LIBS uses a highly energetic laser pulse to induce breakdown of a sample's surface, atomizing and exciting it. The spectrometer then analyzes the light emitted from the laser-induced plasma. LIBS allows for rapid, multi-elemental analysis of solids, liquids, and gases with little to no sample preparation. It has applications in pharmaceutical analysis, environmental monitoring, metallurgy, and more. Recent developments have improved LIBS sensitivity and enabled techniques like depth profiling of multilayer samples.

1. LASER INDUCED BREAKDOWN
SPECTROSCOPY
B.PAVANI PADMA PRIYA
PHARMACEUTICAL ANALYSIS AND QUALITY
ASSURANCE
ROLL NO.-10VV1S2308
J.N.T.U COLLEGE OF ENGINEERING,VIZIANAGARAM.

2. contents
 Introduction
Principle
Instrumentation: Design
Operation
Advantages
Limitations
Applications
Recent scientific and technological
developments
Research articles
References

3. LASER-INDUCEDBREAKDOWN
SPECTROSCOPY (LIBS)
INTRODUCTION:
 Laser Ablation : Removing material from a sample surface by
irradiating it with a laser beam.
 After nearly 30 years of study, laser ablation has become the
basis of a new chemical analysis technology.
 Two approaches are: 1) LIBS,(part-per-million sensitivity)
2) LA-ICP-MS(parts-per-billion sensitivity).

4. Principle
LIBS: TYPE of AES which uses a highly energetic laser pulse as
the excitation source.
Laser is focused to form a plasma, which atomizes and excites
samples until it ionises and analysed by a spectrometer.
The obtained spectra consist of lines corresponding to the
elements evaporated from the sample surface.

5. INSTRUMENTATION: DESIGN
 LIBS system consists of :
 Laser :- Nd:YAG, and Eximer.
 Spectrometer :- either a monochromator / a polychromator
 Fiber optics
 Detector:- PMT / CCD(respectively to the spectrometer used)
attached to a spectrograph analyzes the collected plasma
light and this is coupled to a PC which can rapidly process
and interpret the acquired data.

7. INSTRUMENTATION: OPERATION
 Operate by focusing the laser onto a small area at the
surface of the specimen; generates a plasma plume with
temperatures in excess of 1,00,000 K.
•

8.  Based on physical composition, laser induced plasma can
be divided into three regions
 Region-I: (central or core region) the
temperature is maximum and species
are in ionised state.
 Region-II: (mid region) apart from ionised
species, both neutral and certain number
of molecular species are present.
 Region-III: (extended region) temperature
is comparatively lower and larger density
of molecular species present.

9.  As the plasma plume expands, constituent atoms in the ionized
gas become excited.
 Over just a few microseconds, the excited atoms began to relax,
resulting in characteristic spectral emissions by accompanying the
spectrometer and detector (delay generator) which accurately
gates the detector's response time.

10. ADVANTAGES
 Versatile sampling of solids, gases or liquids.
 Little or no sample preparation.
 Very small amounts of sample material.
 Analysis of extremely hard materials.
 Local analysis in micro regions offers a spatial resolving power.
 Possibility of simultaneous multi-elemental analysis.
 Potential for direct detection in aerosols.
 Simple and rapid analysis.

11. LIMITATIONS
 Increased cost and system complexity.
 Difficulty in obtaining suitable standards (semi-quantitative).
 Large interference effects ( in the case of LIBS in aerosols,
the potential interference of particle size).
 Detection limits are generally not as good as established
solution techniques.
 Poor precision.
 Possibility of ocular damage by the high-energy laser pulses.

12. APPLICATIONS
• LIBS at the Industries:
Pharmaceuticals**:-
-analysis of drug and lubricant in tablets
-analysis of saline solution
-drug mapping
-homogeneity of samples
Environment:-
-detection of contaminants
-industrial effluents

13. Metallurgy:- solid or molten alloys (Al, Cu, Zn, Mg, steel, Co, Ni,Cr)
- process fluids
- galvanized steel
- molten salts
- depth profiling
Other Organics:- paper
- polymer
- wood
Minerals:- detection of various elements (Au, Cu, Ni, Fe, C, Ca, Al,
Mg, Si,Ti) in ore and ore slurry.

14. RecentScientificand Technological
Developments
• Increase in sensitivity by 1 to 2 orders of magnitude using
double-pulse laser bursts or mixed-wavelength pulses.
• LIBS analysis of multilayer samples with high depth resolution
micro-mapping of heterogeneous samples.
• One-shot multielemental analysis using Échelle spectrograph
tunable laser.
• Hyphenated techniques with Raman and fluorescence
spectroscopy.
• Use of femtosecond laser for LIBS applications.

15. RESEARCH ARTICLES
 Quantitative analysis of gallstones using laser-induced breakdown
spectroscopy.
• VK Singh, V Singh, AK Rai, SN Thakur ;Applied Optics, Vol. 47, Issue 31,
pp. G38-G47 (2008), opticsinfobase.org.
 Identification and discrimination of Pseudomonas aeruginosa
bacteria grown in blood and bile by laser-induced breakdown
spectroscopy.
SJ Rehse, J Diedrich; Received 23 May 2007; Accepted 23 July 2007,Science
direct.com.
 Variational study of the constituents of cholesterol stones by laser-
induced breakdown spectroscopy.
VK Singh, V Rai - Lasers in Medical Science, 2009 – Springer.com.

16. CONCLUSION
 After nearly many years of study, LIBS has become the basis of
a new chemical analysis technology.
 Mars science laboratory mission are planning to take the LIBS
instrument to the mars in 2012.

17. REFERENCES
• www.appliedspectra.com/technology/LIBS.html
• www.springer.com
• www.ncbi.nlm.nih.gov
• www.appliedspectra.com
• www.rsc.org/publishing/journals
• www.oceanoptics.com/products/libs.asp
• en.wikipedia.org/wiki/Laserinducedbreakdownspectroscopy
• www.eproceedings.org
• www.photonics.cusat.edu/Research_Laser Induced
Plasma.html