Blue/Green LED Technology

From UV light to Blue/Green LEDs

Why gel documentation is evolving

As molecular biology workflows become more diverse, gel documentation systems must support DNA, RNA, protein and fluorescence applications while preserving SAMPLE INTEGRITY, delivering RELIABLE SIGNAL INTENSITY and enabling SAFE HANDLING.

For many years, UV transilluminators were the standard light source because they efficiently excited common nucleic acid stains. However, UV illumination has important limitations. High-energy UV light can damage DNA by causing strand breaks, mutations and thymine dimer formation. This is especially relevant when gel-excised DNA is used for downstream applications such as cloning, genome editing or sequencing. Even short UV exposure can reduce transformation efficiency and affect experimental success.

UV light also creates handling risks for users, as exposure can affect skin and eyes and requires suitable protection. In addition, regulatory and sustainability trends are increasing pressure on mercury-containing UV lamps. In Europe, several RoHS exemptions for these lamps are currently set to expire on February 24, 2027.

Blue LED transilluminators emerged as a UV-free alternative, improving handling safety and reducing UV-related sample damage. However, conventional blue LED systems usually operate around 470 nm, which can limit excitation range and signal quality, especially for dyes with excitation profiles extending into the green range.

Blue/Green LED technology addresses this limitation by extending visible-light excitation to approximately 470-520 nm. It combines UV-free handling advantages with broader dye compatibility and versatile detection for modern DNA, RNA, protein gel and fluorescent protein applications.

Blue/Green LEDs are completely safe

Protect users, protect samples

While traditional UV transilluminators remain common, they pose risks such as DNA damage and user harm.
UV light is highly energetic and can cause DNA strand breaks, mutations, and thymine dimers, compromising DNA quality and making it unsuitable for cloning, sequencing, and other applications.
Degraded sample integrity can lead to failed experiments or unreliable results.

Blue/Green LED Technology emits light in the safe 470-520 nm range.
This spectrum eliminates the risks associated with UV light exposure of common transilluminators.

Side note: Mercury-containing UV lamps are increasingly subject to regulatory restrictions due to the phasing out of EU RoHS exemptions (more information). Blue/Green LED technology is not affected, making it a future-proof alternative.

Blue/Green LEDs show increadible sensitivity.

More excitation, better signal

Common Blue LED transilluminators, operating only at a single wavelength of 470 nm, also present challenges. Their inefficient excitation of a wide range of DNA dyes results in poor visualization and unsatisfactory imaging quality. This lack of sensitivity with various fluorescent dyes forces researchers to use multiple devices, complicating workflows and increasing costs.

In contrast, high-intensity Blue/Green LED light, with a broad spectral range between 470 nm – 520 nm ensures superior excitation of various dyes, resulting in brighter and clearer images.

Blue/Green LEDs can excite a wide range of fluorescent dyes.

Green, yellow & red DNA/RNA dyes

Blue/Green LED technology offers superior excitation across a broad spectrum of 470–520 nm, making it highly effective for a wide range of fluorescent dyes. Unlike single-wavelength Blue LEDs, this broad range ensures that green (e.g., MIDORI Green), red and yellow nucleic acid dyes absorb energy with maximum efficiency, resulting in high-intensity fluorescence.

Blue/Green LED technology supports the excitation of fluorescent protein dyes and proteins

Beyond nucleic acid detection, the Blue/Green LED technology also supports the excitation of fluorescent protein dyes and commonly used fluorescent proteins such as GFP, YFP, RFP and mCherry. This makes the FAS-X system a versatile solution for fluorescence-based imaging across different molecular biology applications.