3. WHAT IS CHROMATOGRAPHY?
• Chromatography is a separation technique used for Qualitative
and
Quantitative Analysis.
• Essential for testing of chemicals in an Industries & academics
• Technique developed in 1941 by Martin & Synge and were
awarded Nobel Prize in 1952 (partition chromatography)
• In 1951 first GC experiment was performed by Martin & James
• Horvath & Lipsky built the first high-pressure liquid
chromatograph. End of the 70’s improvised – High Performance
Liquid Chromatograph instruments become familiar.
• Pharmaceutical industry made HPLC the workhorse beginning
in the 1970s and become boom in 1980s
• Since 2006 advance models like UPLC, RRLC,UFLC, RSLC..
are available
4. CHROMATOGRAPHICSEPARATION
Chromatography is based on a Physical
Equilibrium that results when a solute is
transferred between the mobile and a
stationary phase.
K = Distribution coefficient or Partition ratio
K = CS/ CM
• CS -Molar conc. of the solute in the stationary phase
• CM -Molar conc. of the solute in the mobile phase.
5. SEPARATION IN COLUMN
• In a mixture, each component has a Different
distribution coefficient in liquid Stationary phase
and Mobile phase.
• The sample then has the opportunity to interact
with the stationary phase as it moves past it.
• Samples/ molecules that interact greatly, which
move slowly and weekly interact are move
quickly.
Because of this difference in rates, the sample is Separated
into their components.
“Like Attracts Like – Opposites are Not Attracted”
6. DEFINITIONS
Gradient elution:
Continuously changing the solvent composition during the
chromatographic run is called gradient elution or solvent
programming.
Retention factor (k):1 Also known asthe “capacity factor
(k)”
k = time spent by substance in Stationary
phase time spent by substance in
mobile phase
k = (tR - tM) /tM
Hold-up time (tM): The time required for elution of an unretained
component Retention time (tR) ,
7. DEFINITIONS
Number of theoretical plates (N): A measure of column
efficiency.
For Gaussian peaks, it is calculated by: N = 16(tR/W) 2
where tR is the retention time of the substance, &W is the peak width at
base
Resolution (RS): The resolution is the separation of two components
in a mixture, calculated between peaks (1&2); tR - Retention time & W –
peak width
RS = 2 × (tR2 - tR1)/(W1 + W2)
Symmetry factor (AS): Also known as the “tailing factor”, of a peak is
calculated by: AS = W0.05/2f (Fig-1)
Where W-0.05 is the width of the peak at 5% height from base and f is
the distance from the peak maximum to the leading edge of the peak.
Fig-1
Signal-to-noise (S/N)
ratio: is useful system suitability
parameter. (Sensitivity)
The S/N ratio is S/N ratio = 2H/h )
Signal
Noise
9. NORMAL PHASE HPLC
• Polar stationary phase and non-polar mobile
phase.
• Stationary phase is usually Silica,
Cyanopropyl- bonded, Amino-bonded etc..
Chiral columns
• Mobile phases are Hexane, Heptane, Methylene
chloride, chloroform, diethyl ether , ethyl acetate,
THF or mixture
• Polar samples are retained on the polar
column longer than less polar & non-polar
samples.
• Used for: Water-sensitive compounds / geometric
isomers / cis-trans isomers/chiral compounds.
10. REVERSE PHASE HPLC
• Reverse Phase is opposite to normal phase: Stationary phase
is nonpolar ( C-18 Hydrophobic) and Mobile phase is a polar
liquid; eg. mixtures of water and methanol or acetonitrile.
• Lowering the amount of organic solvent in the mobile phase
increases the retention time.
• Retention is based on Van dar waal’s Interaction between the non-
polar stationary phase and the molecule (Fig)
• Nonpolar samples are retained longer
than polar molecules.
