Raman imaging -Anjali Devi J S
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Raman imaging is application of Raman sprectroscopy for medical diagnostics and bioimaging. It emerges as a promising noninvasive imaging technique in biomedical research.
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Raman imaging -Anjali Devi J S
- 1. Raman ImagingRaman Imaging Anjali Devi J S Research Scholar University of Kerala | Department of Chemistry
- 2. 1921 Story... Ref: Nature, 1921,108,367; Nature, 1921,108, 402-403. C. V. Raman's experiments on the colour of sea-due to molecular scattering 1871 Rayleigh scattering-colour of sea is the just reflection of sky Lord Rayleigh Sir C.V. Raman in the sculpture park of Nehru Science Centre, Mumbai, India
- 3. Ref: Nature, 1922,109,444-445; Nature, 1928,121,501-502 Raman's monograph -molecular scattering and quantum structure of light-get published. 1922 Story Continues... 1928 C. V. Raman and K. S. Krishnan: discovery of Raman effect experiments on 28 Feb 1930 Sir Chandrasekhara Venkata Raman awarded Nobel Prize in Physics K. S. Krishnan C. V. Raman
- 4. Raman Scattering Vs Rayleigh scattering Raman Effect Rayleigh scattering Elastic scattering of photon Inelastic scattering of photon Scattered at lower frequency (Stokes Raman scattering) Scattered at higher Frequency (Anti Stokes Raman scattering) Scattered at same frequency(Rayleigh scattering) Intensity decreases Ref: Atkin's Physical Chemistry, 9th edn. Oxford University Press.
- 5. Raman Scattering Vs Rayleigh scattering Ref: Chem. Soc. Rev., 2012, 41, 7085–7107
- 6. 1974 Ref: Chem. Phys. Lett., 1974, 26, 163-166. Surface Enhanced Raman Scattering(SERS) Fleischmann et al. observed an unexpected large Raman scattering from pyridine adsorbed on electrochemically roughened silver Martin Fleischmann (29 March 1927 – 3 August 2012)
- 7. Raman Scattering Vs SERS Ref: Chem. Soc. Rev., 2012, 41, 7085–7107
- 8. How SERS...? electromagnetic enhancement (EM) chemical enhancement (CE) Mechanism Theoretical electric field profile at λ =535 nm for the gold nanoparticle Ref: Chem. Soc. Rev., 2012, 41, 2740–2779; Chem. Rev. 2011, 111, 3888–3912
- 9. Ref: Chem. Soc. Rev., 2012, 41, 7085– How SERS...?
- 10. Bibliometric Analysis of the Publications & Citations Per Year number of citations in Raman endoscopy number of citations inRaman imaging AND disease Ref: Analyst,2013, 138, 3871–3884. Courtesy:ISI Thomson Web of Science (http://wos.mimas.ac.uk/) for the period 1992–2012 number of citations in spatially offset Raman AND disease number of publications in Raman AND disease number of citations in SERS AND disease
- 11. Ref: Chem. Rev. 2013, 113,1391-1428; Chem. Soc. Rev., 2012, 41, 7085–7107 Design SERS substrate (Au or Ag NP) Adsorption of Raman reporter Protective surface coating (PEG or silica) Design targetting ligand (antibody/ DNA/organic molecules) How Raman Imaging? -Design of SERS Tags 1 2 3 4
- 12. Design of SERS Tags Courtesy: http://images.iop.org/objects/ntw/journal/11/3/16/image1.jpg
- 13. Theoretical calculations of the local electromagnetic near field enhancement at the laser excitation wavelength of 632.8 nm : (a) an isolated Au nanosphere of 30 nm radius (using Mie scattering theory) ; adjacent nanosphere dimer (interparticle distance 3 nm) with (b) interparticle axis perpendicular and (c) parallel to the incident polarization.((b) and (c) using the FDTD method) (d) TEM image of a Au trimer cluster encapsulated in a silica shell and (e) the corresponding image of the calculated electromagnetic enhancement intensity profile at 632.8 nm. Theoretical Profile(photographs) of Electromagnetic field...... Ref: Nano Lett., 2005, 5, 1569–1574; J. Am. Chem. Soc., 2010, 132, 10903–10910
- 14. Raman Reporters for SERS Tags??? Nitrogen containing dye Sulfur containing dye Crystal violet Malachite green isothiocyanate(MGITC) Thio small molecules benzenethiol4-aminothiophenol Rhodamine B isothiocyanate(RBITC)
- 15. Typical Raman Reporters for SERS Tags Ref: Chem. Rev. 2013, 113,1391-1428 Type Example Linking mode Advantage Disadvantage Nitrogen containing dye Crystal violet N- Au (Ag) interaction Cheap Large Raman cross section Weak affinity to metal Weak signal stability Difficult surface coating Sulfur containing dye Malachite green isothiocyanate Rhodamine -6 -isothiocyanate S- Au (Ag) interaction Strong binding affinity Strong binding affinitySuitable for surface coating Limited type Hard to form Self assembled monolayer Thio small molecules 4- aminothiophenol benzenethiol S- Au (Ag) interaction Cheap Strong binding affinity Appropriate for Multiplexing Small Raman cross section
