Automated assays for rapid mass screening and detection of bacteria and toxins in food, lead to economic and health benefits
Submitting InstitutionUniversity of Strathclyde
Unit of AssessmentAllied Health Professions, Dentistry, Nursing and Pharmacy
Summary Impact TypeTechnological
Research Subject Area(s)
Technology: Medical Biotechnology
Medical and Health Sciences: Medical Microbiology
Summary of the impact
Professor William Stimson has led research into rapid diagnostic tests
for the food industry from
1996 to the present day. These tests reduce the time for microbiological
testing of food pathogens
from 2-5 days to within a working day. The new technology is fully
automated, uses less material
and involves fewer manipulations than previously available kits, leading
to a reduction in cost and
time. A spin out company, Solus Scientific Solutions Ltd., has attracted
funding for further Research & Development, and has created 24 jobs.
Sales of testing kits
produced revenue of £3.4 million by year end 2012, and have increased
since this date.
The prevention of food poisoning is a major concern in every country, but
poor food hygiene,
bacterial infection and fungal mycotoxins are commonly regarded as far
more of an issue in
developing nations than diseases such as cancer or autoimmune disorders.
In developed countries
there is compulsory testing for food pathogens, mycotoxins and meat
speciation, and the supply
chain from producer to sales is strictly governed by regulations. In
developing nations the lack of
regulation and testing is compounded by lack of refrigerated food storage.
Mycotoxins are present
in around 25% of foods worldwide and are associated with many diseases and
disorders — one of the species, aflatoxin B1, is recognised as the most
substance. Of the food poisoning bacteria, Salmonella and Listeria are the
most recognised and
cause millions of people to be ill every year. However, E coli 0157.H7 is
now becoming a major
concern, especially in meat products, and legislation is being introduced
throughout the developed
Key research findings
The original research concepts  aimed to develop an assay platform that
was highly sensitive,
stable, simple and inexpensive for bacterial detection. In the food
industry, the microbiological
regulations indicate the need to detect as little as one single organism
in 25 grams food. In order to
detect such low levels of contamination bacterial numbers must be grown to
a detectable level.
The more sensitive the assay, the less time is required for bacterial
growth, and hence the overall
time of diagnosis depends on both processes. Research conducted by Stimson
led to a major step
forward in reducing the overall assay time, while not increasing costs by
making the following
- Developing a novel broth that allowed bacterial growth at the fastest
possible rate: Bacterial
growth media were investigated systematically to understand precisely
what each of the
components did (some components had been introduced over almost a 100
years). It was
found that many were unnecessary, their concentrations were sub-optimal
and that some
compounds actually inhibited the organism we wished to grow rapidly.
Thus a single broth was
developed (instead of the normal 2 broths required) that would grow even
organism up to our detection level of 500 bacteria in a few hours
instead of 40+ hours, and
would do this even in the presence of 10 million competing organisms
- Providing highly selective monoclonal and polyclonal antibodies
against specific sequences in
the bacterial cell wall: Immunisation protocols have been designed using
subtype additives or pharmacological suppression that result in enhanced
recognition of the
carbohydrate sequences of importance. In addition, hybrid animals with
responses are also employed to respond to minor antigens. The origins of
these protocols are
recorded in [2, 5 and 6].
- Defining a detergent that reduced the bacterial cell wall into the
smallest units possible, thus
providing the greatest numbers of detection entities.
- Using a novel flash chemiluminescent molecule for the detection: This
dioxitan derivative has
enhanced stability and light output [1 and 4].
- Providing a dedicated luminometer at 10% the cost of existing
instruments and adapting
Dynex microplate automation systems for our assays.
This research supplied all the information to allow the mass
microbiological screening of food
products to be made achievable within the one working day (if required).
This allows customers to
obtain fresher foods and removes the need for expensive refrigerated
holding facilities, which are
required while waiting for assay results i.e. early release of product
with a longer shelf life is
Key researchers: The research was carried out by William Stimson
(Professor of Immunology at
the University of Strathclyde during the period 1983 - 2013) and David
Cowan (Optics and
Instrumentation — Nephlar Electronics).
References to the research
1. Stimson, W.H. Complying with food legislation through immunology:
antibodies and immunoassays, the next generation. In "Food Quality and
Safety" (Sim, T.S.
and Yeow, K.P., eds.), SSM & SIFST, Singapore (1993) pp. 7-32.