• Over 90% of chromatographers use
RPC
• The technique is used for non-
polar, polar, ionizable and ionic
molecules…
Neproxe
n
11. SEPARATION AND POLARITY
• Chromatographic Retention Behavior
“Like Attracts Like – Opposites are Not Attracted”
• Polars attracted to other Polars
• Non-polars attracted to other non-polars
Polarity Compound Mobile
Phase-
Solvent
Coulmn
Polar Salts
Acids
Alcohol
s
Ketone
s
Ethers
Halogenated
compounds
Aliphatic
hydrocabons
Water Diol
Alcohols Amine
Acetonitrile Silica
Ethylacetate Cyano
THF Phenyl
Dichloromethane C8 (Octyl)
Non-
Polar
Toluene
Hexane
C18
(Octadecyl)
12. ION-PAIR CHROMATOGRAPHY
• Ion-pair chromatography is a subset of reversed-phase
chromatography. Used for separation of complex mixtures of
very polar and ionic molecules.
• Organic salt containing a large organic counter-ion, such as a
quaternary ammonium ion or alkyl sulfonate is added to the
mobile phase as an ion-pairing reagent. Eg. Heptane or Octyl
sulfonic acid (for base) Tetrabutyl ammonium Hydroxide,
certrimide (for acid)
• Ion-pairing reagents having a charge opposite to the analyte of
interest as well as a substantial hydrophobic region that allows
interaction with the stationary phase, plus associated counter-
ions.
• This counter ion forms an uncharged ion pair with a solute ion of
opposite charge in the mobile phase. This ion pair then partitions
into the nonpolar stationary phase giving differential retention of
solutes based on the affinity of the ion pair for the two phases.
13. ION-PAIR CHROMATOGRAPHY
Advantage of Ion-pair chromatography : Reduced separation
times; Highly reproducible results; Sharper peak shapes;
Simultaneous separation of ionized and non-ionized analytes;
and Wide choice of additives to improve separation
Example for Ion-pairing reagent (IPR) and interaction with molecule
Anionic ion-pairing agent:
Adrenaline with an ion-pairing agent
in ODS column.
0.1 M sodium phosphate
buffer/methanol 9:1 containing 0.02 %
sodium octanesulphonic acid (IPR)
Cationic ion-pairing agent :
Ascorbic acid
with anion-pairing agent in ODS
column.
0.1 M sodium acetate buffer pH
4.2, Acetonitrile 95:5 containing
0.03 M cetrimide (IPR)
14. ION-EXCHANGE HPLC
• The stationary phase is Ionically charged
functional groups on polymer
• The mobile phase is an aqueous buffer, where
both pH and ionic strength are used to control
elution time.
• The mobile phase is an aqueous buffer (e.g.
phosphate, formate, etc.).
• Opposite charge of the sample ions are attracted
and elutes later.
• This technique is used almost exclusively with
ionic or ionizable samples.
15. ION-EXCHANGE MECHANISM
• In ion exchange, the column packing contains ionic
groups (Eg. Sulfonic acid , tetraalkyl ammonium )
• Useful for separation of inorganic and organic
anions and cations in aqueous solution.
• Used to test Ionic dyes, amino acids, and proteins etc
Type of
Exchanger
Functional
Exchanger Group
Cation
Strong
acid
Weak
acid
Sulfonic acid-
SO3-, Carboxylic
acid
-COOH,
Anion
Strong
base
Weak
base
Quaternary
ammonium ion -
NR3+
Amine group -NH2
16. SIZE EXCLUSION HPLC
• No interaction between the sample compounds and
the column.
• The column is filled with material having
precisely controlled pore sizes.
• Molecule /particles are separated according to its
their molecular size.
• Molecules larger than the pore opening do not
diffuse into the particles, while molecules smaller
than the pore opening enter the particle and are
separated.
• Large molecules elute first. Smaller molecules elute
later.
• Mainly for polymer characterization and for proteins.
17. SEC RETENTION MECHANISM
Molecular Size in solution
• Analytes are dissolved in solution, injected into mobile
phase
•Analytes are separated by their size once they are in
solution There are two modes:
• Non-aqueous SEC [Gel Permeation Chromatography
(GPC)]
– Used in polymer separations
• Aqueous SEC [Gel Filtration Chromatography (GFC)].
