Stuart discusses his role in the School of Chemical and Process Engineering ‘Our goal as a unit is to perform world leading research. This is only possible by having cutting edge equipment supported by experts in the field.’

Stuart says ‘As we are a user facility that services the whole university and external universities, our current work varies significantly from day to day. We are currently working on cryo serial sectioning on self-assembling peptide & chondroitin sulphate hydrogels which aid cartilage growth in knee joints, which is a collaboration between biological engineering and mechanical engineering here at Leeds.

Quorum first installed a PP3010 at Leeds Uni in April 2017, and we have successfully partnered with them across multiple projects.  Stuart says of the Quorum equipment ‘Our Quorum PP3010 is currently the only cryo-SEM equipment in the university, so it is a key part of the research performed. It is reliable, easy to use and is stable enough to perform not only high-resolution imaging but also FIB cutting. We have specifically requested the Quorum P3010 to be installed on our new system with will be delivered at the end of the year. We also have a Quorum carbon coater which is extensively used for high-resolution coating of SEM and TEM samples.

We asked Stuart what the main benefits of the PP3010 cryo-prep system, ‘The main advantage of the quorum system is flexibility. It’s very convenient to be able to fracture, sublime and coat in the same system, and to be able to sublime before quickly checking if the features of interest are revealed then continue to sublime if not. The resolution of the SEM doesn’t seem to be affected by the cryo system, as it is quite important to obtain good quality, high resolution images.

We wanted to share some of these images with you from this exciting project, and we look forward to helping many more customers with these systems in the future (images supplied by Leeds University).

We have linked a couple of the projects relating to the images below.

Lead sulfide scaling in multiphase systems and co-precipitation in the presence of calcium carbonate – ScienceDirect

Springtails are extraordinary creatures, they are arthropods living in soil, plants and decaying material adapted to the environment by developing a special comb-like pattern on their skin. This rhombic-hexagonal structure is responsible for the non-wetting properties of the springtail body.

Sample: springtail colony from orchid bark. Sample preparation and imaging from Anna Walkieicz: bio preparation protocol followed by Critical Point Drying (K850 CPD) and coating with 8nm of Pt (Q150V S plus).

Pollen are small bioaerosol grains consisting of a single cell containing two male gametes essential for sexual reproduction of flowering plants. Typically, these bioaerosols range from 10 to 200 μm, are aerodynamic and low in density. These characteristics are essential for wind-pollination (anemophily) and/or insect-pollination (entomophily) – the transport of pollen from male stamen to the female stigma.

The grain wall is comprised of a tough chemically stable substance known as sporopollenin, which is highly resistant to environmental damage. It is punctuated with small openings called apertures which allows the male gametes to escape during pollination.

Pollen is typically classified by its distinctive structural features, i.e., variation in size, shape, number of apertures and surface texture, which also makes it possible to identify and classify a plant at family and genus level, and often even species level.

Anemophilous (inconspicuous or non-flowering) plants typically produce enormous quantities of very lightweight pollen grains, usually with air-sacs. Whereas entomophilous (insect-loving) plants produce pollen that is relatively heavy, prickly, and sticky to cling to the insects attracted by the flowers’ nectar and showy colours.

SEM micrographs of pollen grains below are from a Papaver Nudicaule (Iceland Poppy) and a Geranium (Wild Purple Cranesbill) plant image imaged using a FE-SEM prepared using the Quorum PP3010 cryo-preparation stage by Dr Mark S. Taylor.

Imaging Spotlight. 

Diatom algae:
One of the most sophisticated frustule structures.
Sample preparation:
Biological tissue processing followed by critical point drying using Quorum Technologies K850 CPD and 8nm Pt coating in Q150VS Plus. Imaged by Dr Anna Walkiewicz, Applications Specialist

To all our customers, suppliers and partners, I hope that you, your family and friends are safe and well. As the effects of the CoViD-19 outbreak are felt more acutely across the world, I wanted to let you know about the measures that Quorum Technologies has put in place to counter the impact of the pandemic on our business and what we are doing to support users of Quorum equipment during this difficult time.

Press release: 4 December 2019, Judges Scientific plc