Blood Analysis using ftir spectroscopy

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FOR INVESTIGATIVE PURPOSES
INTRODUCTION
 WHAT IS THE FTIR?
 WHAT IS ITS PURPOSE?
 WHY USE THIS
INSTRUMENT AS PER
OTHERS?
 MORE INSIDE
INFORMATION ON FTIR
WHAT IS FTIR?
PURPOSES?
 FOURIER TRANSFORM INFRARED SPECTROSCOPY
 MEASURES INFRA RED RADIATION BETWEEN THE
RANGE 450cm-1 TO 4000cm-1 or (2,500 nm to 22,000 nm)
H O W A T T E N UA T E D T O T A L R E F L E C T A N C E I R
WORKS
REASON FOR USING THIS
INSTRUMENT
 Other techniques that were
used in the past gave false
negative and false positive results
for the presence of blood
 This instrument is easier to
use as per the salt plate FTIR
OBJECTIVES
 Test for the presence of blood under certain conditions
•
•
•
•
Burning blood
Serial dilution of blood
Denaturing by using bleach
Aging over a period of time
THE SPECTRA OF BLOOD
-COOH
-NH-C-H Stretch
METHODS
 Aging Blood
•
•
•
•
•
•
Prepare slides with blood drop
on each.
Date them
Place a drop by itself on the
spectrometer to analyze spectra
on the first day
Leave the other slides to dry
When retesting it, wet a swab
with distilled water and swab as
much blood onto the swab
Dab it onto the spectrometer
and run the spectra
RESULTS OF AGED BLOOD
Plot of peak area 2600cm1 to 4000cm-1 versus log
of time
Plot of peak area 1200cm-1 to
1900cm-1 versus log of time
0
0
-22200
0
1
2
-22400
-22500
-22600
1
1.5
2
4
-1000
-1500
-2000
-2500
-3000
-22700
-22800
3
Peak Area
Peak Area
-22300
0.5
-500
-3500
Log of Time
-4000
Log of Time
2.5
3
3.5
METHODS
 Serial Dilution
•
•
•
•
•
Obtain 10ml of blood
Pipette 9ml from the 10ml and
then add 1ml water
After this dilution obtain
another 9ml of the previous
sample and add another 1ml of
water
Shake well after adding water to
each sample
Repeat process 4 times
RESULTS OF SERIAL
DILUTION
104
100
95
90
85
80
75
%T
70
65
60
55
50
45
40
35
31
4000
3500
3000
2500
2000
1500
cm-1
diluted
diluted
diluted
diluted
Name
blood (0.1ml)
blood (0.01ml)
blood (0.001ml)
blood (0.0001ml)
Description
Date Thursday, March 20 2014
Sample 054 By Administrator Date Thursday, March 20 2014
Date Thursday, March 20 2014
Date Thursday, March 20 2014
1000
450
RESULTS OF SERIAL
DILUTION
Plot of peak area ~3307cm-1 versus log of dilution
factor
50.4
50.3
% TRANSMITTANCE
50.2
50.1
50
49.9
49.8
49.7
49.6
y = -0.287x + 50.575
R² = 0.9772
49.5
49.4
49.3
0
0.5
1
1.5
2
2.5
LOG OF DILUTION
3
3.5
4
4.5
METHODS
 Burning Blood
•
•
•
•
•
Get a watch glass and place a
drop of blood on top
Get a ring stand with clamp
and set it up with the watch
glass on top of the clamp
Light a Bunsen burner and
burn the sample until it turns
completely black and
unnoticeable as blood
Wet a swab with water then
swab the sample
Use FTIR to test the sample
RESULTS OF BURNING
BLOOD
4000.00cm-1,
101 99.36%T
2595.67cm-1, 98.83%T
1940.96cm-1, 98.23%T
95
1324.96cm-1, 91.18%T
90
85
80
75
%T
70
1638.23cm-1, 72.02%T
65
60
55
50
3325.10cm-1, 51.19%T
45
40
35
31
4000
3500
3000
2500
2000
cm-1
Name
burned blood drop
Description
Sample 062 By Administrator Date Thursday, March 27 2014
1500
1000
450
METHODS
 Bleaching Blood
•
•
•
•
•
Obtain a test tube and a bottle
of bleach
Place 0.5ml of blood into the
test tube using a Pipette
Fill the test tube half way with
bleach
Stir the solution in the test tube
Pipette some of the sample
from the tube and test it on the
FTIR spectrometer
RESULTS FOR BLEACHED
BLOOD
CONCLUSION
 The instrument is reliable in detecting the presence of blood under
all four conditions, however it does not detect a simultaneous trend
with aged blood
 Easier to move around
REFERENCES

Charlotte-Maria Orphanou BSc (Hons), D. H. (n.d.). A Preliminary Investigation into the use of FTIR
Spectroscopy . Retrieved from Staffordshire University:
http://www.staffs.ac.uk/assets/FSSocPoster_tcm44-55830.pdf

Edita Botonjic-Sehic, C. W. (2009, February 1). Forensic Application of Near-Infrared Spectroscopy:
Aging of Bloodstains. Retrieved from Advanstar:
http://www.spectroscopyonline.com/spectroscopy/Near-IR+Spectroscopy/Forensic-Application-ofNear-Infrared-Spectroscopy/ArticleStandard/Article/detail/583780?contextCategoryId=36822

Sciences, P. L. (n.d.). FT-IR Spectroscopy: Attenuated Total Reflectance (ATR). Retrieved from Perkin
Elmer : http://www.utsc.utoronto.ca/~traceslab/ATR_FTIR.pdf

Serology: Blood and Other Bodily Fluids. (2013). Retrieved from Indigent Defense Services:
http://www.ncids.com/forensic/serology/serology.shtml

Stephen L. Morgan, P. M. (2011, July). Rapid Visualization of Biological Fluids at Crime. Retrieved
from NCJRS: https://www.ncjrs.gov/pdffiles1/nij/grants/235286.pdf
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