Identity
Is the expected substance really present?
Lab tests without jargon
Three simple questions: What is it? How clean is it? Is the sample microbiologically clear?
No single test answers everything. Several suitable methods together create a useful quality picture.
Chemical quality
How much target compound and which side components are measurable?
Microbiology
Are viable microbes or bacterial endotoxins detectable?
Test by test
How testing works — heavily simplified.
01Identity Testing
Verifies whether the substance examined actually corresponds to the expected compound.
Open the plain-language explanation
Identity Testing
Verifies whether the substance examined actually corresponds to the expected compound.
Open the plain-language explanationRoughly how it works
The sample is compared with a known reference or expected measurement pattern.
What the result tells you
Whether measured features match the expected substance.
What it does not tell you
Not automatically purity, quantity, sterility or efficacy.
02HPLC
Separates the components of a sample and reveals purity as well as possible impurities.
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HPLC
Separates the components of a sample and reveals purity as well as possible impurities.
Open the plain-language explanationRoughly how it works
A dissolved sample moves through a separation column. Components appear as peaks at different times.
What the result tells you
How the main component and measurable side peaks relate to one another.
What it does not tell you
A high area percentage alone does not prove identity, actual amount or sterility.
03LC-MS
Combines chromatographic separation with mass spectrometry for precise identity determination.
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LC-MS
Combines chromatographic separation with mass spectrometry for precise identity determination.
Open the plain-language explanationRoughly how it works
Liquid chromatography separates components; a mass spectrometer then measures mass-to-charge signals.
What the result tells you
Whether mass and signal pattern match the expected molecule and which other signals appear.
What it does not tell you
Not every impurity is automatically detected or fully quantified.
04Purity
Describes the proportion of the target substance relative to other measurable components.
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Purity
Describes the proportion of the target substance relative to other measurable components.
Open the plain-language explanationRoughly how it works
Chromatographic signals are evaluated and the target peak is compared with other measurable peaks.
What the result tells you
Relative chemical purity within the selected method.
What it does not tell you
Not absolute fill amount, sterility or clinical safety.
05Content Assay
Determines how much active ingredient a sample actually contains.
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Content Assay
Determines how much active ingredient a sample actually contains.
Open the plain-language explanationRoughly how it works
A calibrated method compares the sample signal with a reference of known concentration.
What the result tells you
How much target substance was measured under the test conditions.
What it does not tell you
Not automatically whether it is sterile, stable or medically suitable.
06Sterility
Examines whether a sample is free of viable, reproducible microorganisms.
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Sterility
Examines whether a sample is free of viable, reproducible microorganisms.
Open the plain-language explanationRoughly how it works
The sample is placed in growth media under controlled conditions and observed for microbial growth over a defined period.
What the result tells you
Whether viable microorganisms were detected under the test conditions.
What it does not tell you
Not general chemical purity or endotoxins; sampling and method remain critical.
07Endotoxin Testing
Tests for bacterial endotoxins, which can be present even without living microorganisms.
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Endotoxin Testing
Tests for bacterial endotoxins, which can be present even without living microorganisms.
Open the plain-language explanationRoughly how it works
A validated reagent assay reacts to bacterial endotoxins and is evaluated against controls.
What the result tells you
Whether endotoxins above the detection or acceptance limit were found.
What it does not tell you
Not a complete search for microbes and not a replacement for sterility testing.
08Appearance Inspection
Documents visible characteristics such as colour, clarity, particles and overall condition.
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Appearance Inspection
Documents visible characteristics such as colour, clarity, particles and overall condition.
Open the plain-language explanationRoughly how it works
Colour, clarity, visible particles, container and condition are inspected and documented under defined conditions.
What the result tells you
Whether visible deviations are present.
What it does not tell you
Invisible chemical or microbiological problems may still exist.
Reading a COA
An analysis certificate is only as good as its evidence.
A logo and percentage are not enough. A verifiable report should connect the sample, method, result and laboratory.
- Unique sample or batch identifier
- Test date and method
- Result with unit and acceptance limit
- Chromatogram or spectrum where relevant
- Identifiable laboratory and report approval
- Matching sample type: raw material is not automatically a finished sterile product
Technical foundations