This document provides an overview of the instrumentation of high performance liquid chromatography (HPLC). It discusses the main components of HPLC including mobile phase reservoirs, pumping systems, sample injection systems, columns, detectors, and data collection devices. The pumping systems are usually reciprocating pumps that can generate high pressures. Columns separate components via stationary and mobile phases. Common detectors discussed are based on properties like UV absorption.
Identification of Seepage Path by Tracer methodPrashant Ojha
Leakage is a major safety issue that, if left unchecked, may result in dam failure by various mechanisms. There is enormous pressure on dam operators to repair leaks without significant delays. Frequently, the need to reduce the risk of failure or control water loss has led to costly remedial repairs that are planned and executed without a complete understanding of the problem. A lack of appropriate leakage investigation and monitoring can result in repairs that are unsuccessful in controlling or reducing leakage.
In the last few decades, a series of new hydrological techniques have been developed to help in the assessment of leakage and seepage in dams. It is important to make these techniques available to the engineers responsible for dam construction and management so that they become aware of these tools. The available literature on dam leak studies is relatively limited with regard to the use of these techniques when assessing dam leakage. It is difficult to find case studies that discuss integrating the use of several of these techniques in comprehensive evaluations that lead to successful leakage mitigation. These techniques allow identification of recharge zones, preferential paths, and transit times, which aid in monitoring and mitigating the dam leakage.
The paper includes description of the techniques and projects in India involving prevention and detection of dam and reservoir leakage, including leakage evaluation, analysis, design, construction, and post-construction verification of repairs.
Identification of Seepage Path by Tracer methodPrashant Ojha
Leakage is a major safety issue that, if left unchecked, may result in dam failure by various mechanisms. There is enormous pressure on dam operators to repair leaks without significant delays. Frequently, the need to reduce the risk of failure or control water loss has led to costly remedial repairs that are planned and executed without a complete understanding of the problem. A lack of appropriate leakage investigation and monitoring can result in repairs that are unsuccessful in controlling or reducing leakage.
In the last few decades, a series of new hydrological techniques have been developed to help in the assessment of leakage and seepage in dams. It is important to make these techniques available to the engineers responsible for dam construction and management so that they become aware of these tools. The available literature on dam leak studies is relatively limited with regard to the use of these techniques when assessing dam leakage. It is difficult to find case studies that discuss integrating the use of several of these techniques in comprehensive evaluations that lead to successful leakage mitigation. These techniques allow identification of recharge zones, preferential paths, and transit times, which aid in monitoring and mitigating the dam leakage.
The paper includes description of the techniques and projects in India involving prevention and detection of dam and reservoir leakage, including leakage evaluation, analysis, design, construction, and post-construction verification of repairs.
Spatial analysis of groundwater quality using GIS systemPavan Grandhi
To analyze systematically for physio-chemical parameters such as pH, Total Hardness, Electrical Conductivity and Chemical Oxygen Demand (COD).
Generate Ground Water Quality Map based in Jnanabharathi ward no.129, Bangalore, Karnataka state, India
This presentation deals with the recent advancement in the field of ground water sampling and analysis technique and water born survey as well as Indian scenario to interpret.
Analysis of groundwater quality of visnagar taluka, mehasana district gujaratvishvam Pancholi
Ground water is the principal source of drinking water in our country and indispensable source of our life. The quality of water is of vital concern for mankind, since it is directly linked to human welfare. The present work investigated various physiochemical parameters of villages of Visnagar taluka of Mehsana district, Gujarat. Because of north Gujarat is affected by various water quality parameters like fluoride is high in many parts of north Gujarat. A total of 50 water samples will be collected from the tube wells for post-monsoon season and analyzed for the various physiochemical parameters like pH, electrical conductivity (EC), nitrate (NO3-), magnesium (Mg2+), Calcium (Ca2+), hardness, and alkalinity, sulphates (SO42-), chloride (Cl-), sodium (Na+), potassium (K+), Fluoride (F-) and total dissolved solids (TDS). The result were compared with standards prescribed by IS: 10500(2012). It was found that the ground water contaminated at 16 sampling sites namely Khadalpur, Chhogala, Sunshi, Denap, Jetalvasana, Tarabh, Visnagar Rural, Bhalak, Kamalpur (GOT), Kamalpur (KHA), Kansa, Magaroda, Pudgam, Sadutala, Thalota, Vadu while other 34 sampling sites showed physiochemical parameters within the water quality standards and quality of water is good so it is fit for drinking uses.