- 16. Surface Coating... Denatured Serum Albumin Thiolated Poly ethylene glycol Amphiphilic diblock copolymer Silica shellLiposomes Ref: Chem. Rev. 2013, 113,1391-
- 17. Strategies of Bioanalysis by SERS tags (a)Analyte induced SERS tag aggregation (b)Analyte changing Raman signature of the reporter (c)Fabrication of gold nanoarticle gold nanorod junction for protien detection Thrombin Thrombin Binding Aptamer
- 18. Analysis by SERS Tags.... Raman reporter dye Dye labelled Gold nanoparticle Dye labelled Gold nanoparticle Gold nanoparticle Ref:Small, 2012, 8, 707–714. Aggregation of the nanoparticles is caused by formation of the octahedral complex when Ni(II) is coordinated between NTA and histidine moieties present at the particle surface
- 19. dipicolinic acid (biomarker for anthrax) glutaric acid- Internal standard Ref: Anal. Chem., 2013, 85, 3297–3302. Raman Imaging- an example pyridine ring breathing vibration (of dipicolinate) at 1006 cm-1 the C–H stretching vibration (of glutaric acid) at 2934 cm-1 Detection limit-5 ppb (30 nM) SERS spectra of dipicolinic acid, a biomarker for Bacillus anthracis(pathogen for anthrax) spores, measured using citrate- reduced silver colloid and a portable 633 nm Raman spectrometer
- 20. Multiplexed Raman imaging Ref: Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 13511. (a) Raman map of 10 different SERS particles injected subcutaneously in a nude mouse. Panels below depict separate channels associated with each of th einjected SERS NPs. Grayscale bar to the right depicts the Raman intensity.(b) Graph depicting five unique Raman spectra, each associated with its own SERS batch. (c) Raman image of liver overlaid on digital photo of mouse, showing accumulation of all five SERS batches accumulating in the liver after 24 h post i.v injection. Panels below depict separate channels associated with each of the injected SERS NP batches.
- 21. Raman x−y maps of a G. lamblia cyst and a C. parvum oocyst Ref: J. Environ. Sci. Technol. 2009, 43, 1147. Optical image Raman map of the 1647 cm−1 RBITC peak Raman map of the 1360 cm−1 RBITC peak Raman intensity key Raman map of the 1618 cm−1 MGITC Raman map of the 1175 cm−1 MGITC
- 22. Techniques of Raman Imaging..... Surface enhanced Raman spectroscopy(SERS) Coherent anti-Stokes Raman spectroscopy (CARS) Stimulated Raman Scattering(SRS) Spatially offset Raman spectroscopy Ref: Analyst,2013, 138, 3871– R- Raman light L- Laser light
Hinweis der Redaktion
- The nature and natural phenomenon ia always a centre of mystery to man. Especially the colour of sea.. Rayleigh described rayleigh scatteringin 1871 and he proposed that the colour of sea is just the reflection of sky.It was during a sea voyage from India to England in 1921 that the brilliant Indian physicist C.V. Raman, another renowned experimentalist, conducted some on-board experiments which were later submitted to Nature in a letter called the ‘The Colour of the Sea’.Unable to accept Lord Rayleigh's explanation that the colour of the sea was just a refection of the colour of the sky, Raman's experiments showed that the colour of the seawas in fact a direct result of the molecular scattering of light and independent of absorption or the reflection of light from the sky.This was very closely followed by another letter to Natureconcerning the molecular scattering of light in liquids and solids
- These experiments opened up a deep interest in C.V. Raman and a new field of research on his return to Kolkata on the scattering of light as well as the publication of another article on the molecular diffraction and quantum structure of light in 1922. Raman and collaborators such as K.S. Krishnan began a of seminal experiments concerning the scattering of light in a large number of liquids, as well as theories about the potential applications of their experiments, which culminatedin their discovery of the inelastic scattering effect named after Raman in 1928 on 28 February,and his award of the Nobel Prize for Physics in 1930series
- A SERS tag is created by attaching intrinsically strong Raman scattering molecules (called Raman reporters) to the surface of plasmon-resonant Ag or Au NPs, thereby creating a known SERS spectrum of the Raman reporter. Then a biorecognition element such as an antibody may be added to render the tags with biostability, biocompatibility, and a specific binding feature.
- Several strategies including analyte-induced SERS tag aggregation, analytes induced alteration of the reporter’s Raman signature and SERS-tag based immunoassays, and have been developed to detect ions and biomolecules