– Used in biomolecule separations.
18. HPLC INSTRUMENTATION
HPLC consists:
1. Reservoir containing the mobile phase,
2. Pump to force the mobile phase through
the system at high pressure,
3. Injector to introduce the sample into the
mobile phase
4. Chromatographic column,
5. Detector
6. Data collection device.
20. HPLC : PUMP
• The role of the pump is to force the mobile phase at a specific
flow rate, (mL/min).
• Normal flow rates in HPLC are in the 1- to 2-mL/min range.
• Typical pumps can reach pressures in the range of 400 to 600
bar.
• During the chromatographic experiment, a pump can deliver a
constant mobile phase composition (isocratic) or an increasing
mobile phase composition (gradient).
• Quaternary pump (low pressure) and binary pump (high
pressure) are available.
• A flow rate range of 1–2 mL/min on a 4.6 mm dia. column
will translate to a flow rate of ∼0.48 - 0.96 μL/ min for a 0.1 mm
dia.
21. HPLC PUMP REQUIREMENT
• The low flow rates obey Poiseuille’s law.
• A flow rate range of 1–2 mL/min on a 4.6 mm dia.
• Columns packed with 3- and 5-μm silica-based particles
required < 400 bar (5800 psi) pressure in HPLC.
• Pressure will increase to maintain same flow rate at
lower particle size. Pressure needed is inverse to the
square of the particle diameter. Eg Pressure required at a
given flow rate is 1100% higher when the column is packed with 1.5
μm particles than with 5 μm particles.
• UHPLC operates with microbore column and pump
pressure designed to1300 bar (19,000 psi) and UPLC
built for > 600bar
• Flow rate of ∼0.48 - 0.96 μL/ min for a 0.1 mm dia.
22. MOBILE PHASE ELUTION
Isocratic (ISO means Same)
• Solvent Composition remains Same
during
the Entire Run.Eg. 60:40 Alcohol: Water
Gradient
• Solvent Composition Changes
throughout the HPLC Run time.
• Gradually Changed or Step Changes
o Analysis time is reduced by proper
composition
& time
o Achieve good Peak Separation/ Resolution
& Peak shapes and Faster analysis of
complex molecules.
23. MOBILE PHASE
• Mobile phase should be thoroughly degassed to
remove all dissolved gasses.
• Dissolved gas can be removed from solution by:
• Bubbling with helium
• Sonication / Vacuum filtration
If the mobile phase is not degassed, air bubbles can
form in the high-pressure system resulting in
problems with system instability, spurious baseline
peaks etc.
• Do not use Online degasser while THF as mobile
phase due to degradation of Teflon in vacuum
chamber.
24. HPLC: INJECTOR
• The injector function is to introduce the sample into Column
along with mobile phase.
• Multiport value
• The injector must also be able to withstand the high pressures
of the liquid system.
• Mostly sample volumes used is 5 to 100 µL.
• Autosampler is available for automatic injection to analyze
many samples continuously by setting the program in the
system
• Fill the vials with sample and keep in the order of injection in
auto sampler tray (100 samples) to inject automatically
– measures the appropriate sample volume,
– injects the sample automatically,
– then flushes the injector to be ready for the next sample and
continue all sample vials until all are processed …
25. HPLC COLUMNS
• Consideredthe “heart of thechromatograph”
• High-purity spherical silica particles with low in trace metal content, of
2-10
μm diameter particles are coated with chemical stationary phase.
• Pore sizes of the particles are 60–150, 200–300, and 1,000–
4,000°A, used for separation of small molecules,
polypeptides/proteins, and very high molecular weight proteins
respectively to allow the analyte to penetrate the pores.
• Nonporous packings- of very small silica particle <1.5 μm
• Most columns for normal & reversed
phase are with length of 5 to 25 cm and
ID of 3 to 5 mm and particle size (PS) 3-
5µm.
• Particle size and pore size are different
for Ion-exchange & Gel-permeation
chromatographic columns.