Classification either on quality or type based for groundwater can offer great advantages especially in regional groundwater management. It provides a short, quick processing, interpretation for a lot of complete hydro-chemical data sets and concise presentation of the results. There is a demonstrable need for a quality assurance, with the advanced usage of world's largest fresh water storage i.e Ground water. Its getting depleted over the years and the quality of the same degrading with a rapid pace. Ground water Quality is assessed mainly by the chemical analysis of samples. The data obtained from the chemical analysis is key for the further classification, analysis, correlation etc. Graphical and Numerical interpretation of the data is the main source for Hydro-chemical studies. In this paper we test the performance of the many available graphical and statistical methodologies used to classify water samples including: Collins bar diagram, Stiff pattern diagram, Schoeller plot, Piper diagram, Durov's Double Triangular Diagram, Gibbs's Diagram, Stuyfzand Classification. This paper explains various models which classify, correlate etc., summarizing the water quality data. The basic graphs and diagrams in each category are explained by sample diagrams. In addition to the diagrams an overall characterization of hydro-chemical facies of the water can be carried out by using plots which represents a water type and hardness domain. The combination of graphical and statistical techniques provides a consistent and objective means to classify large numbers of samples while retaining the ease of classic graphical presentation.
ELECTRO DIALYSIS FOR THE DESALINATION OF BACKWATERS IN KERALAcivej
With the declining freshwater source and increase in demand for the potable water need of desalination
have increased. The electrodialysis can be put as an economic substitute for the desalination of the
brackish water. This paper deals with the assessment of the effect contaminants in the desalination of
natural brackish water using electrodialysis. The contaminants studied were Boron, Sulfate and
Magnesium in the presence of chloride. The study was based on the function of pH at a constant voltage
of 11 V. Magnesium, Chloride, and Sulfate was not affected by the pH variations and was removed to an
efficiency of 94%, 95%, and 74% respectively. But the boron was not removed in neutral pH and showed
a removal efficiency of 41% at pH 10 in an hour. There was significant interference in the removal of the
Chloride ion and Sulfate ion.
Chromatography is a laboratory technique for the separation of a mixture. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase.
Spatial analysis of groundwater quality using GIS systemPavan Grandhi
To analyze systematically for physio-chemical parameters such as pH, Total Hardness, Electrical Conductivity and Chemical Oxygen Demand (COD).
Generate Ground Water Quality Map based in Jnanabharathi ward no.129, Bangalore, Karnataka state, India
This presentation deals with the recent advancement in the field of ground water sampling and analysis technique and water born survey as well as Indian scenario to interpret.
Analysis of groundwater quality of visnagar taluka, mehasana district gujaratvishvam Pancholi
Ground water is the principal source of drinking water in our country and indispensable source of our life. The quality of water is of vital concern for mankind, since it is directly linked to human welfare. The present work investigated various physiochemical parameters of villages of Visnagar taluka of Mehsana district, Gujarat. Because of north Gujarat is affected by various water quality parameters like fluoride is high in many parts of north Gujarat. A total of 50 water samples will be collected from the tube wells for post-monsoon season and analyzed for the various physiochemical parameters like pH, electrical conductivity (EC), nitrate (NO3-), magnesium (Mg2+), Calcium (Ca2+), hardness, and alkalinity, sulphates (SO42-), chloride (Cl-), sodium (Na+), potassium (K+), Fluoride (F-) and total dissolved solids (TDS). The result were compared with standards prescribed by IS: 10500(2012). It was found that the ground water contaminated at 16 sampling sites namely Khadalpur, Chhogala, Sunshi, Denap, Jetalvasana, Tarabh, Visnagar Rural, Bhalak, Kamalpur (GOT), Kamalpur (KHA), Kansa, Magaroda, Pudgam, Sadutala, Thalota, Vadu while other 34 sampling sites showed physiochemical parameters within the water quality standards and quality of water is good so it is fit for drinking uses.
