1. Role of Raman Spectroscopy in Bio & Agriculture
Mushtaq Ahmed
National Institute of Lasers and Optronics (NILOP)

2. Outline Introduction Applications
Food
Geology
Gemology
Material
Medical
Raman Spectroscopic activities at NILOP

3. History 1923 – Inelastic light scattering predicted by A. Smekel
1928 – Landsberg and Mandelstam see unexpected
frequency shifts in scattering from quartz
1928 – C.V. Raman and K.S. Krishnan see “feeble
fluorescence” from neat solvents
1930 – C.V. Raman wins Nobel Prize in Physics
1961 – Invention of laser makes Raman experiments
reasonable
1977 – Surface-enhanced Raman scattering (SERS) is
discovered
1997 – Single molecule SERS is possible
Filtered Hg arc
lamp spectrum
C6H6
Scattering
First Raman Spectra

4. Layout of Original Raman Experiment
Presently used dispersive Raman system lay out
Precise measurements were made with this quartz spectrograph and first made public by Raman in a lecture in Bangalore on March 16, 1928.

5. Raman Scattering Selection rule: Dv = ±1 Overtones: Dv = ±2, ±3, …
Incident
Light
Scattered Light
Must also have a change in polarizability
Classical Description does not suggest any difference
between Stokes and Anti-Stokes intensities

6. When light interacts with a vibrating diatomic molecule, the induced
dipole moment has 3 components:
Rayleigh scatter
Anti-Stokes Raman scatter
Stokes Raman scatter

7. Raman Intensities Radiant power of Raman scattering:
s(nex) – Raman scattering cross-section (cm2)
nex – excitation frequency
E0 – incident beam irradiance
ni – number density in state i
exponential – Boltzmann factor for state i
s(nex) - target area presented by a molecule for scattering

8. 1 in 107 photons is scattered in elastically
Infrared
(absorption)
Raman
(scattering)
v” = 0
v” = 1
virtual
state
Excitation
Scattered
Rotational Raman
Vibrational Raman
Electronic Raman

9. Raman scattering Cross-Sections
Process
Cross-Section of
s (cm2)
absorption UV
10-18 IR
10-21
emission
Fluorescence
10-19
scattering
Rayleigh
10-26
Raman
10-29 RR
10-24
SERRS
10-15
SERS
10-16
s(nex) - target area presented by a molecule for scattering
Table adapted from Aroca, Surface Enhanced Vibrational Spectroscopy, 2006

10. Raman scattering Cross-Sections
lex (nm)
s ( x cm2)
532.0
0.66
435.7
1.66
368.9
3.76
355.0
4.36
319.9
7.56
282.4
13.06
CHCl3:
C-Cl stretch at 666 cm-1
Table adapted from Aroca, Surface Enhanced Vibrational Spectroscopy, 2006

11. Raman Strength & Limitations
Easily identify chemical structure – (Figure print technique)
Widely applicable for various materials.
Samples can be solid or aqueous (water is a weak Raman scattered)
Little or no simple preparation required
Non-invasive, non-destructive method.
Remote control with the fiber optics
Fluorescence especially when the incident light goes to blue
Technique and cost or laser sources
Low excitation probability : 1per 107 or 108
Specially refrained by optical limit
Distanced Raman

12. Raman Spectroscopic Applications

13. Applications in Daily Life
Fingerprinting the universe
Advantages:
Fingerprint spectra (molecular signature)
Structural orientation/conformation
Intermolecular interactions
Laser-based spectroscopy
Small sample size (0.5 – 1.0L) – Clinical use
Test low concentration samples (single molecule sensitivity)
Used in detecting explosives, nuclear waste, water pollution, etc. Useful for police officers, medical staff, forensic scientists

