The Agricultural Research Service of the USDA uses a Quorum Cryo-SEM preparation system for the study of mites, ticks and other soft bodied organisms

Dr Gary Bauchan is the Director of the Electron and Confocal Microscopy Unit at the Agricultural Research Service (ARS), the principal in-house research agency of the United States Department of Agriculture. The Unit is a core facility with the responsibility of providing collaborative assistance to scientists from ARS, Northeast Area and Beltsville Agricultural Research Center (BARC) who have microscopy applications that require high resolution imaging. Dr Bauchan’s team have produced images using electron microscopes of bacteria, fungi, mites, insects, nematodes and parasites along with plant and animal tissues both healthy and diseased. One of his major collaborations is with Dr Ron Ochoa, the world’s expert on plant feeding mites.

Biological specimens require special treatment due to the high water content of the samples. Many of the specimens are in liquid cultures or are very soft-bodied and by using classical preparative techniques will either destroy the specimen or distort the specimen producing artefacts. A cryo-prep system is an ultra-fast method to ready the specimens for observation in a SEM especially a high resolution field emission SEM. Thus, specimens are frozen in time to allow for observation of feeding behaviour, mating behaviour, host/parasite interactions, etc. It preserves the natural orientation of ultrafine structures such as setae, antenna, legs, skin texture, sensory organs, waxy coatings and eggs.

Asked about his experience using a Quorum PP2000 Cryo-SEM preparation system on the Hitachi S-4700 field emission scanning electron microscope, Dr Bauchan said “The Quorum system is easy to use, the set-up for imaging is logical, durable, reliable, and maintains ultra-low temperatures for a long period of time. Holders containing pre-frozen samples are transferred into the cryo-prep chamber where they are etched to remove any surface contamination (condensed water vapour) by raising the temperature of the stage from -130 ºC to -90 °C for 10-15 minutes. Following etching, the temperature inside the chamber was lowered below -130 °C, and the specimens were coated with a 10 nm layer of platinum using a magnetron sputter head equipped with a platinum target. The specimens were transferred to a pre-cooled (-130 °C) cryo-stage in the SEM for observation.”

The system has been used in multiple projects by the Unit, many of which have been published with the generation of stunning, colourful images. The use of low temperature SEM has been shown time and again to be the best method for the examination of microscopic biological specimens and their ultrastructure. The work in conjunction with Dr Ochoa has been particularly productive with five papers published this year to date. These have focused on the field of acarology, a branch of zoology dealing with the study of mites and ticks.


Above image: Gary Bauchan, Director, Electron & Confocal Microscopy Unit, USDA-ARS inserts mite specimens into the Quorum PP2000 Cryo-Prep Chamber (photo courtesy of Steve Ausmus, USDA-ARS, d3713-1)

Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the USDA.


The Biomedical Imaging Unit at the University of Southampton uses Quorum coating system as a general purpose work station

The Biomedical Imaging Unit (BIU) is a core facility, which provides a diagnostic and research service in high quality/high resolution microscopy. It is a joint facility run for the benefit of, and jointly funded by, the University of Southampton and Southampton University Hospitals NHS Trust with eight full time staff.

The microscopes in the Biomedical Imaging Unit are used extensively for research, teaching and diagnostic work by staff and students across the Trust and University with some 100-150 users per year from most science faculties including Medicine, Physics, National Oceanographic Centre, Engineering and Biological Sciences. This nationally important unit is extremely well equipped with two new microscopes to enable it to do 3D microscopy in addition to the existing transmission and scanning electron microscopes, confocal and time lapse light microscopes, image analysis and video microscopes.

The Quorum Q150T ES coater was purchased to replace a very old (1960s vintage) Edwards coating unit. It is being used as a general purpose workstation for carbon coating, sputter coating for high resolution SEM, glow discharging grids, cleaning apertures etc.

Discussing the purchase, Anton Page, Head of the BIU, says, “We looked at various competitive systems but these did not fit our needs nor matched our price constraints. The new coater is ideal. It is a combined system providing both sputtering and carbon coating. The deposition heads can be swapped in seconds and the intelligent system logic automatically recognises which head is in place and displays the appropriate operating settings.”

“Furthermore, for us, it is very fast! Our old coating unit took half a day (really!) to pump down before we could use it. The Q150T ES is a turbo pump system and can do the same job in 10 – 15 mins and get a better result. Newer coating units are obviously also much quicker than our old one but this is much more versatile – it has interchangeable head inserts – one for carbon coating and one for sputter coating which prevents cross-contamination of specimens, making cleaning easier too. It is simple to use and so we can teach our users how to coat their specimens instead of doing it for them.”

