- GC-MS and LC-MS are hyphenated analytical techniques that combine gas or liquid chromatography with mass spectrometry to separate and identify compounds in mixtures. In GC-MS, compounds are vaporized and separated by a gas chromatograph before being ionized and detected by mass spectrometry. In LC-MS, compounds are separated by liquid chromatography and then ionized, fragmented, and detected by mass spectrometry to determine molecular structure. These techniques are used in applications like environmental analysis, forensics, metabolomics, and pharmaceutical analysis.
• It is the combination of liquid chromatography and the mass spectrometry.
• Liquid chromatography-mass spectrometry (LC-MS) is an analytical chemistry
technique that combines the physical separation capabilities of liquid
chromatography with the mass analysis capabilities of mass spectrometry.
• The combination of these two powerful techniques gives the chemical analyst the
ability to analyze virtually any molecular species; including, thermally labile, non
volatile, and high molecular weight species.
GCMS & LCMS
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Sub :- Advanced Analytical Techniques
M.Pharmacy Sem1
Savitribai Phule Pune University
Contents :-
GC-MS
Introduction
Principle
Instrumentation
Application
LC-MS
Introduction
Principle
Instrumentation
Application
Introduction to Gas chromatography-Mass spectroscopy
Gas chromatography-Mass spectroscopy is one of the so-called hyphenated analytical techniques. It is actually two techniques that are combined to form a single method of analyzing mixtures of chemicals
GC-MS is an instrumental technique, comprising a gas chromatograph coupled to a mass spectrometer by which complex mixtures of chemicals may be separated, identified & quantified. In order to a compound to be analysed by GC-MS it must be sufficiently volatile & thermally stable.
Principle :-
The Sample solution is injected into the GC inlet where it is vapourized & swept onto a chromatographic column by the carrier gas ( usually helium). The sample flows through the column & compounds comprising the mixture of interest are separated by virtue of their relative interaction with the coating of the column (stationery phase) & the carrier gas (mobile phase). The later part of the column passes through a heated transfer line & ends at the entrance to ion source where compounds eluting from the column are converted to ions
Mass Analyzers for example Magnetic Sector Mass Analyzer, Double Focusing Mass Analyzer, Quadroupole Mass Analyzer, Time of Flight Mass Analyzer and Applications of Mass Analyzer were explained
• It is the combination of liquid chromatography and the mass spectrometry.
• Liquid chromatography-mass spectrometry (LC-MS) is an analytical chemistry
technique that combines the physical separation capabilities of liquid
chromatography with the mass analysis capabilities of mass spectrometry.
• The combination of these two powerful techniques gives the chemical analyst the
ability to analyze virtually any molecular species; including, thermally labile, non
volatile, and high molecular weight species.
GCMS & LCMS
htps://youtube.com/vishalshelke99
https://instagram.com/vishal_stagram
Sub :- Advanced Analytical Techniques
M.Pharmacy Sem1
Savitribai Phule Pune University
Contents :-
GC-MS
Introduction
Principle
Instrumentation
Application
LC-MS
Introduction
Principle
Instrumentation
Application
Introduction to Gas chromatography-Mass spectroscopy
Gas chromatography-Mass spectroscopy is one of the so-called hyphenated analytical techniques. It is actually two techniques that are combined to form a single method of analyzing mixtures of chemicals
GC-MS is an instrumental technique, comprising a gas chromatograph coupled to a mass spectrometer by which complex mixtures of chemicals may be separated, identified & quantified. In order to a compound to be analysed by GC-MS it must be sufficiently volatile & thermally stable.
