Why does the site say “<155 nm” instead of an exact lower bound?

GC-UV detection extends well into the vacuum-UV, but the exact lower wavelength a given system reaches depends on the flow cell design, window material, carrier-gas purity, optical path length, and the absorbing species in the sample. Quoting a single fixed number would imply a guaranteed limit across all configurations and matrices, which isn't physically accurate. “<155 nm” communicates the meaningful capability — operation in the vacuum-UV — without overstating performance you can't reproduce in your own setup.

What actually limits the lower wavelength?

Three things dominate: (1) absorption by the carrier gas itself (N₂ is largely transparent down to ~145 nm; O₂ and H₂O cut in much earlier), (2) the transmission cutoff of the flow-cell windows (MgF₂, LiF, and synthetic silica each have different deep-UV cutoffs), and (3) lamp emission and detector quantum efficiency at very short wavelengths. INSCAN is engineered so all three are pushed as far into the vacuum-UV as the application requires.

Does GC-UV always operate at the lowest possible wavelength?

No — and it shouldn't. The optimal wavelength window is chosen per analyte. Many compound classes have their strongest, most selective absorption bands above 155 nm. Going lower buys you sensitivity for non-UV-active compounds and class-level fingerprints, but it isn't free: shorter wavelengths require stricter purge, cleaner gas, and shorter optical paths.

How should I interpret the spec sheets?

Treat the published range (typ. <155–330 nm) as the envelope INSCAN can operate within. The wavelength range that's relevant to your method is a subset chosen during method development, based on your analytes, matrix, and required limits of detection. Our applications team confirms the working window during a feasibility scan.

Is “<155 nm” a marketing hedge?

It's the opposite — it's the honest framing. A specific sub-155 nm number would only be defensible under one configuration with one sample. The “<155 nm” phrasing matches how peer-reviewed GC-UV literature describes vacuum-UV operation, and it's consistent with how spectroscopy vendors quote ranges (e.g. “below 200 nm” for deep-UV HPLC detectors).

What does “far below 155 nm” actually mean in practice?

“Far below 155 nm” means the optical path is engineered to keep transmitting useful signal deep into the vacuum-UV — typically into the 130–150 nm region, and in some configurations approaching the LiF cutoff near 105 nm. In that regime almost every organic molecule has a strong σ→σ* or n→σ* absorption, so even compounds that look “UV-transparent” in conventional HPLC detectors (alkanes, fixed gases, simple halocarbons) become detectable with class-specific spectra.

What limits performance at the deepest wavelengths?

Four things, in order of impact: (1) residual O₂ and H₂O in the carrier and purge gas — both absorb strongly below ~180 nm; (2) window contamination — even a monolayer of pump oil, plasticiser, or fingerprint residue raises the cutoff dramatically; (3) lamp ageing — D₂ and Xe lamps lose deep-UV output before they lose visible output; (4) sample loading — overloaded peaks saturate the detector and broaden into the baseline.

How should customers prepare samples for deep-UV GC-UV work?

Treat it like trace GC-MS, with two extra rules. First, eliminate water and oxygen from the sample path: dry solvents, low-bleed septa, and a fresh split liner before any deep-UV run. Second, control matrix loading — dilute heavy matrices so total mass on-column stays below ~100 ng per analyte. Use UV-grade carrier gas (≥99.9999% N₂ or He) with an in-line O₂/H₂O trap.

INSCANGC-UV Detection Platform

Q: Why does the site say “<155 nm” instead of an exact lower bound?

GC-UV detection extends well into the vacuum-UV, but the exact lower wavelength a given system reaches depends on the flow cell design, window material, carrier-gas purity, optical path length, and the absorbing species in the sample. Quoting a single fixed number would imply a guaranteed limit across all configurations and matrices, which isn't physically accurate. “<155 nm” communicates the meaningful capability — operation in the vacuum-UV — without overstating performance you can't reproduce in your own setup.

Q: What actually limits the lower wavelength?