26. HPLC COLUMNS
• Materials of construction for the Column tubings;
– Stainless steel (gives high pressure capabilities and commonly
used)
– Glass (mostly for biomolecules)
– PEEK polymer (biocompatible and chemically inert to most
solvents)
• Analytical column : Length of 150 – 250 mm & ID 1.0 - 4.6-mm, PS.3
to 5µm (40,000 to 70,000 plates/m)
• Preparative column: Lengths 50 – 250 mm & ID > 4.6 mm
• The below types of columns are advantage of speed and
minimal solvent consumption and high plates > 100,000
plates/m
– Microcolumn: Length 100 – 150 mm & ID 1.0 - 4.6-mm, PS.3 to 5µm
– Capillary: various lengths, ID 0.1 - 1.0 mm;
– Nano (i.d. < 0.1 mm, or sometimes stated as < 100 µm)
27. GUARD COLUMN & GHOST-BUSTER
COLUMN
• 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, system debris from reaching and contaminating
the analytical column.
• In gradient elution unexpected peaks ie Ghost
Peaks may appear.
• Ghost-Buster Column absorb the week polar and non-
polar impurities in the mobile phase and eliminate ghost.
Also baseline drift /fluctuation caused in the gradient is
eliminated and gives stable baseline. It is connected
between mixture and sample injection.
28. COLUMN OVEN
Temperature Control in HPLC: Uniform temperature throughout the run
give reproducible result. Column oven available with 5°C to 85°C.
Reproducibility:
• Retention of molecule is also temperature dependent
• If temperature varies, the peak areas/heights may vary for the specific
compounds. Peaks elutes faster if temperature is high (Ref Fig).
Solubility
• If compounds are low solubility in the mobile phase, in the flow stream they may
precipitate or forms salt in the column, by Increase the temperature or maintain the
column temperature high to overcome
• Stability:
Some of biological compounds such as enzymes
or proteins, may not be stable at room
temperature or higher. The temperature needs to
be much lower down to 4°C
25°C
30°C
35°C
29. DETECTORS
• Detectors sense the separated components and
provide a signal. Selection of detectors based on the
compounds
• All the detectors are either concentration-dependent or
mass
dependant. Can connect multiple detectors for good
response
Commonly used detectors are;
UV-spectroscopy: Dual wavelength & PDA
Refractive Index
Fluorescence,
Mass Spectrometric
Electrochemical detectors
ELSD and etc
30. UV DETECTOR
A modified UV spectrophotometer equipped with a flow cell.
UV light at selected wave length(s) is passes through a flow cell
If a compound elutes from the column that absorbs this light energy,
Absorbed energy is detected by the sensor, which converts as
electrical signal, which is amplified and directed to data system.
Chromatogram is a plot of
absorbance as a function of
elution time (RT)
UV absoption is based on the
chromaphores in the molecule
Energy absorbed is proportional to the
amount of component
The flow cell has a volume of 1–10 µL
and a path length of 0.2–1 cm
Variable Wavelength
Detector
31. DIODE ARRAY DETECTOR
This is working in the same principle of UV detector,
In UV only single or dual wave length is absorbed, but in a
diode array spectrophotometer entire range of spectrum
are recorded
Shows three-dimensional chromatogram
A plot of absorbance against elution time
The flow cell has a volume of 1–10 µL and a path length of 0.2–1
cm.
Diode Array Detector PDAchromatogram
32. REFRACTIVE INDEX (RI) DETECTION
• Snell’slaw of refraction – Sin i/Sin r
• It is a bulk property detector; Any change in its composition is reflected
in the RI.
• The ability of a compound or solvent to deflect light provides a way
to detect.
• The RI is ameasure of molecule’s ability to deflect light in aflowing mobile
phase in a flow cell relative to a static mobile phase contained in a
reference flow cell.
• The amount of deflection is proportional to concentration.
• The RI detector is considered to be a universal detector but it is
not very sensitive.
Limitations:
• Commonly used water methanol
solvent system
• RI changes considerably with temperature
• RI detection is generally incompatible
with gradient elution.