Note on quality: Invited Plenary Lecture, The Singapore Institute
of Food Science and
Technology (SIFST). This research output formed a part of the 1996 RAE
Immunology that gained a 5*.
2. Ferro, V.A. and Stimson, W.H. Immunoneutralisation of gonadotrophin
a potential treatment for oestrogen-dependent breast cancer. European
Journal of Cancer, 33,
Note on quality: This is a high impact cancer journal (5.1)
3. Stimson, W.H. and Taravati, M. Characterisation of anti-Escherichia
antibodies for use in diagnostic assays. Food and Agricultural Immunology,
11, 61-73 (1999).
Note on quality: This is unique journal dealing almost exclusively
with antibody-based assays
in the food industry.
4. Ronald, A. and Stimson, W.H. The evolution of immunoassay technology.
117, S13-S27 (1998).
Note on quality: A special edition of this highly rated journal. An
invited, peer-reviewed article.
5. Rahman, S. and Stimson, W.H. Characterisation of monoclonal antibodies
for the core oligosaccharide of Shigella lipopolysaccharide.
Hybridoma, 20/2, 85-90 (2001).
Note on quality: Peer reviewed paper that is commonly cited as
prior art in responses to patent
applications claiming specific anti-bacterial antibodies.
6. Khan, M.A.H., Ferro, V.A. and Stimson, W.H. Use of a highly specific
against the central variable amino acid sequence of mammalian
hormone to evaluate GnRH-1 binding sites in adult male rats. American
Reproductive. Immunology., 48, 1-10 (2002).
Note on quality: Journal ranked 7th in all reproductive
biology with a 3.4 impact factor.
Additional evidence for quality of research
The research has led to a granted patent — Compositions and methods for
the rapid growth and
detection of microorganisms. W.H.Stimson. International Patent Application
WO 2010/029360. A patent `Compositions and methods for the rapid growth
and detection of
microorganisms. W.H.Stimson. United Kingdom 2463369' has been granted.
Details of the impact
Process from research to impact
The Company Solus Biologicals Ltd. was initiated in 2007 by Stimson and
Cowan, supported by a
SMART grant award from Scottish Enterprise to produce prototype
instrumentation for the assays
based on the prior research conducted by Stimson. During its second year
of life Anglo Scientific, a
UK investment group, took a particular interest in funding the developing
technologies and in 2009
Solus Scientific Solutions Ltd. evolved to take these to market, with a
Physics graduate of the
University of Strathclyde as Chief Executive Officer.
Types of impact
- The impact of this research has been initially economic, with
expansion of the original spin
out company, investment leading to employment and product development,
and profit to the
company from sales of testing kits.
- The food testing kits offer significant advantages to the producers,
supermarkets supplying food in the UK, over previous testing systems.
- The final impact is on the health of the public due to improved
testing for mycotoxins, and
other products which will detect food spoilage.
Commercially successful spin out company
The food sector represents the largest market segment within the
industrial microbiology market
and represents almost 50% of the total market for food pathogens such as
Listeria, Salmonella and
E.coli. Europe is a substantial market for food microbiology testing. With
a population of more than
500 million (2009), the 27 countries of the European Union (EU) performed
an estimated 275
million food micro tests in 2011 [Sources A and B]. In mid-2011, Solus
absorbed a significant sales and marketing diagnostic company, RayAl Ltd,
to initiate full
production and sales of its products on a wider basis. RayAl sells
extensively in the UK, France
and Denmark. [Source C] The products marketed by this company are assays
Listeria, E coli 0157.H7, meat speciation and a number of mycotoxins
tests, as well as the broths
essential for bacterial culture. The Solus-developed test-kits and
antibodies were all developed
from the Strathclyde research and account for significant sales and
projections, based on current
levels suggest they will account for 65/70% of the turnover of this
company by 2014.
