It is also known as vaccume chromatography.
It is one of the type of oldest technique.
It is modified from of flash chromatography.
It is column chromatography technique, principle is based on partition chromatography.
It is also known as medium phase chromatography.
It can consist of stationary phase and mobile phase. It is important for separation, identification, purification of compound.
It is a glass liquid phase chromatographic technique.
It is modified from of flash chromatography.
It is used for the separation of plant pigments and metabolites.
It is used as qualitative analysis and quantitative analysis.
It is also known as vaccume chromatography.
It is one of the type of oldest technique.
It is modified from of flash chromatography.
It is column chromatography technique, principle is based on partition chromatography.
It is also known as medium phase chromatography.
It can consist of stationary phase and mobile phase. It is important for separation, identification, purification of compound.
It is a glass liquid phase chromatographic technique.
It is modified from of flash chromatography.
It is used for the separation of plant pigments and metabolites.
It is used as qualitative analysis and quantitative analysis.
High Performance Liquid Chromatography (HPLC) is a form of column chromatography that pumps a sample mixture or analyte in a solvent (known as the mobile phase) at high pressure through a column with chromatographic packing material (stationary phase).
High-performance liquid chromatography (HPLC), is a technique in analytical chemistry used to separate, identify, and quantify individual components from a mixture.
Content include basic introduction to chromatography. Brief view of Liquid Chromatography. HPLC introduction, other names, types of HPLC, detailed instrumentation with image of each part, and applications. Sources of content described in 'References' entitled slide. This presentation was prepared for the partial fulfillment of Master of Pharmacy.
HPLC- introduction, principle, types, working, instrumentation and operations of HPLC has been included with appropriate gifs and images for better understanding. What are all the things need to be known by a science student about HPLC (basics and working) is clearly given in this presentation.
High Performance Liquid Chromatography (HPLC) is a form of column chromatography that pumps a sample mixture or analyte in a solvent (known as the mobile phase) at high pressure through a column with chromatographic packing material (stationary phase).
High-performance liquid chromatography (HPLC), is a technique in analytical chemistry used to separate, identify, and quantify individual components from a mixture.
Content include basic introduction to chromatography. Brief view of Liquid Chromatography. HPLC introduction, other names, types of HPLC, detailed instrumentation with image of each part, and applications. Sources of content described in 'References' entitled slide. This presentation was prepared for the partial fulfillment of Master of Pharmacy.
HPLC- introduction, principle, types, working, instrumentation and operations of HPLC has been included with appropriate gifs and images for better understanding. What are all the things need to be known by a science student about HPLC (basics and working) is clearly given in this presentation.
Supercritical fluid chromatography| chromatographic techniques| by Gobind KumarGobindKumar25
hi this is most helpful for those who study supercritical fluid chromatography. it explain very easily and briefly. all data taken from several books, google research and research articles.Supercritical fluid chromatography (SFC) is a form of normal phase chromatography that uses a supercritical fluid such as carbon dioxide as the mobile phase.[1][2] It is used for the analysis and purification of low to moderate molecular weight, thermally labile molecules and can also be used for the separation of chiral compounds. Principles are similar to those of high performance liquid chromatography (HPLC), however SFC typically utilizes carbon dioxide as the mobile phase; therefore the entire chromatographic flow path must be pressurized. Because the supercritical phase represents a state in which liquid and gas properties converge, supercritical fluid chromatography is sometimes called convergence chromatography.
fluid chromatography (SFC) can be used on an analytical
scale.
It is a combination of High performance liquid chromatography (HPLC)
and Gas chromatography (GC).
It can be used with non-volatile and thermally labile analytes.
It can be used with the universal flame ionization detector.
It is important to producing narrower peaks due to rapid diffusion.
It is important for the chiral separations and analysis of high-molecularweight
hydrocarbons.
Supercritical fluids are suitable as a substitute for organic solvents in a
range of industrial and laboratory processes.
HPLC- Introduction, Theory, Instrumentation, Advantage, Applications
High-performance liquid chromatography or commonly known as HPLC, is an analytical technique used to separate, identify or quantify each component in a mixture.
The mixture is separated using the basic principle of column chromatography and then identified and quantified by spectroscopy.
In the 1960s, the column chromatography LC with its low-pressure suitable glass columns was further developed to the HPLC with its high-pressure adapted metal columns.
HPLC is thus basically a highly improved form of column liquid chromatography. Instead of a solvent being allowed to drip through a column under gravity, Solvent is forced through under high pressures of up to 400 atmospheres.