The Quorum Q150T ES is one of a family of coaters designed for applications across the spectrum of electron microscopy. Thousands of Q150 and Q300 coaters are used in EM laboratories around the world - and increasingly for many thin film coating applications.


Patricia Goggin from the University of Southampton working with the Quorum Q150T ES coating system (l). A transmission electron micrograph of immuno-gold labelled amyloid beta fibrils (r) prepared by Savannah Lynn

The Institut Charles Sadron at the CNRS-University of Strasbourg uses the Quorum Cryo-SEM preparation system for research in polymers and self-assembled systems

The Quorum PP3010T's ability to provide stable temperature regulation of samples ensures the facility gets the highest resolution when imaging delicate materials.

The Institute Charles Sadron is a CNRS-Institute located at the University of Strasbourg and performs fundamental and applied research on polymers and self-assembled systems. Dr Marc Schmutz works in the Electron Microscopy facility where he uses a Hitachi SU8010 Ultra High Resolution Field Emission Scanning Electron Microscope in conjunction with a PP3010T Cryo-SEM preparation system from Quorum Technologies. It is used to study a broad variety of materials from crystalline polymers to dragonfly wings. It is vital to be able to observe samples in, as close as possible to, their native state, either hydrated or in organic solvents.

Describing his choice of cryo-preparation system, Dr Schmutz says, “We picked the Quorum system because of its stable temperature regulation; each part of the system is independently controlled (cold stages and cryo-shields). This makes sure we will get the highest resolution when imaging our delicate materials.”

Examples of this work are shown in a recently published paper in the ACS Journal of Physical Chemistry where the drying mechanisms in plasticised latex films are studied with respect to their horizontal drying fronts. The drying kinetics of latexes with particles made progressively softer by adding increasing amounts of a plasticiser, in relation to speeds of horizontal drying fronts and particle deformation mechanisms are reported. [1] To examine the extent of particle deformation inside the dry films, a special sample holder was designed and built, allowing us to take cryo-SEM images of a cross section. Samples of the film were cut out with a razor blade, then fixed in the holder and rapidly plunged into liquid nitrogen slush (in the Quorum PP3010T PrepDek). After introduction into the preparation chamber, the films were then freeze-fractured at −150 °C with a cooled scalpel blade under high vacuum and coated with a thin layer of platinum. They were subsequently imaged in the SEM. 

The PP3010T is a highly automated, easy-to-use, column-mounted, gas-cooled Cryo-SEM preparation system suitable for most makes and models of SEM, FE-SEM and FIB/SEM. 



Left: Quorum PP3010T Cryo preparation system (left) mounted on Hitachi SU8010 FE-SEM at ICS-CNRS-unistra.

(Above: Latex film at high water content vitrified with the Quorum PT3010T. Small arrows point to the latex beads and the longer ones to the water area. (unpublished work))




Reference

1   Drying Mechanisms in Plasticized Latex Films: Role of Horizontal Drying Fronts, V. Divry, A. Gromer, M. Nassar, C. Lambour, D. Collin, and Y. Holl, J. Phys. Chem. B, 2016, 120 (27), pp 6791–6802. DOI: 10.1021/acs.jpcb.6b03009

The Sainsbury Laboratory at the University of Cambridge uses Quorum Cryo-SEM preparation system for research in plant biology

The Sainsbury Laboratory Cambridge University (SLCU) is a new research institute funded by the Gatsby Foundation. The aim of the Laboratory is to elucidate the regulatory systems underlying plant growth and development.

The Laboratory hosts a state-of-the-art advanced imaging facility for scientists working on several aspects of plant developmental biology, including live imaging of developing plant tissues, and high-resolution scanning electron microscopy.The facility currently has four major instruments, two stereo-fluorescence microscopes and several dissecting microscopes. 

Dr Raymond Wightman is its Microscopy Core Facility Manager. Studying plants using scanning electron microscopy (SEM) was a challenge. Prior to having a Quorum PP3010T Cryo-SEM preparation system, the lab would look at fresh plant samples that dried up and were hard to maintain while doing SEM. There was an urgent requirement for something to enable better imaging of fully hydrated plant tissue.

Asked about his experience using the Quorum PP3010T Cryo-SEM preparation system on the Zeiss EVO HD cryoSEM, Dr Wightman said “We have been impressed with the low maintenance costs and excellent applications support from the Quorum team. The system is now an integral part of the microscopy facility at the Sainsbury lab and because of the superior results we are getting now compared to before, the SEM use has gone up from about 8 hours per month to 64 hours per month. We are also able to process samples that we could not easily do prior to getting the Quorum kit.”