Principle :-
The Sample solution is injected into the GC inlet where it is vapourized & swept onto a chromatographic column by the carrier gas ( usually helium). The sample flows through the column & compounds comprising the mixture of interest are separated by virtue of their relative interaction with the coating of the column (stationery phase) & the carrier gas (mobile phase). The later part of the column passes through a heated transfer line & ends at the entrance to ion source where compounds eluting from the column are converted to ions
Mass Analyzers for example Magnetic Sector Mass Analyzer, Double Focusing Mass Analyzer, Quadroupole Mass Analyzer, Time of Flight Mass Analyzer and Applications of Mass Analyzer were explained
Gas chromatography head points:
Invention of Chromatography
original chromatography Experiment
Common types of chromatography
Paper and Thin layer chromatography
How does chromatography work?
Theoretical Plate
gas chromatography
schematic of GC
carrier gas-supply
Injection port
sample Injection system
split/spitless Injection
sample valves
GC columns
open tubular columns
Temperature Control
Solid Support Materials
Particle size of Supports
The stationary Phase
Detection systems
Characteristics of the Ideal Detector
Flame Ionization Detectors
Thermal Conductivity Detector
Electron-capture Detectors
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The aim of the coupling is to obtain an information-rich detection for both identification and quantification compared to that with a single analytical technique.
Atomic absorption spectroscopy, History, atomization techniques, and instrume...Muhammad Asif Shaheeen
History, principle, types, instrumentation, comparison with atomic emission spectroscopy, interference, advantages and disadvantages of different types of atomization techniques.
Gas chromatography head points:
Invention of Chromatography
original chromatography Experiment
Common types of chromatography
Paper and Thin layer chromatography
How does chromatography work?
Theoretical Plate
gas chromatography
schematic of GC
carrier gas-supply
Injection port
sample Injection system
split/spitless Injection
sample valves
GC columns
open tubular columns
Temperature Control
Solid Support Materials
Particle size of Supports
The stationary Phase
Detection systems
Characteristics of the Ideal Detector
Flame Ionization Detectors
Thermal Conductivity Detector
Electron-capture Detectors
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
The aim of the coupling is to obtain an information-rich detection for both identification and quantification compared to that with a single analytical technique.
Atomic absorption spectroscopy, History, atomization techniques, and instrume...Muhammad Asif Shaheeen
History, principle, types, instrumentation, comparison with atomic emission spectroscopy, interference, advantages and disadvantages of different types of atomization techniques.
Gas chromatography–mass spectrometry (GC-MS) is an analytical method that combines the features of gas-chromatography and mass spectrometry to identify different substances within a test sample.[1] Applications of GC-MS include drug detection, fire investigation, environmental analysis, explosives investigation, food and flavor analysis, and identification of unknown samples, including that of material samples obtained from planet Mars during probe missions as early as the 1970s. GC-MS can also be used in airport security to detect substances in luggage or on human beings. Additionally, it can identify trace elements in materials that were previously thought to have disintegrated beyond identification. Like liquid chromatography–mass spectrometry, it allows analysis and detection even of tiny amounts of a substance.[2]
GC-MS has been regarded as a "gold standard" for forensic substance identification because it is used to perform a 100% specific test, which positively identifies the presence of a particular substance. A nonspecific test merely indicates that any of several in a category of substances is present. Although a nonspecific test could statistically suggest the identity of the substance, this could lead to false positive identification. However, the high temperatures (300°C) used in the GC-MS injection port (and oven) can result in thermal degradation of injected molecules,[3] thus resulting in the measurement of degradation products instead of the actual molecule(s) of interest.The first on-line coupling of gas chromatography to a mass spectrometer was reported in the late 1950s.[4][5] An interest in coupling the methods had been suggested as early as December 1954.
Gas chromatography-Mass spectrometry (GC-MS)Saira Fatima
PRESENTED BY
SAIRA FATIMA
SABAHAT MEHMOOD
SANA USMAN
MSc 4 (2018-2020)
Department of MicroBiology & Molecular Genetics
University of the Punjab
Lahore, Pakistan
LC/MS is a technique that combines physical separation capabilities of LC with mass analysis capability of MS.
It is a method that combines separation power of HPLC with detection power of MS.
In LC-MS we remove the detector from the column of LC and fit the column to interface of MS.
