This document discusses supercritical fluid chromatography (SFC). SFC uses supercritical fluids like carbon dioxide as the mobile phase. Carbon dioxide is most widely used as it is non-toxic, inexpensive, and has a critical temperature and pressure that are easily reached. SFC works on the principles of adsorption and partition chromatography. It can be used to analyze and purify low to moderate weight compounds, including chiral separations. SFC instrumentation includes pumps to deliver the mobile phase, an oven for temperature control, various injectors, columns, a backpressure regulator, and detectors. SFC finds applications in fields like pharmaceuticals and has advantages over HPLC like using less toxic solvents.
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.
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.
A presentation on column efficiency parameters in chromatography.. A part of gas chromatography in pharmacutical analysis..will be helpful for all mphrm students
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).
Detectors are the brain of any chromatograhic system. It help us to record the chromatogram based on certain characteristics of the analyte and help us in identifying that compound both qualitatively and quantitatively.
HPLC[ HIGH PERPROMANCE LIQUID CHROMATOGRAPHY OR HIGH PRESSURE LIQUID CHROMAT...Dr. Ravi Sankar
GASSCHROMATOGRAPHY[GC], ADVANCED STUDY OF THE FOLLOWING AND THEIR APPLICATIONS, INTRODUCTION, THEORY, COLUMN OPERATION,INSTRUMENTATION AND DETECTION,APPLICATIONS AND ADVANTAGES OF GC,PRINCIPLE OF SEPARATION IN GC, HOW GC MECHINE WORKS? COLUMN, DETECTORS.
BY P.RAVISANKAR, VIGNAN PHARMACY COLLEGE, VADLAMUDI, GUNTUR, A.P, INDIA.
Supercritical fluid extraction and Supercritical fluid chromatography are techniques which use supercritical fluids as solvent for both extraction and separation respectively.
The properties such as density, viscosity and diffusion constant of the supercritical fluids are intermediate between those of a substance in gaseous and liquid state.
This helps in efficient extraction and chromatographic separation compared to other techniques.
Optimum performance laminar chromatography (OPLC) is a pumped flow chromatography techniques that combine the user – friendly interface of HPLC with the capacity of flash chromatography and multidimensionally of TLC .
Optimum performance laminar chromatography (OPLC ) , in a contrast , is a pumped flow chromatography system that uses a planar 2D column format .
The multidimensionally capacity of OPLC is not limited to the separation technique alone , but also to the multitude of sample application and detection methods that are available .
A presentation on column efficiency parameters in chromatography.. A part of gas chromatography in pharmacutical analysis..will be helpful for all mphrm students
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).
Detectors are the brain of any chromatograhic system. It help us to record the chromatogram based on certain characteristics of the analyte and help us in identifying that compound both qualitatively and quantitatively.
HPLC[ HIGH PERPROMANCE LIQUID CHROMATOGRAPHY OR HIGH PRESSURE LIQUID CHROMAT...Dr. Ravi Sankar
GASSCHROMATOGRAPHY[GC], ADVANCED STUDY OF THE FOLLOWING AND THEIR APPLICATIONS, INTRODUCTION, THEORY, COLUMN OPERATION,INSTRUMENTATION AND DETECTION,APPLICATIONS AND ADVANTAGES OF GC,PRINCIPLE OF SEPARATION IN GC, HOW GC MECHINE WORKS? COLUMN, DETECTORS.
BY P.RAVISANKAR, VIGNAN PHARMACY COLLEGE, VADLAMUDI, GUNTUR, A.P, INDIA.
Supercritical fluid extraction and Supercritical fluid chromatography are techniques which use supercritical fluids as solvent for both extraction and separation respectively.
The properties such as density, viscosity and diffusion constant of the supercritical fluids are intermediate between those of a substance in gaseous and liquid state.
This helps in efficient extraction and chromatographic separation compared to other techniques.
Optimum performance laminar chromatography (OPLC) is a pumped flow chromatography techniques that combine the user – friendly interface of HPLC with the capacity of flash chromatography and multidimensionally of TLC .
Optimum performance laminar chromatography (OPLC ) , in a contrast , is a pumped flow chromatography system that uses a planar 2D column format .
The multidimensionally capacity of OPLC is not limited to the separation technique alone , but also to the multitude of sample application and detection methods that are available .
Super Critical Fluid Separation ProcessAbhimanyu Pal
Hello Guys here is a presentation for you named super critical fluid separation process. It may be useful for third year undergraduate of chemical engg. stream. so have a look ,i hope it may be helpful for your project
a brief introduction to countercurrent chromatography with its principle. working and modes of operation along with little bit of history, the types of CCC and its applications
It is my journal club presentation on Synthesis, Docking Studies and Anticancer Activity of New Substituted Pyrimidine and Triazolopyrimidine Glycosides.
