Purity & related substances
Area-% purity and the impurity profile of a compound.
Useful forAPIs, intermediates, synthesised compoundsChromatography & Separation
HPLC
High Performance Liquid Chromatography
HPLC separates the components of a liquid sample on a packed column under high pressure and measures each one as it elutes. It is the workhorse for purity, assay and impurity profiling of non-volatile compounds.
1 test optionNon-volatile & polar compoundsPurity, assay and impuritiesTypical turnaround 4–6 working days
HPLC measurement principleIllustrative
01 / Overview
What is HPLC?
In High Performance Liquid Chromatography, a pump drives a liquid mobile phase through a column packed with fine particles. Components of the injected sample interact differently with the packing, leave the column at different times and are recorded by a detector, most often UV or photodiode array.
HPLC handles compounds that are non-volatile, polar or heat-sensitive, which GC cannot. Quantification against reference standards is precise; identity rests on retention time and UV spectrum, so true unknowns may need further techniques such as NMR.
02 / How it works
How it works
- 01
Sample is dissolved
The sample is dissolved in a suitable diluent, filtered and placed in an autosampler vial.
- 02
Pumped at high pressure
A pump pushes the mobile phase and the injected sample through a packed column.
- 03
Column separates compounds
Compounds are held back by the packing to different extents and leave at different times.
- 04
Detector records peaks
A UV or PDA detector measures each compound as it elutes; peak areas give purity or amount.
03 / What it measures
What it measures
Assay & concentration
Quantify an analyte against a calibration made with reference standards.
Useful forFormulations, extracts, reaction mixturesMarker compounds
Quantify marker or active compounds in natural products.
Useful forHerbal extracts, nutraceuticalsReaction monitoring
Follow the conversion of starting material into product.
Useful forSynthesis and process developmentStability samples
Compare assay and impurity growth across time points.
Useful forStability and degradation studies04 / Test options
Choose the HPLC options you need
1 option · none added yet
05 / Sample requirements
Sample requirements
- Accepted forms
- Powders or liquids soluble in water, methanol or acetonitrile
- Quantity
- Typically 50–100 mg solid or 2–5 mL solution per sample
- Method
- Share your method or pharmacopoeial reference if you have one
- Standards
- Reference standards needed for assay and identification
- Mention solubility and a suitable diluent
- Send reference standards for quantification
- Seal and clearly label each sample
- No suspended particles or unfiltered extracts
- No insoluble polymers or inorganic salts as samples
Hazardous or air-sensitive samples: mention it in your request, and attach the MSDS if you have one.
06 / Results & turnaround
Results & turnaround
What you receive
- Chromatogram for each sample
- Peak table: retention time, area, area %
- Purity or concentration against standards
- UV spectra of main peaks (PDA)
- Method conditions and report PDF
Turnaround & pricing
Typically 4–6 working days after samples reach the lab.
Price confirmed in your quotation, depending on user type, options and number of samples.
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