• Not suitable for trace analysis
33. FLUORESCENCE DETECTION
• The fluorescence detector is most sensitive detector than
UV-Vis detectors
• It sense only detect those materials that will fluoresce or, by
appropriate derivatization can be made to fluoresce
• Used in quantify and identify compounds and impurities in
complex matrices at very low concentration levels
• Suitable for trace analysis/ genotoxic impurities
• Output :A plot of fluorescence
intensity as a function of time.
• Less popular than the UV
detectors since molecule
should be fluoresce
34. MASS SPECTROSCOPY (MS)
• An MS detector senses a compound eluting from the HPLC
column first by ionizing it then by measuring it’s mass
and/or fragmenting the molecule into smaller pieces that
are unique to the compound.
• Mass spectrum is like a fingerprint and is quite unique to
that compound.
• The MS detector used to identify the compound with
library in application and also determine the quantity of
molecule.
• MS detector is sensitive and used for trace analysis
35. DATA PROCESSER
• Data system/ processing : The computer controls all the modules of
the HPLC instrument and converts the signal from the detector.
• Algorithms establish the time of elution (retention time) of the
sample components (qualitative analysis) and the peak area ie
amount of sample (quantitative analysis).
• Signals from the detector are processed based on the set of
integration
events and displays the chromatograms for easy to read and interpret.
• Availability of Function for process chromatographic data based on
the application
• Computer with application available with many options like method
development, determine system suitability, calibration, auto
calculation etc. Also used to store, archive & back up of the data
36. PERFORMANCE QUALIFICATION OF
HPLC
Compone
nt
Parameter Acceptance Criteria
Pump Pump Flow Accuracy 0.5ml (0.475 to 0.525) 5.0ml (4.75 to5.25)
Pump flow precision RT % RSD:NMT:0.50
Gradient composition in % 20, 40, 60, 80 + 2.0
Column oven Column TemperatureAccuracy Column Oven: < 2.0
Column Temperature Stability Column Oven: < 1.0
Sample oven Sample temperatureAccuracy Set temperature 4°C: > -2.00 and < 5.00
UV Detector Wavelength Accuracy (201nm to 209nm) 205 nm < 2
(241nm to 249nm) 245 nm < 2
(269nm to 277nm) 273 nm < 2
Noise and Drift Noise: < 0.040 mAU Drift: < 0.500 mAU/Hr
Signal to Noise > 3000
Response Linearity (Resp.Factors) Correlation coefficient: > 0.99900
Lamp Intensity 1000
Sampler /
Injectors
Injector Precision
Volume Delivery - Linearity
% RSD for Area: < 1.0 % RSD for Height: <
2.00
Correlation coefficient: NLT:0.99
Injection Carryover Carryover for Area: < 0.20
Carryover for Area: < 0.40
Ensure the below parameters covered in the Performance
Qualification as minimum, but not limited to;
37. CALIBRATION OF HPLC (UV)
Component Calibration test Acceptance Criteria
Pump Leak Test No leak
Flow rate Accuracy 0.5ml (0.49 to 0.51)
1.0ml (0.98 to 1.02)
2.0ml (1.96 to 2.04)
Flow stability RT % RSD:NMT:1.0
Gradient Delivery Accuracy in % 20, 40, 60, 80 ±2.0%
Column oven
&Sampler
Temperature Accuracy by Calibration
of
Thermocouple and Air temperature
Column Oven:
25°C/40°C/60°C + 2.0
UV Detector Wavelength Accuracy(266nm to
276nm)
271 to 273nm
Dynamic Short-term Noise (Single to
Noise Ratio)
Noise:0.04 mAU or less
Drift:5.0mAU/hr or less
Response Linearity Correlation coefficient: NLT:0.99
Lamp energy Low intensity (> 200)
Average intensity (> 5000)
Highest intensity (> 10000)
Sampler /
Injectors
Volume Precision % RSD :NMT 1.0
Volume Delivery – Linearity Correlation coefficient:NLT:0.99
Injector Carryover NMT 0.1
38. TECHNIQUE & METHOD SELECTION
• Methods can be
chosen based
on solubility and
molecular mass.