Three things dominate: (1) absorption by the carrier gas itself (N₂ is largely transparent down to ~145 nm; O₂ and H₂O cut in much earlier), (2) the transmission cutoff of the flow-cell windows (MgF₂, LiF, and synthetic silica each have different deep-UV cutoffs), and (3) lamp emission and detector quantum efficiency at very short wavelengths. INSCAN is engineered so all three are pushed as far into the vacuum-UV as the application requires.

Q: Does GC-UV always operate at the lowest possible wavelength?

No — and it shouldn't. The optimal wavelength window is chosen per analyte. Many compound classes have their strongest, most selective absorption bands above 155 nm. Going lower buys you sensitivity for non-UV-active compounds and class-level fingerprints, but it isn't free: shorter wavelengths require stricter purge, cleaner gas, and shorter optical paths.

Q: How should I interpret the spec sheets?

Treat the published range (typ. <155–330 nm) as the envelope INSCAN can operate within. The wavelength range that's relevant to your method is a subset chosen during method development, based on your analytes, matrix, and required limits of detection. Our applications team confirms the working window during a feasibility scan.

Q: Is “<155 nm” a marketing hedge?

It's the opposite — it's the honest framing. A specific sub-155 nm number would only be defensible under one configuration with one sample. The “<155 nm” phrasing matches how peer-reviewed GC-UV literature describes vacuum-UV operation, and it's consistent with how spectroscopy vendors quote ranges (e.g. “below 200 nm” for deep-UV HPLC detectors).

Q: What does “far below 155 nm” actually mean in practice?

“Far below 155 nm” means the optical path is engineered to keep transmitting useful signal deep into the vacuum-UV — typically into the 130–150 nm region, and in some configurations approaching the LiF cutoff near 105 nm. In that regime almost every organic molecule has a strong σ→σ* or n→σ* absorption, so even compounds that look “UV-transparent” in conventional HPLC detectors (alkanes, fixed gases, simple halocarbons) become detectable with class-specific spectra.

Q: What limits performance at the deepest wavelengths?

Four things, in order of impact: (1) residual O₂ and H₂O in the carrier and purge gas — both absorb strongly below ~180 nm; (2) window contamination — even a monolayer of pump oil, plasticiser, or fingerprint residue raises the cutoff dramatically; (3) lamp ageing — D₂ and Xe lamps lose deep-UV output before they lose visible output; (4) sample loading — overloaded peaks saturate the detector and broaden into the baseline.

Q: How should customers prepare samples for deep-UV GC-UV work?

Treat it like trace GC-MS, with two extra rules. First, eliminate water and oxygen from the sample path: dry solvents, low-bleed septa, and a fresh split liner before any deep-UV run. Second, control matrix loading — dilute heavy matrices so total mass on-column stays below ~100 ng per analyte. Use UV-grade carrier gas (≥99.9999% N₂ or He) with an in-line O₂/H₂O trap.

The patented^* GC-UV detection platform that resolves what GC-MS cannot — for licensing and custom co-development.

*Proprietary GC-UV detection technology protected by pending and granted patents.

Take the Assessment

Leading the way in GC-UV detection.

We make isomers visible.

Labio designs and licenses GC-UV reference platforms used by analytical labs, petrochemical QC, and instrument OEMs. Vapor-phase UV spectra paired with retention time resolve the structural isomers GC-MS cannot — without vacuum pumps, without compromise.

Application Notes

Trace analysis in polymerization processes.

Technical Guides

Method development & validation with GC-UV.

Operating Manuals

INSCAN 176 — system operation & specifications.

Areas of Impact

Where GC-UV makes the difference.

Wherever isomers must be told apart and trace species confirmed, our detectors enable the next answer in analytical chemistry.

Pharma QC

Pharmaceutical QC laboratories live and die by the certainty of their identifications.

Explore Now

Petrochemical

Aromatics define the value and the regulatory profile of refinery streams — yet ortho, meta and para isomers of xylene, ethyltoluene or trimethylbenzene give effectively identical mass spectra.