Classification either on quality or type based for groundwater can offer great advantages especially in regional groundwater management. It provides a short, quick processing, interpretation for a lot of complete hydro-chemical data sets and concise presentation of the results. There is a demonstrable need for a quality assurance, with the advanced usage of world's largest fresh water storage i.e Ground water. Its getting depleted over the years and the quality of the same degrading with a rapid pace. Ground water Quality is assessed mainly by the chemical analysis of samples. The data obtained from the chemical analysis is key for the further classification, analysis, correlation etc. Graphical and Numerical interpretation of the data is the main source for Hydro-chemical studies. In this paper we test the performance of the many available graphical and statistical methodologies used to classify water samples including: Collins bar diagram, Stiff pattern diagram, Schoeller plot, Piper diagram, Durov's Double Triangular Diagram, Gibbs's Diagram, Stuyfzand Classification. This paper explains various models which classify, correlate etc., summarizing the water quality data. The basic graphs and diagrams in each category are explained by sample diagrams. In addition to the diagrams an overall characterization of hydro-chemical facies of the water can be carried out by using plots which represents a water type and hardness domain. The combination of graphical and statistical techniques provides a consistent and objective means to classify large numbers of samples while retaining the ease of classic graphical presentation.
ELECTRO DIALYSIS FOR THE DESALINATION OF BACKWATERS IN KERALAcivej
With the declining freshwater source and increase in demand for the potable water need of desalination
have increased. The electrodialysis can be put as an economic substitute for the desalination of the
brackish water. This paper deals with the assessment of the effect contaminants in the desalination of
natural brackish water using electrodialysis. The contaminants studied were Boron, Sulfate and
Magnesium in the presence of chloride. The study was based on the function of pH at a constant voltage
of 11 V. Magnesium, Chloride, and Sulfate was not affected by the pH variations and was removed to an
efficiency of 94%, 95%, and 74% respectively. But the boron was not removed in neutral pH and showed
a removal efficiency of 41% at pH 10 in an hour. There was significant interference in the removal of the
Chloride ion and Sulfate ion.
Chromatography is a laboratory technique for the separation of a mixture. The mixture is dissolved in a fluid called the mobile phase, which carries it through a structure holding another material called the stationary phase.
Use of automation to achieve high performance solid phase extractionGERSTEL
Despite 40 years of SPE using LC sorbents, LC principles have been ignored due to the lack of flow control in SPE devices. Variable flow results in variation in results. Internal standards are used to achieve meaningful results. Measuring absolute recovery against external standards to demonstrate absence of matrix effect (gold standard) isn’t done. With a new SPE device, this is changed. It uses a syringe to achieve both automation & accurate flow. With GERSTEL, SPE & LC/MS/MS is automated in a single parallel workflow. van Deemter curves are measured & SPE performed at flow achieving >99% absolute recovery. As a micro device, sample dry down isn’t needed for enrichment up to 200x. SPE is performed efficiently, economically, & with performance matching all LC knowledge of the last 50 years. Examples of laboratory testing using reverse phase & ion exchange SPE are provided.
Gas chromatography is widely used techniques for separation of gaseous and volatile substances which are difficult to separate and analyze It is simple and inexpensive method , generally efficient in regard to separation.
Briefly introduce what flash chromatography is and its purpose in scientific research.
Explain the key principles of flash chromatography, including the differences between normal phase and reverse phase chromatography.
Discuss the equipment required for flash chromatography and the different types of media that can be used.
Provide examples of when flash chromatography is commonly used in scientific research, such as in drug discovery or natural product isolation.
Discuss the advantages and limitations of flash chromatography compared to other chromatography techniques.
Highlight any novel or innovative applications of flash chromatography that you may have explored in your research.
Conclude with a summary of the key takeaways from your presentation, including any practical tips or advice for those looking to use flash chromatography in their own work.
Gas chromatography is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance or separating the different components of a mixture.
Low amount of sample
Complex mixture.
Gas chromatography is a process of separating component(s) from the given crude drug or mixture by using stationary phase (solid or liquid) and gaseous mobile phase. It involves a sample being vaporized and injected onto the head of the chromatographic
column. The sample is transported through the column by the flow of inert, gaseous
mobile phase. The column itself contains a solid or liquid stationary phase which is adsorbed onto the
surface of an inert solid.
Gas Chromatography in Analytical Analysis.pptxRAHUL PAL
Gas chromatography is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture.
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Empowering the Data Analytics Ecosystem: A Laser Focus on Value
The data analytics ecosystem thrives when every component functions at its peak, unlocking the true potential of data. Here's a laser focus on key areas for an empowered ecosystem:
1. Democratize Access, Not Data:
Granular Access Controls: Provide users with self-service tools tailored to their specific needs, preventing data overload and misuse.
Data Catalogs: Implement robust data catalogs for easy discovery and understanding of available data sources.