• Reversed-phase
is appropriate for
small molecules.
• Ion exchange is suitable
for strong anion & cation
• Size Exclusion
is appropriate
for
high molecular mass
(>M 2000).
41. COLUMN CHEMISTRY
Reverse
phases:
Phenyl : R = -C6H5,
C8 (octyl silane):R = -(CH2)7CH3,
moderate
less hydrophobic
C18/ODS: R = -(CH2)17CH3, hydrophobic
Normal phases :
Cyanopropyl
Diol:
Amino :
Dimethylamino,
[R = (CH2)3CN], less polar
[R = -(CH2)2OCH2CH(OH)CH2OH],
[R = -(CH2)3NH2],
[R = -(CH2)3N(CH3)2] more polar
Silica based columns have limited lifetime at pH levels below 2 or above 8.
42. COLUMN CHEMISTRY
• Silanol in the silica, is bonded with Octyl- or
Octyldecyl group.
• The long-chain hydrocarbon groups are aligned
parallel to one another and perpendicular to the
surface of the particle,
• Present brush like, nonpolar hydrocarbon
surface.
• Silica has limitation of stability
over strong basic or alkaline pH,
• Silanol (Si-OH) encaped to
increase the stability.
• Where required wider pH, Hybrid
columns are used
43. COLUMN AND PH
• Organic–inorganic hybrid silica particle with ethylene
bridge improves the stability to use wider pH range. Eg
Propylene bridged bidentate C18 silane (Fig).
• Chromatographic columns with Graphitic carbon,
alumina, titania, and zirconia are also available for
wider pH
tolerance.
• pH Cross-linked polymeric particles. for
example, poly(methacrylate)s, and
especially cross-linked poly(styrene), can
withstand the full range of pH.
44. CHIRAL COLUMNS
• Silicamatrix bonded to β- and γ - cyclodextrins via a small
hydrocarbon chain /ether linkage.
• These cylindrically shaped ligands, which are oligosaccharides
made of five to seven molecules of glucose, possess a
hydrophobic internal cavity while the external part is hydrophilic.
• Central cavity is somewhat hydrophobic and the outer
surface is hydrophilic.
• This gives them a selective permeability and it forms
reversible diastereoisomer complexes at the surface and
separates.
– Eg.Cyclofructans (CFs) based stationary phases are commonly used in
the normal separation mode of HPLC - to separate chiral primary amine
enantiomers.
45. SELECTION OF HPLC COLUMNS
Bonded
Group
Polarity Retention
mechanisms
Comments
C18, C8,
C4
Nonpolar van der Waals
does
C8 does not retain hydrophobic
compounds as strongly as C18
Phenyl Nonpolar Hydrophobic and
pi-pi
Cyano Intermediate Hydrophobic,
dipole-dipole,
and pi-pi
Resolves polar organic
compounds
by reversed-phase or
normal- phase
chromatography
Amino Polar (NH2)
Ionic ( NH3
Dipole-dipole and
H-bonding
Normal-phase or ion-exchange
separations; separates ionic
carbohydrates, polar organic
compounds, and inorganic
ions; reacts with aldehydes
and ketones
Bare silica Very polar H-bonding Normal-phase
separations
46. FACTORS AFFECTS THE PERFORMANCE
• pH of the mobile phase shuold be close to the pKa value
of compound for better separation.
• Resolution is dependant on three variables, the column
efficiency
(N), capacity factor (k’) & selectivity(α).
• Selectivity is a measure of the relative retention of two adjacent
peaks in a chromatogram
• Capacity factor is affected by changes in mobile phase,
operating temperature, analyte retention characteristics and
changes to the surface chemistry of the column.
• Increasing N increases resolution because peak width decreases.
• Decreasing k’ sharpensthe peaksbut decreasesresolution.
Increasing α increasesresolution.
• capacity factor decreases with an increase in temperature
according to the van’t Hoff equation
47. ADJUSTMENT ALLOWED FOR HPLC
CONDITION
Property USP General Chapter 621 Ph.Eur. Gen.
