamine
Methamphetamine
Cocaine
Ketamine

12. What is our unknown sample?
Oxycodone
Peaks at: 8 and 9 min
Peaks at: 23 min
The real unknown was too confusing, so I removed it and had you use the concentrations of the unknown.
43, 56, 58, 91, 150
70, 230, 315, 316, 317

13. What is our unknown sample?
Oxycodone

14. What is our unknown sample?
Amphetamine
Peaks at: 8 and 9 min
Peaks at: 7 min
43, 56, 58, 91, 150
42, 44, 91,136

15. What is our unknown sample?
Amphetamine

16. What is our unknown sample?
Ketamine
Peaks at: 8 and 9 min
Peaks at: 16.7 min
43, 56, 58, 91, 150
180, 182, 238, 240, 239

17. What is our unknown sample?
Ketamine

18. What is our unknown sample?
Cocaine
Peaks at: 8 and 9 min
Peaks at: 6.7, 11 min
43, 56, 58, 91, 150
42, 82, 122, 150, 152, 156, 181

19. What is our unknown sample?
Cocaine

20. What is our unknown sample?
Methamphetamine
Peaks at: 8 and 9 min
Peaks at: 8 min
43, 56, 58, 91, 150
56, 58, 91, 150

21. What is our unknown sample?
MATCH!
Unknown
Methamphetamine
Peaks at: 8 and 9 min
Peaks at: 8 min
43, 56, 58, 91, 150
56, 58, 91, 150

22. What is our unknown sample?
Methamphetamine
No 9 min peak
No 43 peak
Maybe the sample was cut or we are seeing additional byproducts of the manufacturing process?

23. 0.25 milligrams of meth per milliliter of solvent in the sample
Lab 2, part B
Four concentrations of meth in this analysis:
0.25 mg/ml
0.50 mg/ml
0.75 mg/ml
1.00 mg/ml
0.25 milligrams of meth per milliliter of solvent in the sample

24. Measure the peaks of four concentrations with a ruler (mm)
0.25 mg/ml of meth
GC peak at 8 min
Baseline to peak measurement: mm

25. Measure the peaks of four concentrations with a ruler (mm)
0.50 mg/ml of meth
GC peak at 8 min
Baseline to peak measurement: 47 mm

26. Measure the peaks of four concentrations with a ruler (mm)
0.75 mg/ml of meth
GC peak at 8 min
Baseline to peak measurement: mm

27. Measure the peaks of four concentrations with a ruler (mm)
1.00 mg/ml of meth
GC peak at 8 min
Baseline to peak measurement: 89 mm

28. Make a scatter plot of the peaks in Excel

29. Make a scatter plot of the peaks in Excel
Input your measurements from the provided GC chart peaks

30. Make a scatter plot of the peaks in Excel
Insert tab, scatter chart button, scatter with only markers button

31. Make a scatter plot of the peaks in Excel
Select the chart, design tab, select data button

32. Make a scatter plot of the peaks in Excel
Add a legend entry (series)

33. Make a scatter plot of the peaks in Excel
Choose the series name (cell A1)

34. Make a scatter plot of the peaks in Excel
Choose the series name (cell A1)

35. Make a scatter plot of the peaks in Excel
Choose the series x values (cells A3:A6)

36. Make a scatter plot of the peaks in Excel
Choose the series y values (cells B3:B6)

37. Make a scatter plot of the peaks in Excel
Click OK

38. Make a scatter plot of the peaks in Excel
Right click one of the data points and select “add trendline”

39. Make a scatter plot of the peaks in Excel
Choose Linear, check display equation and r-squared value on chart

40. Make a scatter plot of the peaks in Excel
Delete the legend

41. Make a scatter plot of the peaks in Excel
Move the equation so you can read it easier

42. Make a scatter plot of the peaks in Excel
Layout tab, axis titles button, primary horizontal axis title, title below axis

43. Make a scatter plot of the peaks in Excel
Double click the axis title and re-name it “concentration of known solution (mg/ml)”

44. Make a scatter plot of the peaks in Excel
Layout tab, axis titles, primary vertical axis title, rotated title

45. Make a scatter plot of the peaks in Excel
Double click the axis title and re-name it “peak height (mm)”

46. Calculate the concentration of the unknown solution (meth)
Our equation from the trendline: y = 88.8x – 0.5
peak height = 88.8 * concentration – 0.5

47. Calculate the concentration of the unknown solution (meth)
Solve for x (concentration):
y = 88.8x – 0.5
y – 0.5 = 88.8 x
(y – 0.5) / 88.8 = x
concentration = (peak height – 0.5) / 88.8

48. Calculate the concentration of the unknown solution (meth)
The peak height for the unknown solution was 75.5 mm. Plugging this number into the concentration formula from the trendline, we get:
concentration = (peak height – 0.5) / 88.8
concentration = (75.5 – 0.5) / 88.8
concentration = mg/ml

49. Calculate the concentration of the unknown solution (meth)
To get a sense of what is happening, we plot this data point [0.844 mg/ml, 75.5mm] on top of the concentration graph
75.5
0.844

50. Calculate the percentage of the drug (meth)
Sample concentration: mg/ml
Original concentration: 2 mg/ml
0.844 mg/ml / 2 mg/ml = = 42.2%

51. Calculate the quantity of the drug (meth)
Drug concentration: 42.2%
Mass of powder collected by police: 13g
Drug quantity present:
0.422 * 13g = 5.48g