14. Raman Applications Moving from Discovery to Practice
Pharmaceutical/Biomedical
Material Science/Nanotechnology
Forensic/anti-crime/anti-terrorism
Gemmology/geology/mineralogy
Archaeology/art/heritage
……….
Anywhere need identifications with close proximity between inspecting tools (including fiver laser source and examples.
Easily identify chemical structure-finger print technique
Widely applicable for various materials
Simples can be solid or aqueous (water is a weak Raman scattered)
Little or no simple preparation required.
Non-invasive, non-destructive method.
Remote control with fiber optics

15. Raman Morphological Model Basis Spectra

16. Raman spectroscopy of Breast Normal & Cancerous Tissue

17. Raman Spectroscopy in Food Sciences

18. Material Science

19. X-Rays Analysis & Raman Spectroscopy

20. Raman Spectroscopic Activities at NILOP

21. Raman spectrometer with microscope

22. Raman Spectra of Leaf Normal & Rusted
Raman signal intensity
Raman shift (cm-1)

23. Raman spectra of male and female feather

24. Raman Spectra – Edible oils, spreads and ghee
Desi ghee (home made), Desi ghee (market), Banaspati ghee (I, II, III)
Cooking oil, Sunflower oil, Canola oil, Canolive oil, Olive oil
Raman intensity (a. u.)
Margarine, sunflower spread, Rapeseed spread, Lurpak spread, Extra virgin olive oil spread
Raman shift (cm-1)

25. Raman Spectra – Edible oils, Spreads and Ghee
Rapeseed spread
Extra virgin olive oil spread
Cooking oil (blend of can, soy, sun)
Sunflower oil
Canola oil
Canolive oil (blend of olive, canola, sun)
Olive oil
Second principal component (20.2) %
Desi ghee (home made)
Desi ghee (market)
Banaspati ghee (I)
Banaspati ghee (II)
Banaspati ghee (III)
Mmargarine
Sunflower spread
Canola and sunflower spread
First principal component (45.3) %

26. Diagnosis of Hepatitis C blood Serum (body fluids)

27. Diagnosis of Hepatitis C Principal Component Analysis
Normal blood sera samples
HCV infected blood sera samples
First principal component (68.1 %)

28. Diagnosis of Dengue Virus Infection & Malaria in blood serum (body fluids)
Journal of Biomedical Optics 20(1), (January 2015)

30. Raman Spectra of normal Sera (green) and Pure Lactate (Red)

31. Raman Spectra of normal Blood Sera with addition of Lactate

32. Non-invasive Diagnosis of Malaria Using Laser
Transdermal Detection

33. Non-invasive Diagnosis of Malaria Using Laser Transdermal Detection
Laser Parameters:
Wavelength: 532 nm
Pulse: ps
Fluence: 36 mJ/cm2
Acoustic traces obtained in vitro in response to a single laser pulse exposure

34. Collaboration NORI Hospital Islamabad PAEC General Hospital Islamabad
IRNOM Hospital Peshawar
Mayo Hospital Lahore
Institute of Public Health Lahore
Holy Family Hospital
Department Biotechnology QAU Islamabad
National Institute of Physics (Nano-medicine)
NARC (National Agricultural Research Council)
NIA (Nuclear Institute of Agriculture)
NIFA (National Institute of Food and Agriculture)
NIBGE (National Institute for Biotechnology and Genetic Engineering)
NIAB (Nuclear Institute of Agriculture and Biology)
Institute of Photonics Technology GENA Germany
Biophotonics Group, Lund University Seweden

35. International research collaborators
Prof. Dr. Stefan Andersson-Engels
Biophotonics Group,
Atomic Physics Division,
Lund University,
Sweden.
Prof. Dr. Jürgen Popp
Institute of Photonic Technology (IPHT),
Institute of Physical Chemistry and Abbe
Center of Photonics,
Jena University, Germany.
Prof. Vanderlei Salvador Bagnato
Universidade de São Paulo - Instituto de Física de São Carlos

36. Research collaboration
Thanks for listening
Welcome for
Research collaboration
Light for Health