Chapter 2.2.46
Column length ±70% ±70%
Particle size Reduction by 50% Reduction by 50%
No increase No increase
Internal
diameter
Can be adapted as long as the
linear flow velocity remains
the same
±25%
Flow rate ±50% or more, provided the
linear
flow velocity remains the same
±50%
Columntemp. ±10 °C ±10 °C, maximum 60
°C
pH -mobile
phase
±0.2 units ±0.2 units (±1%
for neutral subs)
48. ADJUSTMENT ALLOWED FOR HPLC
CONDITION
Property USP General Chapter 621 Ph.Eur. Gen. Chapter
2.2.46
Injection
volume
Reduction allowed as far as
precision and detection
limit acceptable. No
increase.
Reduction allowed as far as
precision and detection
limit acceptable. No
increase.
Salt conc. of the
buffer
±10%, as far as the
allowed change in pH
value
±10%
Composition of
mobile phase
Minor components ±30%, if
not more than ±10%
absolute
Minor components ±30%,if
not more than ±2%
absolute (greater value
accepted) *
Wavelength Not permitted , can be Max
±3nm based on the validation
*For gradient separation, a change of the mobile phase is not
recommended
49. ANALYTICAL METHOD VALIDATION
• Ensure that Analytical method used is validated to the
above characteristics and suitable for its intended
purpose (ICH Q2).
• Method should demonstrate Specificity, Precision
(Repeatability Intermediate Precision, Reproducibility ),
Linearity, Range, Accuracy, Robustness, Limit of
Detection & Limit of Quantification as appropriate.
• If test method is as per monograph, ensure that
Analytical method is verified for its suitability Eg USP
General Chapter
<1226>
• Any change in the test method /condition shall be within
the allowable limit of Pharmacopeia methods (next
page)
50. HPLC APPLICATION
• Qualitative Analysis – by comparing the retention time or
volume of the sample to the standard against the
sample.
• Retention time or relative retention time can be used for
identification of eluted compound. Retention times are
characteristic of the compounds they represent (but are
not unique). Mass Detector gives the mass value to
identify precisely.
• Quantitative Analysis- Peak area / Peak height of elution
peak is proportional to the quantity / concentration. Peak
response is based of the detector used.
• Method used for Quantitative Analysis shall be validated
• Type of estimation- Area normalization, Internal
standard, Calibration and standard, Standard addition
and etc
51. HPLC APPLICATION
Pharmaceutical Applications
• Testing of Quality of raw material, in-process , intermediates, APIs and
drug
products
• Pharmaceutical quality control: Assay, related substances, content
and, trace analysis like genotoxic, nitrosamine impurities at ppm
level.
• To perform drug stability.
• Testing the content of pharmaceutical dosages form, content uniformity
• Phytochemical & nutraceuticals- plant extracts, Ginseng, herbal
medicines
Applications in Clinical Tests
• Bio-availability and bio-equivalency
• Toxicology, pharmacology, phatmacokinetics
• Urine analysis, analysis of blood, Bile acids, drug metabolites, urine
extracts, estrogens etc
• Detection of endogenous Neuropeptides in extracellular fluid of brain etc.
52. HPLC APPLICATION
Environmental Applications
• Detection of chemical compounds / contaminant in water and air quality
• Chemical Exposure in the workplace / environment
• Pesticides, herbicides, phenols, polychlorinated biphenyls (PCBs
Applications in Forensics
• Identification & determination of abuse drugs in blood, urine etc. Eg.
Cocaine, steroid, ketamine, amphetamine etc
• Quantification of Drugs, poisons, blood alcohol, narcotics.
• Forensic analysis like textile dyes, chemicals, etc
Industrial Application:
• Identification & determination of cosmetics- Active ingredient content,
purity, impurities and stability study.