In the most of the cases the interface used in LC-MS are ionization source.
GAS CHROMATOGRAPHY-MASS SPECTROSCOPY [GC-MS]Shikha Popali
THIS PRESENTATION GIVES A DETAIL ACCOUNT ON THE GC-MS WITH ITS INTRODUCTION, BASIC PRINCIPLE OF BOTH COMBINED AND INDIVIDUALLY WITH ITS INSTRUMENTATION, APPLICATION AND EXAMPLES, MAKES EASY TO COLLECT ALL THE DATA AT A PLACE ACCORDING TO THE M.PHARM SYLLABUS S PER PCI
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
3. Introduction to Gas chromatography-Mass spectroscopy
Gas chromatography-Mass spectroscopy is one of the so-
called hyphenated analytical techniques. It is actually two
techniques that are combined to form a single method of
analyzing mixtures of chemicals
GC-MS is an instrumental technique, comprising a
gas chromatograph coupled to a mass spectrometer by
which complex mixtures of chemicals may be separated,
identified & quantified. In order to a compound to be
analysed by GC-MS it must be sufficiently volatile &
thermally stable.
4. Principle :-
The Sample solution is injected into the GC inlet where it is
vapourized & swept onto a chromatographic column by the carrier
gas ( usually helium). The sample flows through the column &
compounds comprising the mixture of interest are separated by
virtue of their relative interaction with the coating of the column
(stationery phase) & the carrier gas (mobile phase). The later part
of the column passes through a heated transfer line & ends at the
entrance to ion source where compounds eluting from the column
are converted to ions
6. 1 ] Carrier Gas :-
• It is served as a mobile phase supplied in the steel tank under high
pressure.
• At a pressure of 40-80 psi passes into flow controllers. which allows
the operator to adjust the flow rate.
• Usually nitrogen & helium are used.
• And occasionally hydrogen & argon used.
• It should be inert with respect to sample component.
2] Sample Injection Port :-
• It is small chamber slightly above to the column
• In this the sample is made to vapourize rapidly before entering to
column.
• Sample is introduced int flowing gas through a sealing rubber using
a microlitre syringe
7. 3] Column :- Two Types of column Capillary Column & Packed
Column
Capillary Column :-
• It consist of long capillary tubing 30-90M in length.
• It is made up from stainless steel & coil
• For fast analysis shorter column are applied.
• Large columns are required for high resolution seperation.
Packed Column :-
• These columns, less commonly used today, have diameter of 1.6 to
9.5mm and a length of between 1–3m.
• Manufactured from steel or glass, the internal wall of the tube is
treated to avoid catalytic effects with the sample.
• They can withstand a carrier gas flow rate within the range 10–40
mL/min.
8. Jet Separator :-
• Two capillary tubes aligned with a small space between them. (1
mm)
• A vacuum is created between the two tubes using a rotary pump.
• The GC effluent enters the vacuum region, those molecules which
continue in the same direction enter the second capillary tube and
continue to the ion source.
• The carrier gas molecules are more easily diverted from the linear
path by collisions.
• The analyte molecules are much larger and carry more momentum.
• The surface of the separator must be inactive and a reasonably even
temperature
9. • The gas chromatograph utilizes a capillary column which
depends on the column’s dimension ( length, diameter, film
thickness ) as well as the phase properties.
• The difference in the chemical properties between molecules
in a mixture & their relative affinity for the stationery phase of
the column will promote separation of the molecules as the
sample travels the length of the column.
• The molecules take different amounts of time to come out of
(elute from) the gas chromatograph, and this allows the mass
spectrometer downstream to capture, ionize, accelerate,
deflect, and detect the ionized molecules separately.
• The mass spectrometer does this by breaking each molecule
into ionized fragments and detecting these fragments using
their mass to charge ratio.