2. Foster Collaboration with Clear Roles:
Data Mesh Architecture: Break down data silos by creating a distributed data ownership model with clear ownership and responsibilities.
Collaborative Workspaces: Utilize interactive platforms where data scientists, analysts, and domain experts can work seamlessly together.
3. Leverage Advanced Analytics Strategically:
AI-powered Automation: Automate repetitive tasks like data cleaning and feature engineering, freeing up data talent for higher-level analysis.
Right-Tool Selection: Strategically choose the most effective advanced analytics techniques (e.g., AI, ML) based on specific business problems.
4. Prioritize Data Quality with Automation:
Automated Data Validation: Implement automated data quality checks to identify and rectify errors at the source, minimizing downstream issues.
Data Lineage Tracking: Track the flow of data throughout the ecosystem, ensuring transparency and facilitating root cause analysis for errors.
5. Cultivate a Data-Driven Mindset:
Metrics-Driven Performance Management: Align KPIs and performance metrics with data-driven insights to ensure actionable decision making.
Data Storytelling Workshops: Equip stakeholders with the skills to translate complex data findings into compelling narratives that drive action.
Benefits of a Precise Ecosystem:
Sharpened Focus: Precise access and clear roles ensure everyone works with the most relevant data, maximizing efficiency.
Actionable Insights: Strategic analytics and automated quality checks lead to more reliable and actionable data insights.
Continuous Improvement: Data-driven performance management fosters a culture of learning and continuous improvement.
Sustainable Growth: Empowered by data, organizations can make informed decisions to drive sustainable growth and innovation.
By focusing on these precise actions, organizations can create an empowered data analytics ecosystem that delivers real value by driving data-driven decisions and maximizing the return on their data investment.
Opendatabay - Open Data Marketplace.pptxOpendatabay
Opendatabay.com unlocks the power of data for everyone. Open Data Marketplace fosters a collaborative hub for data enthusiasts to explore, share, and contribute to a vast collection of datasets.
First ever open hub for data enthusiasts to collaborate and innovate. A platform to explore, share, and contribute to a vast collection of datasets. Through robust quality control and innovative technologies like blockchain verification, opendatabay ensures the authenticity and reliability of datasets, empowering users to make data-driven decisions with confidence. Leverage cutting-edge AI technologies to enhance the data exploration, analysis, and discovery experience.
From intelligent search and recommendations to automated data productisation and quotation, Opendatabay AI-driven features streamline the data workflow. Finding the data you need shouldn't be a complex. Opendatabay simplifies the data acquisition process with an intuitive interface and robust search tools. Effortlessly explore, discover, and access the data you need, allowing you to focus on extracting valuable insights. Opendatabay breaks new ground with a dedicated, AI-generated, synthetic datasets.
Leverage these privacy-preserving datasets for training and testing AI models without compromising sensitive information. Opendatabay prioritizes transparency by providing detailed metadata, provenance information, and usage guidelines for each dataset, ensuring users have a comprehensive understanding of the data they're working with. By leveraging a powerful combination of distributed ledger technology and rigorous third-party audits Opendatabay ensures the authenticity and reliability of every dataset. Security is at the core of Opendatabay. Marketplace implements stringent security measures, including encryption, access controls, and regular vulnerability assessments, to safeguard your data and protect your privacy.
Techniques to optimize the pagerank algorithm usually fall in two categories. One is to try reducing the work per iteration, and the other is to try reducing the number of iterations. These goals are often at odds with one another. Skipping computation on vertices which have already converged has the potential to save iteration time. Skipping in-identical vertices, with the same in-links, helps reduce duplicate computations and thus could help reduce iteration time. Road networks often have chains which can be short-circuited before pagerank computation to improve performance. Final ranks of chain nodes can be easily calculated. This could reduce both the iteration time, and the number of iterations. If a graph has no dangling nodes, pagerank of each strongly connected component can be computed in topological order. This could help reduce the iteration time, no. of iterations, and also enable multi-iteration concurrency in pagerank computation. The combination of all of the above methods is the STICD algorithm. [sticd] For dynamic graphs, unchanged components whose ranks are unaffected can be skipped altogether.
