Mass spectrometry is an analytical tool useful for measuring the mass-to-charge ratio (m/z) of one or more molecules present in a sample. These measurements can often be used to calculate the exact molecular weight of the sample components as well. The principle is to ionize a sample, separate the resulting ions based on their m/z, and then detect and record the abundance of each ion. This information is then used to identify and quantify the components of the sample.

1. Mass
spectroscopy

2. INTRODUCTION :
• Mass spectrometry (MS) is an analytical technique that measures
the mass-to-charge ratio (m/z) of ions."
• "It provides information about the composition and structure of
molecules."
• This technique basically studies the effect of ionizing energy on
molecules.
• Now a day's mass spectrometry is used in many areas
including pharmaceutical, clinical, geological, biotechnology
and environmental.

4. PRINCIPLE
:• In this technique, molecules are bombarded with a beam
of energetic electrons.
• The molecules are ionized and broken up into many fragments,
some of which are positive ions. Each kind of ion has a
particular ratio of mass to charge, i.e. m/e ratio (value).
• For most ions, the charge is one and thus, m/e ratio is
simply the molecular mass of the ion.
• The ions pass through magnetic and electric fields to reach
detector where they are detected and signals are recorded to
give a mass spectra.

6. INSTRUMENTATION :
• A. Sample Inlet
• Sample stored in large reservoir from which molecules reaches
ionization chamber at low pressure in steady stream by a pinhole called
"Molecular leak".
• B. Ionization
• Atoms are ionized by knocking one or more electrons off to give positive
ions by bombardment with a stream of electrons. Most of the positive
ions formed will carry charge of +1.
• lonization can be achieved by:
• Electron ionization (EI-MS)
• Chemical ionization (CI-MS)
• Desorption Technique (FAB)

7. • C. Acceleration
• ions are accelerated so that they all have same kinetic energy.
• Positive ions pass through 3 slits with voltage in decreasing
order.
• Middle slit carries intermediate and finals at zero volts.
• D. Deflection
• ions are deflected by a magnetic field due to difference in their
masses.
• The lighter the mass, more they are deflected.
• It also depends upon the no. of +ve charge an ion is carrying;
the more +ve charge, more it will be deflected.

8. • E. Detection
• The beam of ions passing through the mass analyzer is
detected by detector on the basis of m/e ratio.
• When an ion hit the metal box, charge is neutralized by an
electron jumping from metal on to the ion.

9. • APPLICATION :
• Environmental monitoring and analysis (soil, water and air
pollutants, water quality, etc.).
• Chemical and Petrochemical industry - Quality control.
• Identify structures of biomolecules, such as carbohydrates,
nucleic acids
• Sequence biopolymers such as proteins and
oligosaccharides
• Determination of molecular mass of peptides, proteins, and
oligonucleotides.
• Monitoring gases in patients breath during surgery.
• Identification of drugs abuse and metabolites of drugs of
abuse in blood, urine, and saliva.

10. • Advantages:
• High Sensitivity:
• Mass spectrometry can detect and quantify even trace amounts of substances, making it ideal for analyzing samples with very
low concentrations.
• High Specificity:
• The mass-to-charge ratio (m/z) provides a unique fingerprint for each molecule, allowing for accurate identification and
differentiation of compounds.
• Versatility:
• Mass spectrometry can be used to analyze a wide range of substances, including small molecules, proteins, polymers, and even
complex mixtures.
• Structural Information:
• Fragmentation patterns in mass spectra can provide valuable information about the structure and chemical properties of
molecules.
• Isotopic Information:
• Mass spectrometry can determine the isotopic composition of a sample, which is useful in various applications, such as carbon
dating and tracing metabolic pathways.
• Coupling with other Techniques:
• Mass spectrometry is often coupled with separation techniques like Gas chromatography (GC-MS) and Liquid chromatography
(LC-MS) greatly enhancing the ability to analyze complex mixtures.
• Disadvantages:
• Cost:
• Sample Preparation:
• Some samples require extensive preparation before they can be analyzed by mass spectrometry, which can be time-consuming
and labor-intensive.
• Vacuum requirements:
• Mass spectrometers operate under high vacuum conditions, which adds to the complexity of the instrument.

12. MASS SPECTROMETER

13. • https://images.app.goo.gl/9ucH
• https://images.app.goo.gl/7m1u
• https://youtu.be/w3LS22E10Zc?si=z3aksI9OHQSGw8DG
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