Explore Now

Environmental

Environmental laboratories work at the limit of what chromatography can offer: ng/L analytes, complex matrices, and a constant pressure to deliver legally defensible identifications.

Explore Now

Forensic Toxicology

Forensic chemistry routinely confronts compounds designed to evade identification.

Explore Now

Polymer & Monomer

Polymer producers and converters rely on tight control of residual monomers, additives, and degradation products.

Explore Now

Fine Chemicals

Fine and specialty chemical manufacturers operate with narrow purity specifications and frequent process changes.

Explore Now

Fuels & Biofuels

Fuels chemistry is regulated end-to-end.

Explore Now

Flavor & Fragrance

In flavor and fragrance, structure is sensory.

Explore Now

Food Safety

Food safety laboratories juggle hundreds of regulated contaminants across thousands of matrices.

Explore Now

Cannabis & Botanicals

The cannabis and botanical extract industries demand precise terpene profiling and cannabinoid quantification under fast-evolving regulatory frameworks.

Explore Now

Analytical Chemistry

GC-UV, Explained.

Gas chromatography with ultraviolet detection (GC-UV) couples the separation power of capillary GC with vapor-phase UV absorbance spectra. Where mass spectrometry sees only mass, UV sees electronic structure — distinguishing positional isomers, double-bond geometry and aromatic substitution patterns that traditional detectors cannot resolve. The result: confirmatory identification, library- matched spectra, and quantitation at trace levels across pharma, petrochemical, environmental and forensic workflows.

UV absorbance spectrum visualization for GC-UV detection

Learn More

Read the full primer on vapor-phase UV detection.

Two GC-UV specialists reviewing analytical results in the lab

Book a Demo

Talk to a GC-UV specialist about your application.

The latest in peer-reviewed GC-UV research

Customer
Publications

313

Total Number of GC-UV Publications

GC-UV Publications This Year

GC-UV Publications Last Month

Indexed mentions of gas chromatography with UV (GC-UV) detection in peer-reviewed literature.

Interactive Comparison

Compare GC-UV against the techniques you already run.

Pick up to four techniques and a domain to see how they perform across qualitative ID, quantitation, isomer separation, co-elution deconvolution, trace sensitivity, and throughput.

Techniques to compare

Select 1–4. GC-UV stays comparable across every domain.

Application domain

Best-match guidance

GC-UV mode: Standard split/splitless GC-UV, full 178–330 nm acquisition
Sample prep: Direct injection or headspace depending on matrix

Pick a domain, sample state, or objective for a tailored recommendation.

Top match96%

GC-UV

Gas Chromatography – UV

Rank 288%

GC-MS

Gas Chromatography – Mass Spec

Rank 369%

HPLC-DAD

HPLC – Diode Array Detector

Pharmaceutical impurities

ID & quantify positional isomers down to 0.05% w/w under ICH Q3.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Full
Isomer Separation	Full	Limited	Partial
Co-elution Deconvolution	Full	Partial	Partial
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Petrochemical & fuels

Discriminates BTEX, PAH and aromatic isomer classes in one run.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Full	Limited	Partial
Co-elution Deconvolution	Full	Partial	Partial
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Environmental (PFAS, VOCs)

Trace-level confirmation at sub-ng on column with UV fingerprint.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Partial	Limited	Limited
Co-elution Deconvolution	Full	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Forensic toxicology

Confirms designer cathinone & cannabinoid isomers court-ready.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Full	Limited	Partial
Co-elution Deconvolution	Partial	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Flavors & fragrances

Spectral unmixing of co-eluting terpenes in essential oils.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Limited
Quantitative	Partial	Full	Partial
Isomer Separation	Full	Limited	Limited
Co-elution Deconvolution	Full	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Polymer & rubber additives

Identifies antioxidants & process aids in pyrolysis extracts.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Partial	Limited	Limited
Co-elution Deconvolution	Partial	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Tobacco & nicotine products

Quantifies nicotine + minor alkaloids at trace levels.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Full	Limited	Limited
Co-elution Deconvolution	Full	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Food safety & residues

Confirms pesticide residues against a UV spectral library.