• Analysis of Preservative, surfactants, propellants, dyes etc
• Organic chemicals like polymers (e.g. polystyrene, polyethylene)
• Artifcial sweeteners, antioxidants, aflatoxins, additives
• Thermally unstable compounds such as trinitrotoluene (TNT), enzymes
53. TIPS FOR GOOD HPLC PRACTICE
Always use only Ultra pure / Milli-Q water for
HPLC analysis
Ultra pure HPLCwater of 18MΩresistivity
Do not use RO water/de-ionised water for HPLC analysis.
It will have organic and in-organics impurities
If water contains impurities, it will have higher absorption
and lead to poor baseline , drift , ghost peak and less
accurate
• All reagents and solvents should be highest quality.
• HPLC grade reagents & solvents are high purity
will have low UV absorbance
• Low grade solvent contain impurities to produce spurious
peaks, poor peak , high baseline etc
54. TIPS FOR GOOD HPLC PRACTICE
Do not store HPLC columns in buffers. A buffer may precipitate inside
the column, it will clog and affects the packing material.
Mobile phases with 100% or close to 100% buffer may lead to
bacterial growth, which can block the column & frit and packing
material.
Bacteria may also affect the analyte, and organic products from the
dead bacteria may cause "ghost peaks" in chromatograms.
Do not store HPLC columns in solvents that degrade easily tetrahydrofuran
(THF), triethylamine (TEA), trifluoroacetic acid (TFA).
Unstabilized THF can form peroxides which may degrade the column
All buffers should be washed out of the column before flushing
with Acetonitrile.
Gradually start the column washing : Eg Starts the flow with 0.2 ml/min and
increases gradually to 2.0 ml/min and continues for 20min to 30 min or as
per procedure
Have Dedicated Columns for each Method / each product
55. INTEGRATION OF PEAKS
• Do not integrate any peak by manually.
• Integrate all the peaks or else as per procedure
• Always use same processing method for processing of blank,
standard & sample chromatograms in case of Assay & related
substances, etc.
• Verify the processing parameters like
– Threshold,
– Width,
– System suitability,
– Peak names etc.
• Save the processing method
• Re-integration:
– Do not re-integrate the chromatograms without documenting.
– Document the reason for reintegration.
56. COMMON PROBLEMS IN HPLC
ANALYSIS
• System failures may occur during analysis due
to
– System over pressure
– Leakage
– Poor mobile phase
• dissolved gas, pH, solvent purity or composition,
filtration,
– Communication error
– Failure of system suitability
– Peak splitting/ negative peak
– Spurious peak
– Bracketing standard failure
57. HANDLING OF DEVIATION/FAILURE
SOP shall be available and shall address the handling of Lab
deviation/ incidents.
SOP shall define clearly the deviation/ incident , reporting
investigation, CAPA and documentation
Record all the deviation/ incident happened in
chromatographic analysis
Process all the injections including the invalid injection and report
and store the data along with Raw data.
Do not omit any injection
Investigate the deviation/ incident and find the root cause for the
failure.
Rectify the problem, take appropriate CAPA and document
Repeat complete sample set of injections in case of sample
injection failure
58. REFERENCES
1. Chemical Analysis: Modern Instrumentation Methods and
Techniques- Francis and Annick Rouessac and Steve Brooks
- John Wiley & Sons Ltd,.
2. Pharmaceutical Analysis David G. Watson
3. Analytical Chemistry for Technicians -John Kenkel
4. Analytical Chemistry - Gary D. Christian , Purnendu K.
(Sandy) Dasgupta & Kevin A. Schug
5. Quantitative Chemical Analysis- Daniel C. Harris
6. Vogel’s – Quantitative Chemical Analysis- 6th edition
7. Principles of Instrumental Analysis- 6th Edition- D.A. Skoog et
al
8. United States Pharmacopeia
9. European Pharmacopeia
59. 59
ABOUT ME:
I am K.Suresh kumar, born at Tatipally, Medak-Dist, Telangana, India.
Completed my M.Sc.in Analytical Chemistry, NagarjunaUniversity.
Worked asLecturer and also worked in various Chemical & Pharmaceutical
Industries like Cipla, Piramal, Hetero and Bio-Synth for the past 20 years.
Presently working asSr.Manager−Quality at Adeptpharma.Hyderabad.