At SEDERE, we pride ourselves on being the industry leader in the manufacture of Low-Temperature Evaporative Light-Scattering Detectors (LT-ELSD) for HPLC, U-HPLC, HTLC, µ-HPLC, GPC, Preparative HPLC, Flash Chromatography, Counter Current Chromatography and SFC. Throughout the years, our focus has always been on catering to our customers’ versatile needs. Our product range consists of 6 different LT-ELSDs – from entry-level unit to fully automated analysis systems, powered by a plethora of drivers. Our proprietary technology provides us with 100% turnover and thanks to our established distribution network, over 95% of our products are distributed across the world. Our passion for innovation and for transforming the chromatography industry has helped us build solid, long-lasting relationships with research specialists from academia and some of the brightest minds in the world.
SEDERE is the industry leader in the development, manufacture and distribution of SEDEX detectors, recognised as a best-in-class product in Low-Temperature Evaporative Light-Scattering Detection (LT-ELSD).
Quality, Reliable and Versatile
Leveraging industry expertise, innovation and dedication to hard work, SEDERE offers a full range of pioneered LT-ELSD products for chromatography laboratories. Our emphasis is on quality, reliability and versatility and our product range reflects our utmost dedication to innovation and performance.
Unparalleled Selection of Products
At SEDERE, we aspire to go beyond what’s possible. We work around the clock to continually raise the bar for high sensitivity, high flexibility and high-fidelity detector performance for chromatography. To meet and exceed our customers’ needs, we present an unparalleled selection of six LT-ELSD models, developed in accordance with best-in-class practices and suited for a range of budgets and chromatography needs.
At SEDERE, we aspire to do things differently. Our passion for innovation is the driving force behind our work; as a small company, we leverage unparalleled attention to detail with infinite curiosity and commitment to quality to serve our customers and continually challenge what is possible.
SEDERE’s emphasis is on LT-ELSD products, developed exclusively for the needs of chromatography laboratories around the globe. Our roots can be traced back to 1989, where we laid the foundations of SEDERE.
Since then, we have over 30 years of experience and innovation under our belts and we are working around the clock to deliver high-performance, high-fidelity LT-ELSD products for the chromatography industry.
With over 30 years of experience, SEDEX brings innovation, fidelity and unparalleled performance for a range of chromatography applications.
The Evaporative Light-Scattering Detectors, manufactured by SEDERE are designed exclusively to provide a universal detection mode for Liquid Chromatography and Supercritical Fluid Chromatography.
What gives our products a cutting-edge is that their performance doesn’t depend on the presence of chromophore groups in the compound, which makes the ELSD technology an incredibly versatile and useful technique to obtain a complete picture of complex samples.
Some of the applications of the Evaporative Light-Scattering Detectors include:
- Carbohydrates, Lipids, Surfactants, Polymers
- Also Pharmaceutical High Throughput Screening
- Small molecules such as Amino Acids (without any derivation step)
- Inorganic Ions (without the need for any additional post-column devices).
- SEDERE Head Office is in Alfortville, close to Paris, FRANCE.
- Research, Development, Manufacturing, Support and Applications capabilities are located in Orléans, FRANCE.
The Low-Temperature Evaporative Light-Scattering Detector (LT-ELSD)
Basically all compounds which are less volatile than the mobile phase can be detected. Detection is based on a Universal property of all analytes and does not require the presence of any chromophoric group, electroactive group, etc.
The detector response is directly related to the mass of the eluted compound. Therefore it provides similar response factors for molecules with close structures and this is quite convenient to simplify quantification procedures or to make them possible when standards are not commercially available.
Gradient mobile phases can be used to analyze samples. Since the mobile phase is removed from the eluent before detection, a gradient can be performed to optimize the separation. With ELS detection, a broad range of mobile phase modifiers such as AcONH4, AcOH, HCOONH4, HCOOH, CO3NH4, TFA, HFBA, or N(C2H5)3 can be readily used to separate complex samples.
Step 1: Nebulization
Nebulize Eluent and select Small Droplets
Nebulization: The Eluent from the column is mixed with an inert gas and goes through the narrow orifice of a nebulizer to generate a homogeneous mist. This fine mist is composed of droplets of mobile phase containing the compound of interest.
SEDEX LT technology allows the selection of droplets as a function of their size in order to prevent larger droplets from entering the evaporation (drift) tube. Large droplets would require higher temperatures to be dried and are responsible for increased background noise.
Step 2: Evaporation
Evaporate at Low Temperature
Evaporation of the Mobile Phase: The nebulized eluent goes through a heated drift tube to evaporate the mobile phase.
Solute molecules are obtained from the mist using a heated evaporation (drift) tube, at a low temperature. All SEDEX detectors are designed to evaporate mobile phases with high boiling points at very low temperatures. This unique feature minimizes the potential for evaporation or thermal decomposition of the compounds of interest, and makes the SEDEX LT technology a more reliable way to detect everything in the sample.
Step 3: Detection
Detect Scattered Light
Detection: The stream of solid particles enters a flow cell which includes a light source and a photomultiplier or a photodiode. The intensity of the light scattered by the particles is directly related to the mass of the eluted compound.
The solute molecules from the mist, assisted by Gas Supported Focusing (GSF), go through an optical head designed to measure the scattered light. GSF involves the addition of gas to focus the solute particles within the optical head for enhanced detection and safety.
All SEDERE detectors feature Low Temperature operation to ensure that the superb sensitivity is provided even for semi-volatile or thermally labile compounds. These detectors can be used with conventional analytical and preparative Liquid Chromatography, as well as with U-HPLC, HTLC, µ-HPLC, GPC, Flash Chromatography, CCC and SFC.
Why Low-Temperature evaporation is important in ELS detection?
In an ELS detector, the nebulized eluent is evaporated by going through a heated tube. The temperature of this tube is undoubtedly the most critical parameter when optimizing detection. If the temperature is too high, semi-volatile or thermally labile compounds in the sample may evaporate or decompose and will not be detected.
SEDEX detectors can evaporate solvents with high boiling points at low temperatures. As an example, the SEDEX 90LT can completely evaporate a mobile phase composed of 100% H2O with a flow rate of 1mL/min at 32°C.
Also, our innovative design provides performance that is superior to that obtained from systems which require a special low temperature device!
The unique design of SEDEX LT-ELSD Nebulization cell allows the selection of the droplets as a function of the size. Large droplets, which are more difficult to evaporate, are responsible for an increased noise level. In the glass nebulization cell, the largest droplets are simply discarded, so that the temperature can be lowered, without compromising the sensitivity (signal to noise ratio):
This diagram illustrates the selection of the droplets as a function of the size. The mist of droplets is created by the nebulizer, and is composed of droplets of various sizes. The nebulization cell acts as a real Size Exclusion Selector, so that the droplets of largest dimension (in blue on Figure) are evacuated to the waste. Only droplets which are below a size limit are allowed to flow through the drift tube.
Most of our competitors’ ELSDs do not select droplets and require higher temperatures to reach acceptable levels of noise during the analysis, resulting in much lower sensitivities for semi-volatile and thermo-labile compounds.
Selection of the droplets is a unique feature of SEDEX LT-ELSD and provides the real Low-Temperature evaporation, and the best sensitivity for all compounds.