Principle
The separation principle of HPLC is based on the distribution of the analyte (sample) between a mobile phase (eluent) and a stationary phase (packing material of the column). Depending on the chemical structure of the analyte, the molecules are retarded while passing the stationary phase.
Instrumentation
1.Solvent reservoir and degassing system
2. Pumping System (Screw- driven syringe pump, Reciprocating pump, Pneumatic or constant- pressure pump)
3. Sample injection system(Septum injectors, Stop flow septum- less injection, Micro- volume sampling valves)
4. Columns- (1. Guard columns 2.separating column)
5. Detectors( The commonly used detectors in HPLC are
Bulk property detectors- examples
1. Refractive-index detectors
2. Conductivity detectors
Solute property detectors- Examples
1. UV detectors
2. Fluorescence detectors
Multipurpose detectors- Example-
1. Perkin-Elmer 3D system (UV absorption+ fluorescence + conductometric detection altogethers)
Electrochemical Detectors- Examples
1.Amperometric, 2. Coulometric detectors)
6. Recorder( There are various types of data processors; from a simple system consisting of the in-built printer and word processor while those with software that are specifically designed for an LC system which not only data acquisition but features, like peak-fitting baseline correction, automatic concentration calculation, molecular weight determination, etc.) Type of HPLC- Normal phase, Reverse Phase, ion exchange, size exclusion, Applications-Stability study- eg Atropin
Bioassays- HPLC is commonly used for the bioassay and analysis of peptide harmones and some antibiotics- cotrimoxazole, penicillins, sulphates and chloramphenicol
In cosmetic industries- used for analyzing the quality of various cosmetic products such as lipsticks, gels, creams etc
Isolation of Natural pharmaceutically Active Compounds– use in the isolation of different type of Alkaloids and Glycosides ( analysis of cinchona, liquorice, ergot extracts and digitalis.)
Control of microbiological processes- HPLC is used in analyse antibiotics (eg. Tetracyclines, chloramphenicol, strptomycin and penicillins )
Assay of cephalosporins
Advantage, Limitation
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
3. In SFC, the sample is carried through a separating
column by a supercritical fluid where the mixture is
divided into unique bands based on the amount of
interaction between the individual analytes and the
stationary phase in the coumn. As these bands
leave the column their identities and quantities are
determined by a detector
Supercritical Fluids
Supercritical temperature :For every substance
there is a temperature above which it can no longer
exist as a liquid, no matter how much pressure is
applied.
Supercritical pressure : For every substance
there is a pressure above which the substance can
no longer exist as a gas, no matter how high the
temperature is raised.
5. Theory :
Part of the theory of separation in SFC is
based on the density of the supercritical fluid which
corresponds to solvating power. As the pressure in
the system is increased, the supercritical fluid
density increases and correspondingly its solvating
power increases. Therefor, as the density of the
supercritical fluid mobile phase is increased,
components retained in the column can be made to
elute. This is similar to temperature programming in
GC or using a solvent gradient in HPLC.
7. Mobile phase:
There are a number of possible fluids which may be
used in SFC as the mobile phase. Mostly CO2 is
used.
The main disadvantage of carbon dioxide is its inability
to elute very polar or ionic compounds.
This can be overcome by adding a small portion of a
second fluid called a Modifier fluid. (alcohols, cyclic
ethers, acetonitrile and chloroform)
The addition of the modifier fluid improves the solvating
ability of the supercritcal fluid and sometimes
enhances selectivity of the separation.
8. Stationary Phase
Same as those for GC and LC, with some modification.
Silica/Alumina
Useful for non-polar compounds
Lead to irreversible adsorption of some polar solutes
Widely used polar Stationary Phase are
Polysiloxanes:- stable, flexible Si--O bond lead to good
diffusion.
Substituted with chemical groups for selective
interaction with analyte
Polymethylsiloxanes:- increase efficiency in separating
closely related polar analytes
Cyanopropyl polysiloxanes:-useful for compounds with -
COOH
9. Pumps
In contract to HPLC pumping system, pressure rather
than flow control is necessary and pulseless
operation is more critical.
In general, the type of high-pressure pump used in
SFC is determined by the column type.
For packed columns, reciprocating pumps are
generally used,
while for capillary SFC syringe pumps are most
commonly employed.
Reciprocating pumps allow easier mixing of the
mobile phase or introduction of modifier fluids.