Explore our comprehensive data analysis project presentation on predicting product ad campaign performance. Learn how data-driven insights can optimize your marketing strategies and enhance campaign effectiveness. Perfect for professionals and students looking to understand the power of data analysis in advertising. for more details visit: https://bostoninstituteofanalytics.org/data-science-and-artificial-intelligence/
As Europe's leading economic powerhouse and the fourth-largest hashtag#economy globally, Germany stands at the forefront of innovation and industrial might. Renowned for its precision engineering and high-tech sectors, Germany's economic structure is heavily supported by a robust service industry, accounting for approximately 68% of its GDP. This economic clout and strategic geopolitical stance position Germany as a focal point in the global cyber threat landscape.
In the face of escalating global tensions, particularly those emanating from geopolitical disputes with nations like hashtag#Russia and hashtag#China, hashtag#Germany has witnessed a significant uptick in targeted cyber operations. Our analysis indicates a marked increase in hashtag#cyberattack sophistication aimed at critical infrastructure and key industrial sectors. These attacks range from ransomware campaigns to hashtag#AdvancedPersistentThreats (hashtag#APTs), threatening national security and business integrity.
🔑 Key findings include:
🔍 Increased frequency and complexity of cyber threats.
🔍 Escalation of state-sponsored and criminally motivated cyber operations.
🔍 Active dark web exchanges of malicious tools and tactics.
Our comprehensive report delves into these challenges, using a blend of open-source and proprietary data collection techniques. By monitoring activity on critical networks and analyzing attack patterns, our team provides a detailed overview of the threats facing German entities.
This report aims to equip stakeholders across public and private sectors with the knowledge to enhance their defensive strategies, reduce exposure to cyber risks, and reinforce Germany's resilience against cyber threats.
Levelwise PageRank with Loop-Based Dead End Handling Strategy : SHORT REPORT ...Subhajit Sahu
Abstract — Levelwise PageRank is an alternative method of PageRank computation which decomposes the input graph into a directed acyclic block-graph of strongly connected components, and processes them in topological order, one level at a time. This enables calculation for ranks in a distributed fashion without per-iteration communication, unlike the standard method where all vertices are processed in each iteration. It however comes with a precondition of the absence of dead ends in the input graph. Here, the native non-distributed performance of Levelwise PageRank was compared against Monolithic PageRank on a CPU as well as a GPU. To ensure a fair comparison, Monolithic PageRank was also performed on a graph where vertices were split by components. Results indicate that Levelwise PageRank is about as fast as Monolithic PageRank on the CPU, but quite a bit slower on the GPU. Slowdown on the GPU is likely caused by a large submission of small workloads, and expected to be non-issue when the computation is performed on massive graphs.
4. INTRODUCTION
CHROMATOGRAPHY
physical method in which separation of components takes place between two
phases-a stationary phase and a mobile phase•
STATIONARY PHASE
The substance on which adsorption of the analyte (the substance to be separated
during chromatography) takes place. It can be a solid, a gel, or a solid liquid
combination
MOBILE PHASE : solvent which carries the analyte (a liquid or a gas)
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-
Cengage Learning (2013) 4
5. HISTORY
• The late 1960s, was the technology developed for producing and using
packings with particle diameters as small as 3 to 10 mm.
• This technology required instruments capable of much higher pumping
pressures than the simple devices that preceded them. Simultaneously,
detectors were developed for continuous monitoring of column effluents.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 5
6. HPLC
• HPLC stands for “High-performance liquid chromatography”
• sometimes referred to as High-pressure liquid chromatography
• HPLC is a chromatographic technique that can separate a mixture of
compounds
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 6
7. BLOCK DIAGRAM
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 7
8. INSTRUMENTATION OF HPLC
Mobile-Phase Reservoirs and Solvent Treatment Systems
Pumping Systems
Sample Injection systems
Columns for HPLC
HPLC Detectors
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 8
9. Mobile-Phase Reservoirs and Solvent
Treatment Systems
• HPLC instrument is equipped with one or more glass reservoirs, each of
which contains 500 mL or more of a solvent.
• Provisions are often included to remove dissolved gases and dust from the
liquids.
• Dissolved gases can lead to irreproducible flow rates and band spreading
• In addition, both bubbles and dust interfere with the performance of most
detectors.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 9
10. • An isocratic elution in HPLC is one in which the solvent composition
remains constant.
• A gradient elution in HPLC is one in which the composition of the
solvent is changed continuously or in a series of step
• gradient elution frequently improves separation efficiency, just as
temperature programming helps in gas chromatography
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 10
11. PUMPING SYSTEMS
• PROPERTIES
The requirements for liquid chromatographic pumps include
(1) the generation of pressures of up to 6000 psi (lb./in2 ),
(2) pulse-free output,
(3) flow rates ranging from 0.1 to 10 mL/min,
(4) flow reproducibility of 0.5% relative or better, and
(5) resistance to corrosion by a variety of solvents.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 11
12. TYPES OF PUMPING SYSTEM
RECIPROCATING PUMP
• Reciprocating types are used in almost
all commercial instruments.
