Bioimaging

The facility is equipped with instrumentation for both light and electron microscopy.

Facility staff provide full training and technical support to suit your needs. From total beginners to those who are more experienced. Training is normally provided 1-to-1 at the instruments. Small groups with similar requirements can be accommodated on request. 

We specialise in the imaging of plants and fungi but can also cater for a wide-range of imaging requirements for insect and animal cells. We offer advice on choice of techniques, experimental design, image interpretation and image analysis. The bioimaging facilities can be used in two ways:

• Use-it-yourself – once you are fully trained you can use the imaging facilities with ongoing technical support.
• Full service – our highly-skilled staff can provide for your imaging needs, with the emphasis on collaborative projects.

We provide:

• Routine sample preparation service, such as embedding and sectioning.
• Many specialised techniques and bespoke services.
• Various types of fixed cell imaging.
• Dedicated data analysis workstations – you can analyse your data in-house.

If a specialist technique or our extensive input is required we encourage collaboration, often resulting in a joint publication.

The bioimaging facility primarily supports the microscopy needs of Kew Science but is available to external customers, both academic and industrial.
 

Sample preparation

SEM sample preparation

Quorum Q150TS Sputter coater

A Quorum dual coater high resolution sputter-coater for use with our field emission SEM. Targets routinely available are Au or Pt. Can be configured for carbon evaporation for EDX analysis. 

• Touch and swipe capacitive screen.
• Multiple-user profiles can be set up on one machine.
• New software sorts recipes per user according to recent use.
• Capable of achieving vacuum of 5 x 10-5 mbar

Leica EM CPD300 Critical Point Dryer

The Leica EM CPD300 critical point dryer dries biological specimens such as pollen, tissue, plants, insects, as well as industrial samples, like Micro Electro Mechanical Systems (MEMS) or Micro fluids and gels in a fully automated and controlled process. You can rely on the same high sample quality from every run. The procedure of critical point drying is an efficient method for drying delicate samples for SEM applications. It preserves the surface structure of a specimen which could otherwise be damaged due to surface tension when changing from the liquid to gaseous state.

Sectioning facilities

Reichert and RMC ultramicrotomes, conventional and cryo, for ultra-thin and semi-thin resin sectioning for both light and electron microscopy applications. We have a knife-maker (Leica KMR3) for preparing glass knives, a Leica EM Trim pyramitome for shaping resin blocks, hot-plates for drying slides, and light microscopes for checking sections, alongside a slide-staining area.

Leica Autocut RM 2155 semi-automatic rotary microtome (for wax or resin) and a Reichert-Jung rotary microtome for wax sectioning.

Sliding, sledge and cryo-microtomes. Automatic knife sharpeners for tungsten steel knives.

High pressure freezer and freeze substitution unit

A Leica EM Ice high-pressure freezer, with 3mm and 6mm carriers, used for freezing very small samples at pressures of ~2000 bar, to prevent ice-crystal growth. Sample size is extremely limited, but it can provide the best method for membrane-preservation. Due to the challenging nature of this technology, it requires technical assistance.

The Leica AFS2 for freeze substitution machine is generally used after high-pressure freezing but can also be used for the PLT embedding method (progressively lowering temperature). Both these methods have been shown to help retain antigenicity and are therefore used when immuno-gold labelling studies are required for TEM.