Syringe pumps provide consistent pressure for a neat
mobile phase
10. Injector
Injection in SFC is usually achieved by switching of the
content of a sample loop into the carrier fluid at the
column entrance by means of a suitable valve. For
packed column SFC, a conventional HPLC injection
system is adequate, but for the capillary column SFC,
the sample volume depends on column diameters and
small sample volumes must be quickly injected into the
column, therefore pneumatically driven valves are used.
Injector Volumes
Open tubular columns
Injection volumes >96nL
Greater volume affects resolution
Packed columns
Injection volumes >1uL
11. Types of Injectors
a. Loop injection is a direct transposition of what is
applied in analytical SFC. A low pressure feed
pump is used to fill the loop. This is mostly
recommended for preliminary tests of column
performance and elution parameters.
12. b. An “in-line” injection mode is more versatile:
the system offers a better flexibility for changing the
injected volume. A high-pressure pump is required
to inject the feed solution, but the injected stream is
dissolved in the eluent flow.
c. The “in-column” injection mode is an
alternative which permits injection of the feed
solution directly onto the column, without any
dilution
13. Oven
A thermostated column oven is required for precise temperature
control of the mobile phase. Conventional GC or LC ovens are
generally used.
Columns
Once the sample is injected into the supercritical stream it is
carried into the analytical column. The column contains a
highly viscous liquid (called a stationary phase) into which the
analytes can be temporarily adsorbed and then released
based on their chemical nature. This temporary retention
causes some analytes to remain longer in the column and is
what allows the separation of the mixture. Different types of
stationary phases are available with varying compositions and
polarities.
There are two types of analytical columns used in SFC,
A). Packed columns contain small deactivated particals
to which the stationary phases adhears. The columns are
conventionally stainless steel.
B). Capillary columns are open tubular columns of
narrow internal diameter made of fused silica, with the
stationary phase bonded to the wall of the column.
14. Detectors
SFC is compatible with both HPLC and GC detectors.
As a result, optical detectors, flame detectors, and
spectroscopic detectors can be used. However, the
mobile phase composition, column type, and flow
rate must be taken into account when the detector
is selected as they will determine which detector is
able to be used. Some care must also be taken
such that the detector components are capable of
withstanding the high pressures of SFC.
16. In SFC the mobile phase is initially pumped as a
liquid and is brought into the supercritical region by
heating it above its supercritical temperature before
it enters the analytical column. It passes through an
injection valve where the sample is introduced into
the supercritcal stream and then into the analytical
column. It is maintained supercritical as it passes
through the column and into the detector by a
pressure restrictor placed either after the detector
or at the end of the column. The restrictor is a vital
component as it keeps the mobile phase
supercritical throughout the separation and often
must be heated to prevent colgging; both variable
and fixed restrictors are available.
17. SFC Advantages
Supercritical fluid chromatography has several main
advantages over other conventional chromatographic
techniques (GC and HPLC).
Compared with HPLC, SFC provides rapid separations
without the use of organic solvents. With the desire for
environmentally conscious technology, the use of organic
chemicals as used in HPLC could be reduced with the use of
SFC. Because SFC generally uses carbon dioxide collected
as a byproduct of other chemical reactions or is collected
directly from the atmosphere, it contributes no new chemicals
to the environment. In addition, SFC separations can be done
faster than HPLC separations because the diffusion of solutes
in supercritical fluids is about ten times greater than that in
liquids (and about three times less than in gases). This results
in a decrease in resistance to mass transfer in the column and
allows for fast high resolution separations.
18. Compared with GC, capillary SFC can provide high
resolution chromatography at much lower
temperatures. This allows fast analysis of
thermolabile compounds.
Finally SCF have the advantage of higher diffusion
constants and lower viscosities relative to liquid
solvents. The low viscosity means that pressure
drop across the column for a given flow rate is
greatly reduced. The greater diffusibility means
longer column length can be used. Higher diffusion
coefficient means higher analysis speed that
increases in the order HPLC, SFC and GC. These
advantages are important in both, chromatography
and extractions with SCFs.
19. Applications
SFC finds use in industry primarily for separation of chiral
molecules, and uses the same columns as standard HPLC
systems. SFC is now commonly used for achiral separations
and purifications in the pharmaceutical industry
Fossil Fuels and Hydrocarbons
Agrichemicals
Drugs and Pharmaceuticals
Polymers
Explosives and Propellants
Lipids
Carbohydrates
Industrial Chemicals
Foods and Flavors
Natural Products
Metal Chelates and Organometallic Compounds
Enantiomers