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 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).
Thin-layer chromatography (TLC) is a chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography is performed on a sheet of glass, plastic, or aluminium foil, which is coated with a thin layer of adsorbent material, usually silica gel, aluminium oxide (alumina), or cellulose.
Usually, analysis is not considered an easy subject and it can't be understood on its own if you don't have some proper notes and clear concepts so I am here to help you in analysis for clearing few concepts on UV-Visible spectrophotometer, soon will come up with a new set of notes on new topic depending upon the response.
GEL CHROMATOGRAPHY
GEL CHROMATOGRAPHY B.PHARM
GEL CHROMATOGRAPHY M.PHARM
SIZE EXCLUSION CHROMATOGRPHY
GEL CHROMATOGRPHY PPT
GEL CHROMATOGRAPHY SLIDESHARE
Fluorimetry, principle, Concept of singlet,doublet,and triplet electronic sta...Vandana Devesh Sharma
Content-Principle
concept of singlet, doublet and triplet electronic stages,
Internal and external conversions,
Factors affecting fluorescence,
quenching,
Instrumentation and
applications
Types of luminescence including
bioluminescence,
chemiluminescence,
Fluorescence, and
phosphorescence
These various forms of luminescence differ in their method of emitting light.
Bioluminescence
Chemiluminescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds) Fluorimetry
An analytical technique for identifying and characterizing minute amounts of substance by excitation of the substance with a beam of ultraviolet/Visible light and detection and measurement of the characteristic wavelength of fluorescent light emitted.Excited – State Processes in molecules
Thin-layer chromatography (TLC) is a chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography is performed on a sheet of glass, plastic, or aluminium foil, which is coated with a thin layer of adsorbent material, usually silica gel, aluminium oxide (alumina), or cellulose.
Usually, analysis is not considered an easy subject and it can't be understood on its own if you don't have some proper notes and clear concepts so I am here to help you in analysis for clearing few concepts on UV-Visible spectrophotometer, soon will come up with a new set of notes on new topic depending upon the response.
GEL CHROMATOGRAPHY
GEL CHROMATOGRAPHY B.PHARM
GEL CHROMATOGRAPHY M.PHARM
SIZE EXCLUSION CHROMATOGRPHY
GEL CHROMATOGRPHY PPT
GEL CHROMATOGRAPHY SLIDESHARE
Fluorimetry, principle, Concept of singlet,doublet,and triplet electronic sta...Vandana Devesh Sharma
Content-Principle
concept of singlet, doublet and triplet electronic stages,
Internal and external conversions,
Factors affecting fluorescence,
quenching,
Instrumentation and
applications
Types of luminescence including
bioluminescence,
chemiluminescence,
Fluorescence, and
phosphorescence
These various forms of luminescence differ in their method of emitting light.
Bioluminescence
Chemiluminescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds)
Fluorescence starts immediately after the absorption of light and stops as soon as the incident light is cut off
Eg -The fluorescent clothes, shoes
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation
In fluorescence, absorption and emission light takes place in very short time (10-12 or 10-9 seconds) Fluorimetry
An analytical technique for identifying and characterizing minute amounts of substance by excitation of the substance with a beam of ultraviolet/Visible light and detection and measurement of the characteristic wavelength of fluorescent light emitted.Excited – State Processes in molecules
High performance liquid chromatography (HPLC), also known as high pressure liquid chromatography, is essentially a form of column chromatography in which the stationary phase consists of small particle packings (3-50 µm) contained in a column with a small bore (2-5 mm), one end of which is attached to a source of pressurised liquid eluant (mobile phase)
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
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Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
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Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
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micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
3. HPLC is a form of liquid chromatography used to separate compounds that are
dissolved in solution.
It is modified form of gas chromatography, it is applicable for both Volatile as well
as Non volatile compound.
It is having a high resolution and separation capacity.
