Biocomplex is specialized in macromolecular sample preparation and purification for functional and structural studies using preparative ultracentrifugation, monolithic chromatography and asymmetrical flow field-flow fractionation technologies. Biocomplex also actively develops new purification methods for large biopolymers, often in co-operation with manufacturers. Our technologies can be used in different combinations to purify large macromolecular complexes such as viruses, virus-like particles, viral subassemblies, exosomes, membrane vesicles, large protein complexes, and ribonucleoprotein complexes as an important first step in the structure analysis pipeline. Samples produced at Biocomplex can be further studied at the CryoEM facility located in the same building (see Electron Microscopy, Helsinki). We accept both visits and shipped samples. Please contact grp-biocomplexservice@helsinki.fi for enquiries.
Asymmetrical flow field-flow fractionation (AF4) provides size-based separation of sample components. It is applicable for separation of macromolecules, nano- and microparticles and vesicles from 1 nm up to 1 µm. Separation is done in liquid phase without stationary phase. The benefits of AF4 are the following: (i) gentle size-based separation in liquid phase; (ii) large dynamic size range; (iii) rapid analysis time; (iv) high yields; (v) possibility to perform purification under conditions which best maintain the integrity and native structures of the biomolecules. Users are supported in their experimental design, equipment operation and data interpretation. Biocomplex has a new AF4 device (Eclipse NEON) equipped with five high quality inline detectors. The premium setup has multiangle (DAWN) and dynamic light scattering (QELS) detectors as well as UV, refractive index (Optilab dRI) and fluorescence detectors. This setup can be used for characterization and purification of samples: the device has automatic and manual sample feeding and a fraction collector. The accompanied software enables simulation of experiments and analysis of the molar mass, size, conformation, conjugation and other physical parameters from experimental data. Later this year, the service will be supplemented with Mobility EAF4 (Electrical/asymmetrical flow-field flow fractionation) that couples size-based separation to charge-based separation and can be used to determine zeta potential distributions.
Monoliths have a continuous single-piece stationary phase forming interconnected channel networks with widths of 1-5 μm. Service includes weak (DEAE) and strong (QA) anion exchange CIM columns, but please ask for other column types. The benefits of CIM columns are the following: (i) large pore sizes enable entering and binding of large macromolecular complexes to the matrix; (ii) high flow rates promote fast separation; (iii) high yields and sample concentrations can be achieved. More information on Biocomplex services.
Preparative ultracentrifugation is commonly used for purification of large biocomplexes. The separation can be achieved based on the size, shape, mass, and density of the complexes. The preparative ultracentrifugation service provides technologies for density gradient (rate-zonal, equilibrium, and flotation) and differential centrifugation. Several ultracentrifuges, swing-out and fixed-angle rotors with different volume capacities are available for large-scale preparative approaches. We also have instrumentation for gradient making and fractionation of the ultracentrifugation tubes. Superspeed centrifuges are available also for the users. More information on Biocomplex services.
If you aim to work with genetically modified organisms or your work requires Biosafety Level 2 (BSL2) facility, please contact us in advance (grp-biocomplexservice@helsinki.fi). Both genetically modified organisms and Biosafety Level 2 samples (Finnish criteria) can be handled but may require acquisition of permits.
Instruments available: Biocomplex instruments.
Viikinkaari 9
00790, Helsinki
Finland