10. Ionization :-
After the molecules travel the length of the column, pass
through the transfer line and enter into the mass
spectrometer they are ionized by various methods with
typically only one method being used at any given time. Once
the sample is fragmented it will then be detected, usually by
an electron multiplier diode, which essentially turns the
ionized mass fragment into an electrical signal that is then
detected.
1] Electron Ionization
2] Chemical Ionization
11. 1] Electron Ionization :-
The molecules enter into the MS where they are
bombarded with free electrons emitted from a filament, not
unlike the filament one would find in a standard light bulb.
The electrons bombard the molecules, causing the molecule
to fragment in a characteristic and reproducible way.
2] Chemical Ionization :-
a reagent gas,typically methane or ammonia is
introduced into the mass spectrometer. Depending on the
technique (positive CI or negative CI) chosen, this reagent gas
will interact with the electrons and analyte and cause a 'soft'
ionization of the molecule of interest. A softer ionization
fragments the molecule to a lower degree..
13. • It consists of 4 voltage carrying rods.
• The ions are pass from one end to another end
• During this apply the radiofrequency and voltage complex
oscillations will takes place.
• Here the single positive charge ions shows the stable
oscillation and the remaining the shows the unstable
oscillations
• Mass scanning is carried out by varying each of the rf and
• voltage frequencies ratios keeping their ratios constant.
• Quadrupole ion storage (ion trap)
• It store the unsorted ions temporarily, they released to the
• detector by scanning the electric field.
14. Time of Flight Analyzer :-
In this type of analyzer the sorting of ions is done in
absence of magnetic field.
The ions produced are acquiring different velocities
depending on their masses
Here the particles reach the detector in the order of
the increasing order of their masses
Here electron multiplier detector is used. The
resolution power of this is 500-600
15. Ion Trap Analyzer :-
The ion trap mass analyser operates by similar principles where
it consists of circular ring electrode
Plus two end caps that form a chamber. Here AC or DC power along
RF potential is applied between the cups and the ring electrode.
There the ions entering into the chamber are trapped by
electromagnetic fields and they oscillates in concentric trajectories.
This process is called resonant ejection.
.
16. Applications :-
Environmental monitoring and cleanup -
GC-MS is becoming the tool of choice for tracking organic
pollutants in the environment.
Criminal forensics -
GC-MS can analyze the particles from a human body in order to
help link a criminal to a crime. GC-MS is increasingly used for
detection of illegal narcotics
Chemical engineering -
GC-MS is used for the analysis of unknown organic compound
mixtures. One critical use of this technology is the use of GC-MS
to determine the composition of bio-oils processed from raw
biomass.
17. • It is used in metabolite profiling, toxicity assessment or
toxclogy. e.g. a specific lesion inliver or kidney can be
prolifiled.
• Used in detection of lipophilic compounds in diverse plant
tissues.
• Analysis off biologically important aromatic amines.
• Identification of volatile components.
• For the determination of pyrethroid residues in vegetable
samples.
• Analysis of Pesticides in Foodstuffs.
18. Liquid Chromatography-Mass Spectroscopy :-
It is the combination of liquid chromatography and the mass
spectrometry.
In LC-MS we are removing the detector from the column of LC and
fitting the column to interface of MS.
Principle :-
19. The LC-MS technology involves use of an HPLC, wherein the
individual components in a mixture are first separated followed by
ionization and separation of the ions on the basis of their mass/charge
ratio. The separated ions are then directed to a photo or electron
multiplier tube detector, which identifies and quantifies each ion. The
ion source is an important component in any MS analysis, as this
basically aids in efficient generation of ions for analysis. To ionize
intact molecules, the ion source could be APCI (Atmospheric Pressure
Chemical Ionization), ESI (Electronspray Ionization), etc.
20. Column & Sample Preparation :-
The mobile phase is the solvent that moves the solute through out
column
Most widely used columns for LC-MS are:-
fast LC column. the use of short column. (15-50mm)
Micro LC column. the use of large column. ( 20-150mm)
• Sample preparation generally consists of concentrating the
analyte and removing compounds that can cause background ion
or suppress ionization.