HPLC is characterized by the use of high pressure to push a mobile phase solution
through a column of stationary phase allowing separation of complex mixtures
with high resolution.
HPLC instruments consist of a reservoir of mobile phase, a pump, an injector, a
separation column, and a detector.
INTRODUCTION
4. Principle is based on adsorption as well as partition chromatography
It is depending on the nature of stationary phase, if stationary phase is solid
principle is based on adsorption chromatography and if stationary phase is liquid
principle is based on partition chromatography.
The principle of separation in normal phase mode and reverse phase mode is
adsorption.
When a mixture of components are introduced into a HPLC column, they travel
according to their relative affinities towards the stationary phase.
The component which has more affinity towards the adsorbent, travels slower.
The component which has less affinity towards the stationary phase travels faster.
Since no 2 components have the same affinity towards the stationary phase, the
components are separated
PRINCIPLE
5. The Principle of HPLC also based on Van Deemter equation which relates the
efficiency of the chromatographic column to the particle size of the column,
molecular diffusion and thickness of stationary phase.
Van Deemter Equation
6. TYPES OF HPLC TECHNIQUES:
A. Based on modes of chromatography
1. Normal phase mode
2. Reverse phase mode
B. Based on principle of separation
1. Adsorption chromatography
2. Ion exchange chromatography
3. Size exclusion or Gel permeation chromatography
4. Affinity chromatography
5. Chiral phase chromatography
7. C. Based on elution technique
1. Isocratic separation
2. Gradient separation
D. Based on the scale of operation
1. Analytical HPLC
2. Preparative HPLC
E. Based on the type of analysis
1. Qualitative analysis
2. Quantitative analysis
8. 1. Solvent delivery system
2. Pumps
3. Sample injection system
4. Column
5. Detectors
6. Recorders and Integrators
INSTRUMENTATION
9.
10.
11. 1. SOLVENT DELIVERY SYSTEM
The solvents or mobile phases used must be passed through the column at high
pressure at about 1000 to 3000 psi. This is because as the particle size of
stationary phase is few μ (5-10μ), the resistance to the flow of solvent is high.
Hence such high pressure is recommended.
The choice of mobile phase is important in HPLC and the eluting power of the
mobile phase is determined by its overall polarity, the polarity of the stationary
phase and the nature of the sample components.
Mixing unit is used to mix the solvents in different proportions and pass through
the column.
There are 2 types of mixing units i.e. low pressure mixing chamber (uses He for
degassing) and high pressure mixing chamber.
Mixing of solvents is done either with a static mixer or a dynamic mixer.
12. SOLVENT/ MOBILE PHASE RESERVOIRS
Glass or stainless-steel containers capable of holding up to 1 liter mobile
phase (pure organic solvents or aqueous solutions of salts and buffers)
Inert to a variety of aqueous and non aqueous mobile phases.
Stainless steel should be avoided for use with solvents containing halide ions.
13. Several gases are soluble in organic solvents.
When solvents are pumped under high pressure, gas bubbles are formed which will
interfere with the separation process, steady base line and the shape of the peak.
Hence degassing of solvent is important.
Degassing is done to prevent formation of gas bubbles in the pump or detector
(Mobile phases are degassed by stirring of the mobile phase under vacuum,
sonication or sparing with helium gas)
The mobile phase are filtered to remove particulate matter that may clog the
system.
Tubing
Should be inert.
Have ability to withstand pressure.
Able to carry sufficient volume.
Solvent Degassing
14. Techniques of Solvent degassing
1. Vacuum filtration
It can remove air bubbles, but not always reliable and complete.
2. Helium purging
By passing Helium through solvent.
It is effective but expensive.
3. Ultrasonification
Converts high frequency to mechanical vibrations.
This causes the removal of air bubbles.
15. 2. PUMPS
The solvents or mobile phase must be passed through a column at high
pressures at up to 6000 psi which is done by pump.
