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WHAT IS THE FTIR?
WHAT IS ITS PURPOSE?
WHY USE THIS
INSTRUMENT AS PER
OTHERS?
MORE INSIDE
INFORMATION ON FTIR
INTRODUCTION
WHAT IS FTIR?
FOURIER TRANSFORM INFRARED
SPECTROSCOPY
MEASURES INFRA RED RADIATION BETWEEN
THE RANGE 450cm-1 TO 4000cm-1 or (2,500 nm to
22,000 nm)
PURPOSES?
H O W AT T E N UAT E D T O TA L R E F L E C TA N C E I R W O R K S
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
REASON FOR USING THIS INSTRUMENT
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
1.6 1.8 2 2.2 2.4 2.6 2.8 3
-22800
-22600
-22400
-22200
-22000
Plot of peak area 2600cm-1 to
4000cm-1 versus log of time
Log of Time
Peak A
rea
1.6 1.8 2 2.2 2.4 2.6 2.8 3
-4000
-3500
-3000
-2500
-2000
-1500
-1000
-500
0
Plot of peak area 1200cm-1 to 1900cm-1
versus log of time
Log of Time
Peak A
rea
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
diluted blood (0.1ml)
diluted blood (0.01ml)
diluted blood (0.001ml)
diluted blood (0.0001ml)
Name
Date Thursday, March 20 2014
Sample 054 By Administrator Date Thursday, March 20 2014
Date Thursday, March 20 2014
Date Thursday, March 20 2014
Description
4000 4503500 3000 2500 2000 1500 1000
104
31
35
40
45
50
55
60
65
70
75
80
85
90
95
100
cm-1
%T
RESULTS OF SERIAL DILUTION
0.5 1 1.5 2 2.5 3 3.5 4 4.549
49.2
49.4
49.6
49.8
50
50.2
50.4
f(x) = − 0.287 x + 50.575R² = 0.977151669731302
Plot of peak area ~3307cm-1 versus log of dilution factor
LOG OF DILUTION
% T
RA
NSM
ITT
AN
CE
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
burned blood drop
Name
Sample 062 By Administrator Date Thursday, March 27 2014
Description
4000 4503500 3000 2500 2000 1500 1000
101
31
35
40
45
50
55
60
65
70
75
80
85
90
95
cm-1
%T
3325.10cm-1, 51.19%T
1638.23cm-1, 72.02%T
4000.00cm-1, 99.36%T 2595.67cm-1, 98.83%T 1940.96cm-1, 98.23%T
1324.96cm-1, 91.18%T
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
blood with bleach 1
Name
Sample 068 By Administrator Date Tuesday, April 01 2014
Description
4000 4503500 3000 2500 2000 1500 1000
102
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
cm-1
%T
3350.93cm-1, 50.49%T
1635.46cm-1, 70.43%T
3999.00cm-1, 100.02%T 2610.68cm-1, 99.12%T 2012.67cm-1, 97.85%T
1166.82cm-1, 91.25%T
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-of-Near-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