I sincerely thank the authors Wael A. El-Sayed, Ashraf M. Mohamed , Hemat S. Khalaf, Dina S. EL-Kady, May Al-Manawaty
It is my Journal club presentation on Docking studies, synthesis, characterization of some novel Oxazine substituted 9-anilinoacridine derivatives and evaluation for their Antioxidant and Anticancer activities as topoisomerase II inhibitors.
I sincerely thank the authors R. Kalirajan*, Vivek Kulshrestha, S. Sankar, S. Jubie, Department of Pharmaceutical Chemistry, JSS College of Pharmacy, (Off Campus, JSS University, Mysore), Udhagamandalam 643001, Tamilnadu, India
This presentation gives us an information regarding the protease enzyme and its development ,development of agents using molecular modelling techniques
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
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
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.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
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
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
3. Chromatography is an separation method used for analysing
mixtures of chemicals using stationary phase and mobile phase.
Chromatography – mobile phase
Gas chromatography - GAS
Liquid chromatography - LIQUID
Supercritical fluid chromatography – SUPERCRITICAL FLUID
4.
5. Supercritical fluid chromatography (SFC) is a form of normal phase chromatography that
uses a supercritical fluid such as CARBON DIOXIDE AS THE MOBILE PHASE.
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.
Triple point is the temperature and pressure at which
solid, liquid & vapour phases of a particular
substance coexist in equilibrium.
The critical point is the point at which two phases of a
substance initially become indistinguishable from one
another.
It is the end point of a phase equilibrium curve, defined by
a critical pressure Tp and critical temperature Pc.
At this point, there is no phase boundary.
6. PRINCIPLE INVOLVED IN SFC
The Principle is based on ADSORPTION AND PARTITION CHROMATOGRAPHY.
7. LIQUIFIED GAS
CARBON DIOXIDE
(COMPRESSED& HEATED)
DECOMPRESSION(BELOW
CRITICALPRESSURE)
SUPERCRITICAL FLUID+
MODIFIER/ CO-SOLVENT
CHROMATOGRAPHIC
COLUMN
TEMPERATURE
NEAR CRITICAL
TEMPERATURE
ELUTION
PRESSURE &
TEMPERATURE
INCREASES
SELECTIVITY
GAS
PHASE
separation with pure CO2 eluent, the
solvent power of the fluid is decreased ,
leading to solute precipitation and eluent-
solute separation.
PRODUCT
+CO2
8. Mostly used are Silica/Alumina
Useful for Non-polar
compounds
WIDELY USED POLAR STATIONARY PHASE ARE
Polysiloxanes - stable, flexible Si--O bond lead to good
diffusion.
Polymethylsiloxanes - increase efficiency in separating
closely related polar analytes
Cyanopropyl polysiloxanes - useful for compounds with –
COOH
Mostly Carbon-dioxide is used.
Disadvantage of carbon dioxide is its inability to elute very polar or ionic compounds.
It is overcomed by adding of Modifier fluid. (Alcohols, cyclic ethers, acetonitrile and chloroform)
Modifier fluid improves the solvating ability and enhances selectivity of the separation.
9. OTHER SFC SOLVENTS
– NITROUS OXIDE - Similar in solvating and separation properties to CO2(expensive)
– ALKANES - Less safe and not as detector compatible than CO2, better solvent
characteristics for nonpolar solutes.
– HALOCARBONS, XENON etc. - Specialty applications only.
– More polar solvents for highly polar &high molecular weight compounds.
10. INSTRUMENTATION
a) PUMPS
b) OVEN
c) INJECTORS
i) LOOP INJECTOR
ii) INLINE INJECTOR
iii) INCOLUMN INJECTOR
d) COLUMN
e) BACK PRESSURE RESTRICTOR
f) DETECTOR
11. a) PUMPS
Flow controlling is an function of pumping systems flow control is necessary and pulseless operation .
Type of pump used in super critical fluid is choosed by column type.
For packed columns - reciprocating pumps are used.
For capillary columns- super critical fluid syringe pumps are used.
Reciprocating pumps allows easier mixing of mobile phase or introduction of modifier fluids.
12. b) OVEN
A Thermostated column oven is required for precise temperature control of the mobile
phase.
Conventional GC or LC ovens are generally used.
13. c) INJECTORS
Injector - For packed SFC A Conventional HPLC Injection System is adequate,
For capillary column sfc, the small volume depends on column diameters.
Small volume must be quickly injected into column.
Therefore Pneumatically Driven Values Are Used.
A) LOOP INJECTORS
B) INLINE INJECTOR
C) INCOLOUMN INJECTOR
14. i) LOOP INJECTORS
– It is a direct transposition of what is applied in analytical SFC
– Used mostly for preliminary tests of column performance and elution
parameters.
15. ii) INLINE INJECTOR
– More Versatile
– System Offers Better Flexibility For Changing Injected Volume.
– High Pressure Pump Required To Inject Feed Solution.
– Injected Stream Dissolves in Diluent Flow
16. iii) INCOLOUMN INJECTOR
An Alternative System
Permits Injection Of Feed Solution Directly Onto Column
No Dilutions Required
17. d) COLUMN
There are two types of analytical columns used in SFC,
– Packed columns contain small deactivated particles so which the stationary phases
adheres the columns are conventionally stainless steel.