Example of sample preparation include:-
1. On Column concentration - to increase analyte concentration.
2. Desalting – to reduce the sodium and potassium adduct formation
that commonly occurs in electro spray.
3. Filtration – to separate a low molecular-weight drug from proteins
in plasma, milk, or tissue.
21. Interfaces :-
It can connect the LC to MS
• It is difficult to interface a liquid chromatography
to a mass spectrometer cause of the necessity to
remove the solvent.
The commonly used interfaces are:-
1. Electrospray ionization (ESI)
2. Thermospray ionization (TSI)
3. Atmospheric pressure chemical ionization (APCI)
4. Atmospheric pressure photoionization(APPI)
22. Electro Spray Ionization (ESI) :-
• ESI draws sample solutions to the tip of a capillary tube,
where it applies a high voltage of about 3 to 5 kV.
• A nebulizer gas flows from outside the capillary to spray the
sample. This creates a fine mist of charged droplets with the
same polarity as the applied voltage.
• As these charged particles move, the solvent continues to
evaporate, thereby increasing the electric field on the droplet
surface. When the mutual repulsive force of the charges
exceeds the liquid surface tension, then fission occurs.
• As this evaporation and fission cycle is repeated, the droplets
eventually become small enough that the sample ions are
liberated into the gas phase
• ESI provides the softest ionization method available, which
means it can be used for highly polar, least volatile, or
thermally unstable compounds.
23. Atmospheric pressure chemical ionization (APCI)
• APCI vaporizes solvent and sample molecules by spraying the
sample solution into a heater (heated to about 400 C) using a
gas, such as N2.
• Solvent molecules are ionized by corona discharge to generate
stable reaction ions.
24. They are of 2 type:
a) Real-TSP ionization
b) Discharge electrode for external ionization and repeller
electrode
Thermospray ionization (TSI)
25. Atmospheric pressure photoionization(APPI) :-
The LC eluent is vaporized using a heater at atmospheric
pressure. The resulting gas is made to pass through a beam of
photons generated by a discharge lamp (UV lamp) which ionizes
the gas molecules.
26. Detectors :-
1] Photo graphic Plates
2] Faraday Cup
3] Electron multipliers
Photo graphic plates:
It is used as it is capable of higher resolution and speeder
than electronic devices. i.e. it can detect ions of all the masses
and provide a reverse geometry analyzer.
27. Faraday Cup
It is a metal cup into which all the ions are directed and the
signal produced is very stable and reproducible. It is used on
spectrometers where quantitative data is very important.
Electron multipliers
In this the current can be measured so accurately by just one ion
strikes the detector can be measured i.e. when an ion strikes the
surface of electron multiplier two electron are ejected. This
process continues until the end of electro multiplier end is
reached and electric current is analyzed and recorded with
electron multiplier surface.
28. Applications of LC-MS :-
• Molecular weight determination
• Determining the molecular weight of green fluorescent proteins
• Structural determination e.g. structural determination of
ginsenoside.
• Pharmaceutical Applications:
Rapid chromatography of benzodiazepines, Identification
of bile acid metabolite
• Biochemical Applications:
Rapid protein identification using capillaryLC/MS and
Database searching.
• Clinical Applications:
High-sensitivity detection of trimipramine and thioridazine
29. Reference :-
• G. C. Stafford et al.; International Journal of Mass
Spectrometry and Ion Processes
• Instrumental Methods of Analysis – By Gurdeep Chatwal
• Gas Chromatography Mass Spectroscopy (GC-MS)
(http://www.bris.ac.uk/nerclsmsf/techniques/gcms.html)
• www.enotes.com/topic/Liquid_chromatography-
mass_spectrometry
• www.impactanalytical.com/lc-ms-analysis.asp
• Wikipedia
30. Also available on Youtube!
Youtube :- https://youtube.com/vishalshelke99
Instagram :- https://instagram.com/vishal_stagram