Bio-Rad's EXQuest Spot Cutter: automated cutting of proteins on gels and membranes
Bio-Rad's EXQuest Spot Cutter is a high-precision instrument designed to locate and excise protein spots and bands from electrophoretic gels or membranes. This comprehensive system not only allows for the precise cutting of proteins of interest, but also transfers them directly to microplates for further processing and analysis. Designed to reduce the time spent on manual handling, it offers optimal reproducibility, making it indispensable in proteomics and molecular biology research laboratories.
The device works with different types of gels and stains, whether visible, such as Coomassie blue or silver, or fluorescent, such as SYPRO Ruby and SYPRO Orange dyes. With its robust design and user-friendly interface, the system guarantees reliable results while preserving sample integrity, a crucial step before identification by mass spectrometry.
An integrated system combining imaging and robotics
The EXQuest Spot Cutter combines several technologies in a compact and secure platform. Its imaging system is based on a high-resolution CCD camera equipped with specific filters to detect protein spots with optimal sensitivity. The working area is protected from ambient light to ensure consistent image quality, especially for fluorescent gels.
The device also incorporates a fluidic system for washing the cutting heads and managing waste, thus preventing cross-contamination between samples. A dedicated washing station automatically cleans the cutting tips after each operation, ensuring consistent performance. Precision robotics allows the cutting head to be moved between the gel, the microplate and the washing station with micrometric accuracy.
The gel is held on a spacious tray equipped with clamps and protective sheets that preserve the surface from wear. Depending on requirements, the device can be equipped with a cutting head for gels or membranes, both of which use interchangeable tips of different diameters. These options allow work to be carried out on both large 2D gels and PVDF or nitrocellulose blots.
Optimising the proteomics workflow
In addition to its mechanical precision, the EXQuest Spot Cutter is supported by PDQuest and Quantity One software, which manage images, create cutting lists and track samples. This software allows gel images to be superimposed, areas to be excised to be selected automatically or manually, and coordinates to be exported. The samples are then delivered directly to 96- or 384-well plates, compatible with standard enzyme digestion and mass spectrometry analysis protocols.
This automation significantly reduces human error and improves productivity. Researchers can import cutting lists from various sources, verify the quality of excisions, and, if necessary, rerun an operation on unrecovered spots. The integration of an optional barcode reader further enhances traceability and facilitates the management of large sample volumes.
By combining imaging, robotic cutting and software management, the EXQuest Spot Cutter is a comprehensive solution that speeds up proteomic analyses and ensures reliable sample preparation. It is therefore an essential tool for laboratories seeking to optimise their workflows while ensuring reproducible and actionable results for high-level research.
