Acquisition of a in situ DLS equipment, SpectroLight 610

The Department of Chemistry at the Faculty of science is heavily engaged in research in all aspects of Chemistry including Protein Chemistry. Study of structure and function of proteins is central for researchers in the Biological Chemistry and Chemical Biology sections, in particular.

The instrument is being purchased primarily from a grant from the Carlsberg foundation for expansion of the protein characterization facilities in the Biological Chemistry Section at the Department of Chemistry, University of Copenhagen, with an in situ dynamics light scattering (DLS) instrument (as well as another instrument already purchased). The primary users of the instrument will be protein crystallographers, wishing to monitor sample quality including in crystallization drops, in special screening trays and very small volumes. Other projects involve monitoring proteins and other macromolecules’ aggregation.

SpectroLight 610 is designed to apply in situ dynamic light scattering (in situ DLS) to standard 96 well format (SBS-format) plates, combining with UV and bright light microscopic imaging. Due to the unique combination of methods it is an ideal instrument for the given purpose of protein sample quality check/buffer/ligand optimization for biophysical and structural studies and monitoring crystallization of proteins, for example detecting nucleation or detecting aggregation.

The instrument provides:

A fully automated non-invasive in-drop DLS and imaging system designed to operate on standard plates to perform high throughput DLS-measurements in sub-microliter volumes (min. vol. ~50-100 nl - max. vol. no limit). Due to the very low volume used screening experiments can be performed even with samples which can be produced only in very small amounts.

Particle radius assignment in a range of 1 nm to ~5 µm.

An automatic DLS-laser positioning algorithm. The positioning system can be also used to investigate inhomogeneous samples, e.g. partly aggregated, for further optimization or to avoid dust particles, which couldn’t be measured with competitors’ systems.

Single or serial measurements on a variety of conditions in parallel to yield a maximum of information for biomolecule characterization.

Monitoring of the ongoing crystallization process in SBS-format standard plates, specialized crystallization plates such as MRC crystallisation plates, or smaller plates, like Terasaki or Douglas Instruments batch crystallisation plates with an adapter which is included.

Bright light imaging with 2 µm resolution enabled by a built in microscope.

SpectroLight 610 combines in situ dynamic light scattering, white light imaging and intrinsic fluorescence imaging by connection of the external UV-light source XtalLight 100. Intrinsic fluorescence imaging is used to distinguish salt from protein crystals and as such a very important requirement for the desired application.

No cleaning steps are involved in applying the instrument and the software is optimized for users with a background in structural biology.