Capability	GC-UV	GC-MS	HPLC-DAD
Qualitative ID	Full	Full	Partial
Quantitative	Full	Full	Partial
Isomer Separation	Partial	Limited	Limited
Co-elution Deconvolution	Partial	Partial	Limited
Trace Sensitivity	Full	Full	Partial
Throughput	Full	Full	Partial

Pharmaceutical impurities

ID & quantify positional isomers down to 0.05% w/w under ICH Q3.

GC-UVGC-MSHPLC-DAD

Petrochemical & fuels

Discriminates BTEX, PAH and aromatic isomer classes in one run.

GC-UVGC-MSHPLC-DAD

Environmental (PFAS, VOCs)

Trace-level confirmation at sub-ng on column with UV fingerprint.

GC-UVGC-MSHPLC-DAD

Forensic toxicology

Confirms designer cathinone & cannabinoid isomers court-ready.

GC-UVGC-MSHPLC-DAD

Flavors & fragrances

Spectral unmixing of co-eluting terpenes in essential oils.

GC-UVGC-MSHPLC-DAD

Polymer & rubber additives

Identifies antioxidants & process aids in pyrolysis extracts.

GC-UVGC-MSHPLC-DAD

Tobacco & nicotine products

Quantifies nicotine + minor alkaloids at trace levels.

GC-UVGC-MSHPLC-DAD

Food safety & residues

Confirms pesticide residues against a UV spectral library.

GC-UVGC-MSHPLC-DAD

Full Partial Limited Not suitable

Ratings are indicative — actual performance depends on column choice, sample prep, and method development. Talk to us about your specific application.

Bring your hardest peak

Send us a co-eluting pair GC-MS can't separate. We'll show you the GC-UV result.

Free feasibility assessment
Result within 10 business days
Your sample, your method conditions
NDA available on request

Submit a sample challenge

Application Selector

Find Your Match.
See What INSCAN Delivers.

Pick an analytical domain to see the GC-UV benefits, the sample types we routinely handle, and the typical outcomes our customers report.

Tap a domain to view details

Pharmaceutical Impurities

Confirm trace impurities and structural isomers without ambiguity.

GC-UV benefits

●UV spectral confirmation beyond retention time
●Resolves positional isomers MS cannot distinguish
●Trace-level quantitation with calibrated response

Sample types

●APIs & finished drug products
●Genotoxic impurity screens
●Stability & degradation samples

Typical outcomes

●ICH Q3A/B-aligned impurity profiles
●Reduced re-injection rates via first-pass ID
●Audit-ready spectral evidence per peak

Literature Proof

Peer-Reviewed Evidence for GC-UV.

GC-UV only · excludes vacuum-UV (GC-VUV)

A curated selection of published GC-UV studies demonstrating qualitative confirmation, isomer separation, and quantitative performance across real analytical problems. For a side-by-side comparison with vacuum-UV, see our GC-VUV explainer and GC-VUV vs GC-UV comparison.

1985Journal of Chromatography A

Capillary gas chromatographic analysis with the far-UV absorbance detector

What it proves

Far-UV absorbance detection (168–330 nm) coupled to capillary GC delivers structure-selective response unattainable by FID.

Read summary DOI

1999Journal of Chromatography A

Identification of compounds and specific functional groups in the wavelength region 168–330 nm using gas chromatography with UV detection

What it proves

Vapour-phase UV spectra in 168–330 nm provide reproducible functional-group identification that complements MS where mass spectra alone are ambiguous.

Read summary DOI

2002Talanta

Separation and determination of volatile compounds in synthetic wine samples by gas chromatography using UV-visible molecular absorption spectrometry as detector

What it proves

GC with UV-Vis molecular absorption detection quantifies volatile aroma compounds in complex food matrices.