The system has been used in multiple projects by the Laboratory. These have included looking at the following: wood ultrastructure and cellulose organisation; observing cellular membranes; making new biocomposites and studying their properties; studying the interactions between a plant pathogen and the plant cell; studying cuticular wax formation; determining how plant cells coordinate their growth across tissues e.g. leaves and flowers. A final project on the development and structure of leaves from alpine plants where 90% of the work was performed on the PP3010T will be published shortly. All of these serve to illustrate the versatility of the Quorum cryo-SEM preparation system.





Dr Ray Wightman loads a biological sample via the Quorum PP3010T Cryo-SEM preparation system mounted on a Zeiss EVO HD cryoSEM. The image above shows yellow broccoli, cryo-prepared and platinum coated (5nm coating). Individual cells are clearly shown. (122x magnification).


The College of New Jersey use the Quorum Cryo-SEM preparation system in a project to study ice crystals in high altitude clouds

A Quorum PP3010T is helping to advance the understanding of the physical role of ice crystals.

Dr Nate Magee is an associate Professor of Physics at The College of New Jersey (TCNJ) where he leads a team working to advance the understanding of the physical role of ice crystals in processes with high altitude clouds.  Cirrus clouds are primarily composed of ice crystals that interact with solar radiation and IR radiation from the ground, and they play a significant, but still poorly understood role in Earth's climate.  The precise shapes and textures of these cirrus ice crystals largely determine how solar radiation interacts with the clouds (i.e. reflection & scattering angles) but the microscale structure is still fairly uncertain.  Dr Magee is working with the Quorum PP3010T cryo preparation system to make high-resolution images, 3D reconstructions and statistical measurements of ice crystals that are grown in the lab under cirrus conditions as well as ice crystals that are collected and recovered directly from high altitude cirrus using weather balloons and robotic cryo-capture.

A cryo preparation system is vital to the success of these studies. Describing the work, Dr Magee says, “Keeping ice crystals very cold (sub -150 C) means that their vapour pressure will be sufficiently low that their shape and surface structure can be "locked" in place as we image and analyse the ice particles.  Working at Peltier cooling stage temps (maybe to -50 C) would not make this possible.  The Quorum PP3010T transfer and interlock setup on our Hitachi SEM (with a few custom modifications on our part) has made it possible to transfer crystals from our lab systems directly into the SEM for imaging without exposing them to warmth or excess water vapour.”

So why did Dr Magee select the Quorum cryo-preparation package? “I have used Peltier cooling stages with FEI SEMs, which actually do have a few advantages for some types of in-situ ice growth experiments.  However, as I have said, we required sub -150 C temperatures for this study so, after considering what was available, we chose to work with Quorum.  Their full cryo temperature range and interlock prep chamber works very well for transfer experiments.  We are still working to develop its functionality for in-situ dynamic experiments on growing ice.”

This work is being presented in July at the International Conference on Clouds and Precipitation in Manchester.1,2

References

1 Magee, N.B., K. Boaggio, L. Bancroft, M. Bandamede, and K. Hurler, 2016:  Cryo-Scanning Electron Microscopy of Captured Cirrus Ice Particles.  Abstract #565, 17th International Conf. on Clouds and Precip. Manchester, UK, July 2016. 


2 Bancroft, L., K. Boaggio, K. Hurler, M. Bandamede, and N.B. Magee, 2016:  Comparative analysis of lab-grown ice crystals by Cryo-Scanning Electron Microscopy.  Abstract #566, 17th International Conf. on Clouds and Precip. Manchester, UK, July 2016.




Diamond Light Source use Quorum Cryo-SEM preparation system in conjunction with a new beamline

Diamond Light Source use a PP3000T cryo preparation system to help align protein crystals prior to X-ray macromolecular crystallography experiments.

Dr Anna Warren is a Senior Support Scientist on VMXm, a new beamline currently under development and construction at Diamond Light Source where it will be used to carry out X-ray macromolecular crystallography experiments.  Diamond offers 26 separate beamlines to aid with research groups in the UK and abroad, allowing them to determine the three dimensional structure of matter, such as protein molecules, on the atomic scale.  This can help to aid with drug design and to assist in the understanding of how these proteins function.  There are several beamlines already running at Diamond which allow the study of protein crystals ranging from 5-100 microns in size. However, as the systems get more complicated, inherently the crystals get smaller, so the beamline currently being built will allow the study of crystals ~500 nm to 5 microns in size. 

Due to the small size of these crystalsDr Warren is using a JEOL SEM to visualise the crystals and align them to the X-ray beam to carry out the experiments. The crystals are very fragile and prone to dehydration. This means they have to be stored, handled and studied at liquid nitrogen temperatures. This is where the Quorum PP3000T cryo-SEM preparation system has been of great useDr Warren takes up the story: “It has allowed us to visualise crystals less than a micron in size at cryogenic temperatures. This technique has never been used in our field in this way so we are currently carrying out a lot of research to understand the best ways of handling and preparing samples to obtain the best quality images. This would be impossible without having the Quorum preparation system and cryo-stage as the crystals would deteriorate in quality. Quorum was very helpful when we started looking at systems to purchase, especially as they have an SEM and cryo-SEM set up in Laughton. We were able to test out our samples in advance to get an understanding of whether it would work for us. Since making our purchase decision, we found that the preparation desk/slushing station have become a vital part of our sample preparation and this has been invaluable for our experiments.  

