LC-MS/MS Analysis

What Is LC-MS/MS Analysis?

LC-MS/MS is a system in which a triple quadrupole mass spectrometer is coupled after liquid chromatography. The first analyser selects the precursor ion, the collision cell fragments it, and the third analyser monitors the product ions. The monitored precursor-product pair is called a transition (MRM).

Purpose of LC-MS/MS Analysis

The purpose is to reliably measure very low concentrations in samples with intense matrix interference. Trace analysis of blood, plasma, food and environmental samples is done with this technique.

Which Products Is LC-MS/MS Analysis Applied To?

Drug and metabolite levels in biological samples
Mycotoxin and veterinary drug residues in food
Nitrosamine impurities in pharmaceutical products
Polar pollutants in water
Adulteration screening in supplement products

In Which Sectors Is LC-MS/MS Analysis Used?

ChemistryPharmaceuticalsFoodCosmeticsEnvironmentBiotechnologyAgriculturePublic Sector

Standards Related to LC-MS/MS Analysis

ICH M10 (bioanalytical method validation)
EU 2021/808 (performance criteria for residue methods)
EN 15662 (QuEChERS)
ICH M7 / EMA nitrosamine guidelines

LC-MS/MS Analysis Conditions

Monitoring: At least two MRM passes for each analyte
Teyit: Compatibility of inter-transition ion ratio with the reference
internal standard: If possible, isotope labeled analog is used
Calibration: Matrix matched calibration if matrix effect is present

Equipment for LC-MS/MS Analysis

UPLC/HPLC system
Triple quadrupole mass spectrometer
Electrospray ion source
SPE and automated sample preparation units
Nitrogen generator and vacuum system

Sample Requirements for LC-MS/MS Analysis

Protein precipitation, liquid-liquid extraction or SPE is required for biological samples
Homogenisation and QuEChERS-type extraction are applied for food
The sample must be sent in the cold chain and in suitable tubes
The list of sought analytes must be defined at the outset

Duration of LC-MS/MS Analysis

Run time is mostly under 15 minutes; sample preparation and method validation determine the main duration.

LC-MS/MS Analysis Procedure

1The sample is homogenised and internal standard added.
2Extraction and clean-up are applied.
3The extract is injected onto the LC column.
4MRM transitions are monitored for the target analytes.
5Ion ratios are compared against the reference.
6Quantity is calculated via the calibration curve.
7Recovery, blank and quality-control results are assessed.

LC-MS/MS Analysis Acceptance Criteria

The result's acceptability is assessed against the limits in the relevant residue, contaminant or impurity regulation. The method does not define a limit.

Evaluation of Results

The result is meaningful within the method's validated working range. Values below the range are reported as 'below the limit of quantification' rather than being forced into a numerical value.

LC-MS/MS Analysis Report

Sample description, receipt date and laboratory number
Method applied and reference standard, if any
Instrument and measurement conditions
Sample preparation steps
Measurement results and units
Measurement uncertainty (if requested)
A statement that the results relate only to the sample submitted for testing

Accreditation

EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.

Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.

Scope and authorisations

Related Regulations

EU 2023/915 (contaminants in food)
EU 37/2010 (veterinary drug residues)
EMA/CHMP nitrosamine evaluations

Pages Where This Method Is Used

Analytical Methods — What Does This Group of Methods Do?

The section below describes the field that the LC-MS/MS Analysis test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.

Analytical method pages are pages about a MEASUREMENT TECHNIQUE rather than about a test. The difference matters: "salt spray testing" is a test and answers one question; "ICP-MS" is a technique and is used in dozens of different tests. Sometimes the user is looking not for the test but for the technique — because the method name is what appears in their specification.

This distinction becomes decisive in choosing a laboratory. When a customer asks for "heavy metal analysis", the real question is by which technique it will be done: XRF is fast and non-destructive but does not distinguish compounds; AAS is economical for a single element; ICP-OES screens multiple elements; ICP-MS sees trace levels. The same sample gives results with different detection limits and different uncertainties across the four techniques.

Method selection is made against three criteria. DETECTION LIMIT: is the concentration sought within the range the method can see? MATRIX COMPATIBILITY: is the sample matrix (plastic, food, soil, metal) one the method can handle, and is pre-treatment required? SPECIFICATION LINK: does the product standard or legislation mandate a particular method? The third often overrides the first two — the specification binds the method.

Method pages build a CHAIN. A technique is linked to the test pages where it is used, to the standards those tests rest on, to the legislation those standards are tied to and ultimately to market access regimes. The example chain in the source document works like this: XRF → metal analysis → RoHS compliance → heavy metal restriction → coating pages. Whichever link the user enters from, they reach the others.

Sample preparation is the invisible half of the result in this family and is a greater source of error than the technique itself. The digestion method, degree of grinding, extraction solvent and dilution ratio change the result markedly. The same sample on the same instrument gives a different result with different preparation; the definition of the method therefore covers preparation too.

Calibration and verification are the third determining component. An instrument is calibrated with certified reference material, the calibration curve is verified periodically and a control sample is run in each batch. Without these steps, a number produced is not traceable even if the instrument is working correctly.

Method groups in this field

Elemental analysis
ICP-OES, ICP-MS, AAS and XRF. They differ in detection limit, matrix tolerance and multi-element capacity.
Chromatography
GC, GC-MS, HPLC, LC-MS/MS and ion chromatography. It separates a mixture into its components and measures each separately.
Spectroscopy
FTIR, Raman, UV-Vis and optical emission. For material identity, functional group identification and alloy composition.
Thermal analysis
DSC, TGA, DMA and dilatometry. Transition temperatures, composition, decomposition and dimensional behaviour.
Microscopy and imaging
Optical microscopy, SEM-EDS, radiography and tomography. Structure, defects and elemental distribution.
Classical (wet) chemistry
Titration, gravimetry and colorimetry. Used as a reference method and in confirming instrumental results.

Commonly confused in this field

XRF is a screening tool; it sees elements and does not distinguish compounds. A decision on a restricted compound requires confirmation by wet chemistry.
The phrase "not detected" is not proof of absence; it is read together with the detection limit of the method.
The specification binds the method. A technically better method is not accepted if the specification calls for another.
Sample preparation is part of the result; a report that does not state the preparation is not reproducible.
Results obtained by different techniques cannot be compared directly; their detection limits and uncertainties differ.
A method page is not a test page; which method applies to which test comes from the product standard.

Which decisions these results support

Matching the method written in the specification to the laboratory's scope
Method selection according to detection limit and matrix compatibility
Confirming an instrumental result with a reference method
Eliminating deviations arising from sample preparation

Related Tests

Frequently Asked Questions About LC-MS/MS Analysis

Why is an isotope-labelled internal standard important?

Because it shows the same chemical behaviour as the analyte, it tracks the matrix effect and extraction loss one-to-one. This significantly improves the accuracy of the result.

What does a result below the limit of quantification mean?

It does not mean the analyte is absent, but that it is below the level the method can reliably measure. The report states this with a separate statement.