Maximize data, minimize stress in LC-MALDI sample preparation

The gap between LC-separation and MALDI-TOF analysis is securely bridged with our spotOn system for target preparation and fraction collection. With guided control from vial to target spot, intuitive workflows, and full visibility into both separation and preparation, potentially complex bottom-up and top- down analyses of biologicals are met with confidence and ease.

LC sample spotting with accuracy and ease

Complex biological samples, including industrially-produced biopharmaceutical products, often require chromatographic separation for in-depth analysis, as they include a very wide and dynamic range of components. Structural features critical to therapeutic function may represent only a small percentage of the total protein content, and even small impurities may necessitate immediate action within a production scheme. The hardware and software components of our spotOn system are designed to support, accelerate, and improve these analytical workflows, saving time and money and enabling a more comprehensive insight into these valuable biologicals.

Fitting conveniently on the benchtop, the spotOn makes target preparation for LC-MALDI workflows faster and easier, promoting optimal MALDI matrix crystallization with all sample fractions for improved data quality and accelerate data collection. Predefined methods and detailed queries for all spotOn necessities, including MALDI targets and matrix solutions, reduce experimental error and promote high reproducibility from run to run, regardless of operator experience.

spotOn interface
nanoElute LC and spotOn status are displayed in one software interface

The Bruker spotOn system is easily connected to a nano- or capillary-LC system and applies LC fractions to our reusable 384 or 1536 spot MALDI targets. Eluent application may be made by fraction time (volume) or the number of fractions desired, and near neighbor calibrants may be included in the target preparation for increased mass accuracy. MALDI matrices can be applied concurrently with the aliquots, or after a controlled drying time, resulting in uniform target spots ready for MALDI analysis. Whether using our nanoElute LC system or instrumentation from other vendors, fractions with analytical LC runs, can simply be collected in well plates for subsequent analyses.

Designed and built for worry-free target preparation

For improved reproducibility and data quality, our spotOn system is built with double independent concentric needles (DICNTM), with an outer needle for piercing seals and septa, and a spotting needle that moves inside the outer needle and dispenses samples. Protected within the outer needle, the spotting needle can be optimized for volume and inertness. The needle pair is thoroughly cleaned inside and out with a combination of air pressure and solvent streams via the spotOn’s PowerWashTMsystem, preventing carryover.



To protect sensitive samples from oxidation during LC separation, an optional mask of inert N2 gas may be applied when using our MTP AnchorChip 384 BC or a MTP BigAnchor 384 BC MALDI target. The integrated bar code reader automatically ensures the correct detection of the N2 mask and the MALDI target type.

Full integration and visibility into LC separation scheme via Hystar software

Bruker’s comprehensive Compass HyStar 5.0 software is used to control the LC components, including the autosampler, pumps, columns, gradients, UV detector. Our plug-in for spotOn leads the operator step-by-step through a sample editor wizard to set up related spotting tasks. During the run, real-time online information allows the user to easily monitor all aspects of sample separation and MALDI target preparation.

user interface spotOn
Wizard driven software in an intuitive graphical user interface allows convenient setup for LC-MALDI analysis

Following target preparation, all sample and LC separation details are transferred to the rapiflex, ultrafleXtreme, or autoflex series MALDI instruments. Data collection can be easily automated, and targeted analysis for biopharmaceutical characterization can be made quickly and confidently via our BioPharma Compass software platform, which simplifies and accelerates protein biopharmaceutical characterization.

Top-down workflows can provide up to 100% sequence confirmation of antibody subunits, revealing sequence aberrations such truncations and amino acid substitutions in a matter of minutes.

LC MALDI based workflows also offer a unique analytical advantage in the creation of a (separated) sample archive. Following evaluation of results from the initial automated data collection, specific target spots can be re-examined for secondary or more intensive MS and MS/MS analyses.

Convenience and confidence to support high-value biopharmaceutical workflows

With our spotOn system bridging the gap between LC-separation and data collection, the combination of chromatographic and time-of-flight separation is even more powerful. Bruker’s efficient and effective solutions for today’s analytic allow for speed, accuracy and detail in MALDI-based characterization of biopharmaceutical products.

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