Download presentation
Presentation is loading. Please wait.
1
High Performance Liquid Chromatography HPLC
dr.hayder obayes hashim University of babylon College of pharmacy
2
Chromatography Mikhail Tsvet in 1900
plant pigments such as chlorophyll, carotenes, and xanthophylls. from Greek chroma which means "color" and graphein "to write.
3
chromatography The term chromatography is employed to describe a wide verity of separation techniques but all of these techniques share the same principle , this principle can be described as the difference in interaction properties of the analyte to two phases . One of these phases is relatively static and called stationary phase and the other is relatively mobile and called mobile phase All the chromatography type that have a liquid mobile phase are called liquid chromatography or LC. Mobile ph. Stationary ph Type of chromatography gas Gas- gas chromatography liqued Gas- liquid chromatography Solid Gas- solid chromatograpy Liquid Liquid – liquid chromatography solid Liquid- solid chromatography Solid – solid chromatography
4
Conventional LC system
called low pressure chromatography in this method the movement of the mobile phase occur solely by gravity or by aid of low pressure pump . The simplest system is composed from: Mobile phase reserver The column A suitable detection method to monitor the content of the post column mobile phase .(usually it is UV/vis detector)
5
General View Of The Method
Assume that we have a mixture of three compound as the following Compound A which has no interaction with the stationary phase Compound B which has a little interaction with stationary phase Compound C has a higher degree of interaction with the stationary phase
6
The action moods of stationary phase
Adsorption Chromatography Normal phase (silica ) Reverse phase (C18, C8 , etc) Ion-exchange chromatography (IEC) Affinity chromatography Size-exclusion chromatography (SEC) Ion paring
7
THE CHROMATOGRAM AND ITS PURPORT
Qualitative and quantitative values the retention factor or k value (may be better than retention time )
8
THE CHROMATOGRAM AND ITS PURPORT
Two components in a mixture cannot be separated unless they have different k values, the means of assessment being provided by the separation factor, α, formerly known as the relative retention
9
THE CHROMATOGRAM AND ITS PURPORT
Resolution is a term used to describe the degree of separation between neighboring solute bands or peaks. N, the number of theoretical plates, is one index used to determine the performance and effectiveness of columns, and is calculated using equation
10
Chromatographic efficiency
Both of these parameters ( the long retention time and narrow peak width ) can be enhanced by increasing the surface area of the stationary phase
11
The born of HPLC The best way to increase the surface area of the stationary phase is by using a stationary phase composed of small particles . But the usage of small particles stationary phase develop a very high resistance to the movement of the mobile phase Hagen–Poiseuille equation To overcome this resistance a high pressure pump is used to force the mobile phase through this small particles stationary phase column . This kind of chromatography is called high pressure liquid chromatography or high performance liquid chromatography and abbreviated to HPLC .
12
Isocratic and gradient mobile phase
Isocratic mobile phase: mean that the composition of the mobile phase ( type , concentration ) is unchanged in all over the chromatographic procedure . Gradient mobile phase : mean that the mobile phase composition ( type , concentration ) is changed during the chromatographic procedure . time min mobile A mobile B 30 70 2 5 80 20 15
13
HPLC System
14
HPLC systems Can be classified according to column diameters
1- Micro HPLC ( column diameters <2mm) 2- Analytical HPLC ( column diameters 3-5 mm) 3- Semi-Preparative HPLC ( column diameters 6-30 mm) 4- Preparative ( column diameters >30mm)
15
Analytical and Preparative HPLC systems
16
HPLC Detectors UV-VIS Detector : the most commonly used detector.
Its response is specific to a particular compound or class of compounds depending on the presence of light absorbing functional groups of eluting molecules. It is cheap and versatile but unspecific .
17
HPLC Detectors Fluorescence Detector
Greater sensitivity than a UV-VIS detector. However, the number of naturally fluorescent compounds is smaller in comparison to light absorbing compounds. This limitation is overcome by post or pre column derivatization.
18
HPLC Detectors Mass Spectroscopic Detector
Very high sensitivity and selectivity. Detection is based on fragmentation of molecules by electric fields and separation on basis of mass to charge ratios of fragmented molecules. LC –MS technique has opened up new application areas due to advantages of resolution and sensitivity. Expensive and sophisticated
19
HPLC Detectors Diode Array Detector
used to record the ultraviolet and visible (UV-vis) absorption spectra of samples. This enables qualitative information to be gathered about the samples. the ability to select the best wavelength for analysis. Spectra matching
20
Peak purity by diode array detector
If a peak is pure all UV-visible spectra acquired during the peak’s elution or migration should be identical.
21
The Capability of HPLC We can detect the presence of certain compound or compounds in the sample . We can not detect unknown compound in the sample by conventional HPLC (UV, DAD , etc) The unknown compounds can be detected by LC-MS or preparative HPLC then diagnosed by other techniques . We can separate the compounds in the sample We can check the sample purity .
22
HPLC method We can develop and validate our method . this can be tedious and costly . The best choice is to use previously validated method . We have to choose the method according to our need ,material and devices availability .
23
What are the information that we have to know from the previously validated method to do our detection and separation by HPLC ? Sample treatment before the injection some samples need only filtration while the other sample need a specific extraction or derivatization or other treatment . The chromatography conditions : 1- The amount of the sample that have to be injected . 2- The mobile phase type , concentration ,gradient or isocratic , flow rate ,( we have to keep the linear flow rate ) Volumetric flow rate = Linear flow rate * Column cross area The column parameters 1- type of stationary phase 2- The size of the stationary phase particles And its pores size . 3- column length 4- the internal diameter of the column (ID) 5- the column temperature Detector parameters 1- wave length 2- sampling rate 3- constant time 4- time scheduled program Linearity , LOD ,LOQ
24
Qualitative HPLC analysis
25
Qualitative HPLC analysis
26
Quantitative Analysis
External Standard Calibration
27
Internal standard calibration
X axis values :Concentration of Ex st/concentration of (IS) Y axis values : The peak area of Ex st / peak area of IS
28
Internal standard calibration
The Good internal standards compound have to be : Elute near to, but are well resolved from, the analyte of interest chemically and physically similar to the analyte Not present in the original sample mixture Unreactive towards any of the sample components Available in highly pure form Added in the concentration range of the expected MAXIMUM analyte concentration .
29
THANK
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.