As the particle size of stationary phase is smaller (5 to 10μ) the resistance to the
flow of solvent will be high.
That is, smaller the particle size of the stationary phase the greater is the
resistance to the flow of solvents hence, high pressure is recommended.
Requirements For Pumps
→ Generation of pressure of about 6000 psi.
→ Pulse free output & all materials in the pump should be chemically resistant to
solvents.
→ Flow rates ranging from 0.1 to 10 mL/min
→ Pumps should be capable of taking the solvent from a single reservoir or more
than one reservoir containing different solvents simultaneously.
16. TYPES OF PUMPS
1. Displacement Pumps
2. Reciprocating Pumps
3. Pneumatic Pumps
DISPLACEMENT PUMPS
It consists of large, syringe like chambers equipped with a plunger activated by
a screw driven mechanism powered by a stepping motor.
So it is also called as Screw Driven Syringe Type Pump.
Advantages:- It produces a flow that tends to be independent of viscosity &
back pressure.
Disadvantages:- It has a limited solvent capacity & considerably inconvenient
when solvents must be changed.
17. RECIPROCATING PUMPS
The term reciprocating describes any continuously repeated backward and
forward motion.
Advantages
Have small internal volume of 35-400μL
Higher output pressures up to 10,000 psi.
Adaptability to gradient elution.
Large solvent capacities & constant flow rates.
Largely independent of column back pressure & solvent viscosity.
Disadvantages
Produces a pulsed flow which is damped because pulses appear as baseline
noise on the chromatograph.
This can be overcome by use of dual pump heads or elliptical cams to minimize
such pulsations.
18. Solvent is pumped back and forth by a motor driven piston
Two ball check valves which open & close which controls the flow
The piston is in direct contact with the solvent
19. PNEUMATIC PUMPS
In this pumps, the mobile phase is driven through the column with the use of
pressure produced from a gas cylinder.
It has limited capacity of solvent.
Due to solvent viscosity back pressure may develop.
20. 3. SAMPLE INJECTION SYSTEM
Several injector devices are available either for manual or auto injection of the sample.
I. Septum Injector
These are used for injecting the sample through a rubber septum.
This kind of injectors cannot be commonly used, since the septum has to
withstand high pressures.
II. Stop Flow Injector
In this type, the flow of mobile phase is stopped for a while & the sample is
injected through a valve.
III. Rheodyne Injector
It is the most popular injector and is widely used.
This has a fixed volume of loop, for holding sample until its injected into the
column, like 20μL, 50μL or more.
The injector is positioned just before the inlet of the column.
Two modes: Load position (Sample is loaded in the loop) & Inject mode
21. 4. COLUMN
It is the Heart of chromatography.
General Specifications (Average range)
Length: 5 – 30 cm
Diameter: 2 mm – 50 mm
Particle size: 1 to 20 micron
Particle nature: Spherical, Uniform sized, porous materials are used.
Materials of construction for the tubing:
Stainless steel (Most popular, gives high pressure)
Glass (For biomolecules)
PEEK
Packing Material
Silica / Alumina particle / Ion exchange resins
22. TYPES OF COLUMN
1. Pre-column
It contains a packing chemically identical to that in analytical column.
Mainly used to remove the impurities from the solvent and thus prevents
contamination of the analytical column, it can protect analytical column.
It is also called as guard column or protective column.
It is having large particle size, short length of 2 to 10 cm, so does not affect
separation.
23. 2. Analytical column
The success or failure of analysis depends upon choice of column.
Actual separation is carried out here.
Stainless-steel tube
Size length: 25 to 100 cm
Internal diameter - 2 to 4.6 mm
Column is filled with small particles 5-10 micron. The solid support can be
silica gel, alumina.
The separation is result of different components adhering to or diffusion into
the packing particles when the mobile phase is forced through column.
25. C8 and C18 columns are considered as examples of reversed phase liquid
chromatography (RP).