• commercial instruments are equipped
with computer-controlled devices for
measuring the flow rate by
determining the pressure drop across a
restrictor located at the pump outlet.
SCREW DRIVEN SYRINGE
• Syringe-type pumps produce a
pulse-free delivery whose flow rate
is easily controlled.
• They suffer, however, from
relatively low capacity (,250 mL)
and are inconvenient when solvents
must be changed
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 12
13. Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 13
14. SAMPLE INJECTION SYSTEMS
• The most widely used method of sample introduction in liquid
chromatography is based on a sampling loop.
• an integral part of liquid chromatography equipment and have
interchangeable loops capable of providing a choice of sample sizes ranging
from 1 to 100 mL or more.
• The reproducibility of injections with a typical sampling loop is a few tenths
of a percent relative.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 14
15. COLUMNS FOR HPLC
• Liquid chromatographic columns are usually constructed from stainless steel
tubing, although glass and polymer tubing, such as polyetheretherketone
(PEEK), are sometimes used. In addition, stainless steel columns lined with
glass or PEEK are also available.
• TYPES OF COLUMNS
1. Analytical Columns
2. Precolumns
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013)
15
16. ANALYTICAL COLUMNS
• Most columns range in length from 5 to 25 cm and have inside diameters of
3 to 5 mm. Straight columns are invariably used.
• The most common particle size of packings is 3 or 5 mm. Commonly used
columns are 10 or 15 cm long, 4.6 mm in inside diameter, and packed with 5-
mm particles. Columns of this type provide 40,000 to 70,000 plates/m.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 16
17. PRECOLUMNS
• Two types of pre columns are used.
SCAVENGER COLUMN
A pre column between the mobile phase reservoir and the injector is used for
mobile-phase conditioning and is termed a scavenger column. The solvent
partially dissolves the silica packing and ensures that the mobile phase is
saturated with silicic acid prior to entering the analytical column. This
saturation minimizes losses of the stationary phase from the analytical column.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 17
18. GUARD COLUMN
positioned between the injector and the analytical column. A guard column is a
short column packed with a similar stationary phase as the analytical column.
The purpose of the guard column is to prevent impurities, such as highly
retained compounds and particulate matter, from reaching and contaminating
the analytical column. The guard column is replaced regularly and serves to
increase the lifetime of the analytical column
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 18
19. COLUMN PACKINGS
• Two types of packings are used in HPLC, pellicular and porous particle.
• The original pellicular particles were spherical, nonporous, glass or
polymer beads with typical diameters of 30 to 40 mm.
• The typical porous particle packing for liquid chromatography consists of
porous micro particles having diameters ranging from 3 to 10 mm; for a
given size particle, a very narrow particle size distribution is desirable.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 19
20. DETECTOR
• HPLC detector must have low internal volume (dead volume) to minimize
extra-column band broadening. The detector should be small and compatible
with liquid flow.
• Unfortunately, no highly sensitive, universal detector system is available for
high-performance liquid chromatography. Thus, the detector used will
depend on the nature of the sample
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 20
21. DATA COLLECTION DEVICES
• Signals from the detector might be gathered on graph recorders or electronic
integrators that fluctuate in many-sided quality and in their capacity to
process, store and reprocess chromatographic information.
• The PC coordinates the reaction of the indicator to every part and places it
into a chromatograph that is anything but difficult to interpret.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 21
22. CONCLUSION
• The HPLC is mostly used analytical technique. It is having several
advantages. With the use of HPLC one can produce extremely pure
compounds. It can be used in both laboratory and clinical science. With the
use of HPLC the accuracy, precision and specificity can be increased. The
only disadvantage of HPLC is high cost.
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage Learning (2013) 22
23. REFERENCES
• Rogatsky E. Modern high performance liquid chromatography and HPLC
2016 International Symposium. J Chromatogr Sep Tec.
• Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch -
Fundamentals of Analytical Chemistry-Cengage Learning (2013)
Douglas A. Skoog, Donald M. West, F. James Holler, Stanley R. Crouch - Fundamentals of Analytical Chemistry-Cengage
Learning (2013)
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