– Capillary columns are open tubular columns of narrow internal diameter made off
used silica with the stationary phase bonded to the wall of the column.
18. e) BACK – PRESSURE DEVICE OR RESTRICTOR
It is used to maintain desired pressure in column by pressure adjustable
diaphragm or controlled nozzle, so that, same column outlet pressure is
maintained irrespective of mobile phase pump flow rate.
It keeps mobile phase super critical throughout separation and often must be
heated to prevent clogging
Pressure restriction is placed either at the end of the column or after detector.
19. f) DETECTOR
Most any detector used in GC or HPLC can be used.
a) Flame photometric detectors
b) Flame ionization detectors
c) Refractive index detectors
d) Ultraviolet-visible spectrophotometric detectors
e) Light scattering detectors
20. Mobile phase (liquid) is pumped into the supercritical
region by heating it above its supercritical temperature
before entering into the analytical column.
It passes through an injection valve where the sample is
introduced into the supercritical 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 keeps the mobile phase supercritical
throughout the separation and heated to prevent clogging.
Both variable and fixed restrictors are available.
WORKING
21. It requires HIGH PRESSURE operating conditions (High-pressure vessels are expensive and
bulky) , It is difficult to maintain pressure (backpressure regulation).
Reason :Supercritical fluids are highly compressible and their physical properties change
with pressure - such as the pressure drop across a packed-bed column.
Automated backpressure regulators can maintain a constant pressure in the column even if
flow rate varies.
It is difficult to separate gas/liquid separation during collection of product.
Upon depressurization, the CO2 rapidly turns into gas and aerosolizes any dissolved analytes
in the process.
DRAWBACKS
27. Tofisopam is a member of the 2,3-benzodiazepine compound family used in the treatment
of ANXIETY AND ALCOHOL WITHDRAWAL.
Due to its Stereogenic center at C(5)-atom it exists as TWO ENANTIOMERS (R(+) AND
S(–)).
Upon dissolution, its diazepine ring system will exist in two boat conformations, leading to
two conformers for each enantiomer .
The Driving force for conformer transition is attributed to the steric repulsion effect
between C(4)-methyl and C(5)-ethyl groups.
As a result of the pharmacological interest in Tofisopam, It is essential to separate the four
isomers in order to evaluate their different biological activities of the drug.
28. Agilent 1260 Infinity Analytical SFC System is used.
It consists of A5 fusion module for CO2 pre- and post
conditioning and a modified Agilent 1260 Infinity Binary
LC System for accurate and constant metering of the
mobile phase.
The system (G4309A) consisted of the following modules:
SFC Fusion A5 module
Agilent 1260 Infinity SFC Binary Pump
Agilent 1260 Infinity Standard Degasser
Agilent 1260 Infinity Standard Autosampler
Agilent 1260 Infinity Diode Array Detector with high
pressure SFC flow cell
INSTRUMENTATION
29. Chromatographic conditions
Flow rate - 3.0 mL/min,
Temperature of the column compartments at 35 °C and
Back pressure of CO2 supercritical fluid at 150 bar.
30. MeOH appears to be the most versatile co-solvent in resolution of
Tofisopam isomers
The best resolution of the four peaks was achieved with
CHIRALPAK IA and CHIRALPAK ID.
Analysis times can be as short as 3 minutes (Figure 2 (a)) or 5
minutes (Figure 2 (b)), respectively.
Elution order is the same on CHIRALPAK IA,CHIRALPAK
IC, and CHIRALPAK ID.
Co-elutionof two P(Ax.) and one P(Eq.) is observed on
CHIRALPAK IB
31. SFC was developed in the 1960s, and some commercially available instruments were
introduced to the market in the beginning of the 1980s.
When users found that instruments were difficult to operate, and poorer performance than
HPLC were obtained, the interest in SFC considerably dropped.
There is, nowadays, increasing demand for new, environmentally friendly processes, trends to
banish some classes of solvents (ozone depletion), to prevent or reduce the direct and indirect
effects of emissions of volatile organic compounds (VOCs) in the environment and on human
health.
All these reasons favour the use of SFC.
Considering the numerous advantages of Prep-SFC, especially for rapid chiral separations of
pharmaceutical compounds, its revival in the near future is very likely.
CONCLUSION
32. REFERENCE
Super critical fluid chromatography “Skoog” instrumental analysis Pg: 935 to 940.
Supplement and Cumulative Index, Edited by Bryant W. Rossiter and Roger C. Baetzold
Supercritical Fluids and Nanotechnology Opportunities for Multidisciplinary Collaborative Research
“A Presentation to Air Force Research Laboratory” Edwards, CA by B. Cherhoudi, PhD
Principle and Applications of Supercritical Fluid Chromatography by Wieslaw Majewski a ,
Eric Valery a & Olivier Ludemann‐ Hombourger a NovaSep SAS, Pompey, France