The stationary phase here is seen as a thin film of non-polar liquid phase that
has been designed to be chemically similar to an inert material (Silica gel
particles).
The difference between the two columns will be in the length of the carbon-
chain attached to the silica surface.
Accordingly, C8 HPLC columns have packing material composed of silica
particles attached to C8 carbon units.
C18 will, of course, have packing materials coated with C18 hydrophobic units.
Categorically both are reversed phase but C18 columns will definitely be more
“hydrophobic” rather than the C8 columns.
26. 5. DETECTOR
Absorbance (UV/Vis and PDA)
Refractive index (detects the change in turbidity)
Fluorescence (if the analyte is fluorescent)
Electrochemical (measures current flowing through a pair of electrodes, on
which a potential difference is imposed, due to oxidation or reduction of solute)
Conductivity (for ions)
Mass spectrometry (HPLC-MS)
27. IDEAL PROPERTIES OF DETECTOR
High Sensitivity
Universality or predictable specificity
Large linear response range
Non-Destructive
Insensitive to temperature & mobile phase
Continuous operation
Reliable and easy to use
28. UV-VISIBLE DETECTOR
UV visible detector is widely used as it detects large number of compounds
because most drugs have appropriate structural characteristics for light
absorption.
These are useful for aromatic compounds and other type of unsaturated systems.
These are classified as fixed or variable wavelength detectors.
Fixed wavelength detectors employ filter as a source to provide appropriate
wavelength.
Most common fixed wavelength detectors are based on 254 nm.
Variable wavelength detectors are employ a spectrophotometer to provide
dispersion of light and selection of any wavelength in UV visible regions.
Diffraction gratings are frequently used for wavelength dispersion.
29. REFRACTIVE INDEX (RI) DETECTOR
Detection occurs when the light is bent due to samples eluting from the columns,
and this is read as a disparity b/w the two channels.
It is not much used for analytical applications because of low sensitivity &
specificity.
When a solute is in the sample compartment, refractive index changes will shift
the light beam from the detector.
30. PHOTODIODE ARRAY (PDA)
A PDA is a linear array of photodiodes on an integrated circuit (IC) chip which
detect the sample when it passes through column.
It can measure entire wavelength range in real time.
It can collect spectra of each peak and calculate the lambda max, it can monitor a
sample at more than one wavelength.
This allows for the analysis of wide range of compounds in the sample.
This is especially useful when wavelength maxima of the analytes are different.
The resulting spectra is 3 dimensional plot of Response vs Time vs Wavelength.
Sometimes called as diode array detector (DAD)
31. FLUORIMETRIC DETECTOR
It is based on the fluorescent radiation emitted by some compounds.
It measures light emission from excited atoms in an analyte.
More sensitive and specific.
The disadvantage is that most compounds are not fluorescent in nature.
Fluorescence is a type of luminescence in which the light energy is released in
the form of a photon in nanoseconds to microseconds.
32. 6. RECORDERS AND INTEGRATORS
Recorders are used to record responses obtained from the detectors after
amplification, if necessary.
They record the baseline & all the peaks obtained with respect to time.
Retention time can be found out from this recordings, but area under curve
cannot be determined.
The Integrators are improved versions of recorders with some data processing
capabilities.
They can record the individual peaks with retention time, height, width of peaks,
peak area, percentage area, etc.
Integrators provides more information on peaks than recorders.
In recent days computers and printers are used for recording and processing the
obtained data & for controlling several operations.
33. Drug Discovery
→ Clinical Analysis
→ Proteomics
Forensic Chemistry
→ Drug Metabolism study
→ Environmental chemistry
Diagnostic studies
Cosmetic analysis
→ Determination of Green Florescent Protein
→ Structural Determination
Pharmaceutical Applications
→ Identification of Bile Acid Metabolite
→ Clinical Applications
Biochemical Genetics
→ Qualitative and quantitative analysis
→ Therapeutic Drug Monitoring
APPLICATIONS