Read summary DOI

2023Chalmers University of Technology — Bachelor Thesis

Identification and Categorisation of Toxic Chemical Gases in Shipping Containers

What it proves

Roughly 30% of intermodal shipping containers carry elevated concentrations of toxic VOCs, and most originate from in-transit off-gassing of cargo — not just fumigation — making on-arrival speciation a safety priority.

Read summary DOI

Reference list available on request. All listings refer to gas chromatography with conventional UV-absorbance detection (GC-UV); vacuum-UV (GC-VUV) results are explicitly excluded. Citation metadata enriched live via the OpenAlex API.

Inside the Lab

Built for the bench, shaped by the work.

INSCAN is designed where it lives — alongside chromatographers, in real laboratories, against real samples. These are the rooms, instruments, and vials that shape every detail of the platform.

Modern analytical chemistry laboratory at golden hour with GC instruments and glassware — The Lab
Where every chromatogram begins.

INSCAN GC-UV instrument on a workbench with autosampler vials and capillary column — In Use
INSCAN at the bench, mid-injection.

Macro view of GC autosampler vials with amber sample fluid in front of an instrument panel — Detail
Sample-ready, vial by vial.

FAQ · UV range

Why we say
“<155 nm,”
not an exact number.

A short, honest explanation of how vacuum-UV performance is bounded — and why a single hard number would mislead more than it informs.

Where far-UV pays off

130–150 nm

Permanent & fixed gases

N₂, O₂, CO, CO₂, CH₄, light alkanes — invisible to FID and HPLC-UV, but each shows a distinct vacuum-UV fingerprint.

140–170 nm

Halogenated solvents & refrigerants

CFCs, HFCs, chlorinated C1–C2 species — strong σ→σ* bands enable class-level ID and isomer separation that GC-MS struggles with.

150–180 nm

Light hydrocarbons & isomers

Linear vs. branched alkanes, cis/trans olefins, cyclic isomers — UV spectra resolve structural differences MS leaves ambiguous.

Compliance notePublished wavelength ranges, detection limits, and spectral performance figures are nominal and vary by analyte, matrix, carrier-gas purity, flow-cell configuration, and lamp condition. They are not guaranteed for any specific application without a Labio configuration review and feasibility scan against representative samples. Contact our applications team before specifying INSCAN for regulated or contractually-bound performance criteria.

Customer Spotlights

See GC-UV in the field.

Company News

Latest from Labio.

Delivering detection that GC-MS cannot.

Labio a.s. is a detection-technology company built around vapor-phase deep UV spectrometry coupled to gas chromatography. Our GC-UV platform unambiguously identifies positional and geometric isomers, classifies compound families, and quantifies via Lambert-Beer — at atmospheric pressure, without vacuum pumps. We commercialize the technology through licensing and partner-led co-development.

Labio is a European technology company developing and licensing GC-UV detection for the analytical instrument industry.

A focused team building deep UV detection from optics to method.

Our team of optical engineers, chromatographers and application chemists has built the GC-UV platform end to end — from the deep-UV light source and atmospheric-pressure absorption cell down to the spectral libraries and quantification workflows. This vertical integration lets us license the technology with full reference designs and support partners through method development, hardware integration and validation.

We work with instrument OEMs, contract laboratories and industrial end-users on two commercial paths: out-licensing of the GC-UV detection technology, and co-development of application-specific GC-UV products. Our reference platform, INSCAN, demonstrates the capabilities of the technology in pharma, petrochemical, environmental, food, fragrance, forensic and clinical breath applications.

Let's show you what our GC-UV instruments are capable of

Book a Demo

Add our technology to your lab and accelerate your discoveries

Get a Quote

Ask our support team if you have any questions about your product

INSCANGC-UV Detection Platform

Leading the way in GC-UV detection.

Trace analysis in polymerization processes.

Method development & validation with GC-UV.

INSCAN 176 — system operation & specifications.

Where GC-UV makes the difference.

GC-UV, Explained.

Read the full primer on vapor-phase UV detection.