The image above illustrates the data quality we get routinely – crystals of cytoplasmic polyhedrosis virus (CPV20). The crystals shown here are in the size range 2.5 to 5 µm. 



The Quorum PP3000T cryo-SEM prep system mounted on a JEOL SEM at the Diamond Light Source



GloQube update

We are delighted to announce that the first production batch of GloQubes has been dispatched to customers.

The GloQube is a compact, fully automated glow discharge system used for the hydrophilisation (wetting) of TEM grid support films and other applications include the modification of surfaces, for example, for the enhancement of polymer bonding.

In addition to the wetting of TEM grids, the GloQube vapour chamber is designed for hydrophilic/hydrophobic (negative or positive) conversions, typically using reagents such as methanol and alkylamine. 

Pictured is our hard working production and final test team, from left to right: Richard, Darren, Adam, Steve and Pete.

For further information and product brochure download visit: GloQube product pages.

Quorum 2015 distributor of the year

Nanjing Tansi Technology Co. Ltd named a distributor of the year

Quorum Technologies is delighted to announce that our Chinese representative Nanjing Tansi Technology Co. Ltd (Tansi) has been named our Distributor of the Year for 2015.

 "The commitment, hard work and professionalism of our worldwide distribution continues to be vital to the continued success and growth of our business,” explained Tony Larkin, managing director of Quorum.

Tony continued, "This year’s award recognises Tansi's strong sales performance over a number of years, but also the excellence of the support that they give to their growing customer base. This applies equally to bench top EM preparation equipment  and to technology-leading cryo-EM preparation systems where they offer a complete sales and support package – including local installation and customer training across China".

The image shows Sunny Bin, sales manager at Tansi, receiving the award from Tony Larkin during the recent distributor meeting at Laughton.

Based in Nanjing and with an office in Beijing, Tansi is a specialist a supplier electron microscopy instrumentation. Please see this link for further information.

Introducing the GloQube - a new glow discharge system for TEM grids and surface modification

The GloQube is a compact, easy to use glow discharge system used for the hydrophilisation (wetting) of TEM grid support films. Other applications include the modification of surfaces, for example, for the enhancement of polymer bonding


The GloQube® is available in two formats. The GloQube-D has two independent vacuum chambers: a clean chamber for applications requiring hydrophobic/hydrophilic conversion, typically using air as the process gas, and a vapour chamber designed for hydrophilic/hydrophobic (negative or positive) conversions, typically using reagents such as methanol and alkylamine. The GloQube-S has a single clean chamber.

With operator safety and ease of use firmly in mind, the vapour delivery system has reusable septum-sealed reagent vials, which insert into a shielded needle using a simple bayonet fitting.

Each chamber can accommodate two 25 x 75 mm glass microscopes slides and automatic valving between chambers maintains cleanliness by preventing cross-contamination. A convenient draw-style chamber door, stage and removable sample trays ensure rapid sample exchange. Both GloQube-D and GloQube-S require a single vacuum pump giving a typical pump time to operational vacuum of around 60 seconds.

Data input and control is by an intuitive touch screen which allows multiple users to rapidly input and store preferred process “recipes”. Typical default glow discharge protocols are loaded as standard.

Like all other Quorum Technologies products, the GloQube® comes with a generous three-year warranty and dedicated specialist support.

For further information, including product brochure download visit: GloQube® product pages.

Quorum excel at the Super Growth awards

We were delighted to be named as a finalist in the Sussex Super Growth Awards for 2016, which took place at the American Express Community Stadium, Brighton on 8th March.

There are over 21,000 companies in based in Sussex - a thriving district in the south east of England -  and these awards aim to congratulate the top 60 companies in the county who have achieved significant growth and contributed to the economic success and prosperity of the area. To make the list businesses have to show significant and sustained grown over four years. Quorum achieved a commendable 34th position with a growth rate of 54% and our parent company, Judges Scientific, 13th position with an impressive growth of 95%.

Quorum Technologies’ managing director Tony Larkin says that this is external recognition of the hard work that everyone at Quorum has put in over the past four years. 

"In that time we have moved into new premises, grown revenues and continued to expand our activities and the support we give to our world-wide customer base".

The image shows Quorum's commercial director Bob Hennig (centre) and marketing director Mike Wombwell receiving the award.