Investment into assay development
A Scottish Enterprise SMART grant for £100,000 was awarded in May 2010 to
assist in the
development of the rapid (20 hour) Listeria monocytogenes test,
which is expected to be the first to
comply with present EU legislation. An initial Eurostars grant of
€1.36million was awarded in July
2011, to fund the full development of the 5 hour abattoir assay and assist
its uptake throughout the
EU, by the introduction of the appropriate legislation. The system
incorporates Salmonella and E.
coli 0157.H7 assays into a robot-based process that will automatically
test beef, pork and sheep
carcasses before release to the public. Trials of the robotic system,
based on the principle of the
automated cow milking system, are reaching an end-point in abattoirs in
France and Denmark
(July 2013). However, it will take time to assist the EU in accepting
individual carcass meat testing
A final investment round to raise £800k was closed successfully in
January, 2013. This is being
used in part to develop 8 mycotoxin assays for food and crop monitoring
using immunoassays and
lateral flow devices. — the latter are particularly useful for assessing
risks associated with lorry
deliveries of grain where tests should be completed in 15 minutes to allow
rapid unloading. The
monoclonal antibodies for these have already been produced in Strathclyde
University and have
been licenced to Solus Scientific Solutions Ltd.
Solus Scientific Solutions Ltd converted its market for the major
Assays (ELISA) for Salmonella and Listeria to the Strathclyde research
based products in July
2013. This followed the successful completion of 2 full AFNOR
Accreditation Trials for both
products in June 2013. [Source D]. Association Française de Normalisation
(AFNOR) is the French
national organisation for standardisation.
AFNOR is the EU body that provides certification for the
food industry and conducts rigorous audit of any product before it can be
marketed [Source E]. The
E. coli assay is currently on trial (June 2013) to be completed by the end
of the year.
From 2011, with the acquisition of RayAl Ltd. food testing kits were sold
across UK, France and
Denmark. The market share available to Solus products was 2.5m test kits
in 2011, and growth is
expected. Solus is currently in discussions to provide tests to countries
such as India (with plans to
set up a sales office), where food safety is of particular importance.
Revenue received by Solus Ltd
was £1.1 m for the first quarter of 2013, representing a 43% increase over
same time period
(January-March) 2012. Sales of testing kits produced revenue of £3.4
million by year end 2012.
Sales have increased since this date and the figure is predicted to be
£5.1 million by end 2013.
Public Health and Consumer Benefits
By July 2013 the companies utilising the Solus assays based on Strathclyde
Eurofins, Marks and Spencer, RHM, Cargill, Iceland, Premier Foods and
Alcontrol. Eurofins, for
example, is the world leader in food and feed testing [Source F], offering
a comprehensive range of
state-of-the-art analytical techniques to global food suppliers, including
the rapid diagnostic testing
for salmonella [Source G]. The other companies listed are distribution and
with global reach. Cargill is an international producer and marketer of
food, agricultural, financial
and industrial products and services. This company employs 140,000 people
in 65 countries
[Source H]. Other companies have extensive reach throughout the UK (Marks
Iceland). These companies conduct rigorous testing of their own food
product ranges, or are
companies which conduct testing on behalf of other companies to meet
hygiene standards. Their
testing, based on Strathclyde research, will have direct health benefits
to consumers throughout
the UK, Europe and globally.
24 jobs have been created from Solus start-up in 2007 to July 2013, and
will increase as sales
Reduced costs and increased efficiency
The assays developed from the Strathclyde research are constructed closely
on systems that have
formed the basis of modern immunoassays. Hence, little additional user
training is needed and no
expensive additional assay materials are required other than those
available `off the shelf' — thus,
this can be reflected in a very competitive selling price resulting in a
percentage cost reduction of
around 50% from existing high sensitivity testing products. Additionally,
the assays may be fully
automated using Dynex machines (these are leased to customers) and can
assay up to 200 food
samples per hour. These improve quality control of testing as well as
reducing the staff numbers
required and the need for highly trained scientists. In addition, the
standard test for Listeria takes 2-5
days, whereas the rapid test produced by Solus is completed in 22 hours.
Sources to corroborate the impact
market report titled "Food Micro — 2008 to 2013", the worldwide rapid
testing food microbiology
marketing in 2008 represented over 738 million tests with a market value
in excess of $2.06 billion.
Europe is a substantial market for food microbiology testing. With a
population of more than 500
million (2009), the 27 countries of the European Union (EU) performed an
estimated 275 million
food micro tests in 2011.
Solus Scientific Solutions Ltd. website.
AFNOR accreditation for Solus Ltd Salmonella and Listeria assays
and http://www.afnor.org/. AFNOR
(Association Française de
Normalisation) website. AFNOR is the premier organisation in Europe for
the validation and
certification of food diagnostic assays.
Rapid food testing
for Salmonella by Eurofins
Information on the size of Cargill.