Mar 21

The stress of competition: a novel cortisol assay

case study_blood sweat tearsStress biomarkers, such as cortisol, are often used to monitor the effectiveness of an athlete’s training regime. However, levels of cortisol change quickly following exercise and so need to be monitored trackside to determine whether an athlete needs to be rested or whether they can train further and harder the next day.

Researchers at LGC have developed a unique new assay for detecting both free and total cortisol within human serum using a transportable platform technology. In collaboration with the English Institute of Sport, the assays were evaluated using blood samples from athletes (pre- and post-training) at Loughborough University via a pin prick to the finger.

Our approach successfully eliminates the need for sample processing and reduces the analyte incubation to minutes, negating the need to transit samples to laboratories and providing athletes with further information (percentage active cortisol).

This may in the future provide more robust results for athletes on which to base their training decisions and help increase the return on investment on the hundreds of millions of pounds spent on UK elite athletes.


Read our recent paper to discover how we transferred this assay across to a portable Raman platform in collaboration with Centre for Molecular Nanometrology at the University of Strathclyde:

Read our case study to find out more.


Gracie K, Pang S, Jones GM, Faulds K, Braybrook J, Graham D. Detection of cortisol in serum using quantitative resonance Raman spectroscopy (2017) Anal Methods 9:1589-1594. DOI:10.1039/C6AY03296F


LGC, the UK National Measurement Laboratory and Designated Institute for chemical and bio-measurement

Mar 15

Nitrate in infants’ vegetable food

Nitrate is a natural contaminant present mainly in vegetables and drinking water although it is frequently added as a preservative in processed meat products. Plants utilise nitrogen from the environment as part of the nitrate cycle, for their metabolism and to produce protein. Any excess quantity of nitrate is stored mainly in green leaves.  In particular, green leafy vegetables like rocket, spinach or lettuce can store high levels of nitrate with concentrations affected by the weather conditions (light, temperature) excessive fertiliser use and the type of soil.

The European Commission Regulation (EC) No 1881/2006 sets maximum levels for nitrates in some leafy vegetables (<7000 mg/kg) and processed cereal-based foods and baby foods for infants and young children (<200 mg/kg).

Baby food: organic green broccoli and spinach puree

Leafy vegetables have the highest median value of nitrate content. In an EFSA report (2008), the highest nitrate value was found in an oak-leaf lettuce sample from Norway (19925 mg/kg). For rucola, 56% of the samples analysed gave values over 4500 mg/kg. In baby food, the nitrate levels are much lower and according to Rebelo et al. (2015), the highest level was observed in retail, vegetable-based baby foods, with a maximum of 129 mg/kg. Several different analytical methods are used for the analysis of nitrate in foods and beverages including Ion chromatography, Spectroscopic methods and HPLC-Conductivity or other detector.

Nitrate on its own is non-toxic, however the conversion of nitrate to nitrite and N-nitroso compounds can potentially be dangerous for human and especially infant’s health, although some of the other metabolised nitrogen compounds may have positive effects (e.g. nitrogen monoxide- anti-hypertensive effect). According to the IARC Monograph (2010) ingested Nitrate and nitrite under conditions that result in endogenous nitrosation is considered “probably carcinogenic to humans” (Class 2A).

The physiology of babies and infants is very different to adults and it is important to control the type of substances ingested via foods and beverages. It is very common for mashed or pureed fruit and vegetables either home prepared or from the market to be fed to babies during the first months of their life. The process of conversion of nitrate to nitrite is accelerated when the vegetables are pureed; therefore the production of infant pureed food at home and improper storage conditions of any purchased baby vegetable food can potentially be dangerous to a baby’s health. The primary health concern is methemoglobinaemia, otherwise known as blue-baby syndrome as nitrite is able to oxidise haemoglobin resulting in reduced oxygen transfer around the body.

The European Food Safety Authority (EFSA) published a report in 2010 about the possible public health risks for infants and young children from the presence of nitrates in vegetables and according to this, the nitrate levels in vegetables together with the consumption data is not a health concern for most children. However, according to the same report, the risk to babies and infants 1-3 years old eating more than one spinach meal a day cannot be excluded.

To allow your laboratory to show with confidence, the quality of your analysis in measuring nitrate in infant vegetable food, LGC Standards has introduced sample 798 to the food chemistry proficiency testing scheme.


Application form

Sample 798 is available in round FC252 to be despatched on the 18th of April 2017. For more information please see Scheme Documentation or to participate, please complete the application form and return it to


EFSA Panel on contaminants in the food chain (CONTAM), ‘Scientific opinion of the Panel on Contaminants in the Food Chain: Nitrates in vegetables’, EFSA Journal, 689, 1-79:, 2008. (accessed 27 February 2017)

EFSA Panel on contaminants in the food chain (CONTAM), ‘Scientific opinion: Statement on possible public health risks for infants and young children from the presence of nitrates in leafy vegetables’, EFSA Journal, 8(12):1935-, 2010., (accessed 27 February 2017)
International Agency for Research on Cancer (IARC) , ‘ Monograph on the evaluation of carcinogenic risks to humans, Ingested Nitrate and Nitrite and Cyanobacterial Peptide toxins’, Volume 94, 2010,,   (accessed 23 February 2017)

By Savvas Xystouris, Technical/Development Manager, Proficiency Testing, LGC

Mar 13

Are your assay values below specification?

“The result I’ve found for the assay value in my API or finished dosage form is below my specification. Is there a problem with my reference standard?” is a question often asked by users of pharmaceutical reference materials. Some may even assume that there has been some degradation with the reference material they have applied.

12290805 Pills Pharma Drugs MulticolouredHowever, only in rare cases can a finding like this be related to an issue with the reference standard. And certainly it cannot be linked to a normal degradation of the standard at all, because in such a case you would rather find an assay value too high for the analyte in question…..

These issues are covered in greater depth here and are also a theme of LGC’s upcoming seminar.

Don’t forget you can keep up with other blogs from LGC’s Standards teams here.

Mar 02

Celebrating 25 years of Food Microbiology Proficiency Testing

LGC’s QMS Proficiency Testing (PT) scheme began 25 years ago, and had a very humble start in life, originally sharing premises with a manufacturer of under-wired bras!

Twenty five paper sign over confetti. Vector holiday anniversary illustration.

Back then reporting was done on an Analyst Request Form (ARF) which was sent out with the samples and then the data was posted back or faxed in. But in 2009, Proficiency Online Reporting and Trend Analysis (PORTAL) was introduced, providing secure, web based reporting, with fast access to results submission, reports and interactive trending tools across all LGC PT schemes.

QMS (Quality in Microbiology Scheme) has since established itself as a market-leader in terms of sample range, number of participants and geographical spread.

Fortunately the environment has also improved for the better, as we moved into new custom-built premises in 2012.

QMS offers a comprehensive programme of microbiology PT samples, covering a full range of microorganisms of interest to the food and dairy industries, including pathogens, indicator organisms and spoilage organisms.  Our participants appreciate the frequency and flexibility of our PT schemes, along with the user-friendly reports and rapid reporting times.

LGC was one of the first UK PT providers to gain UKAS accreditation in July 2002 and our accreditation number is 0001.

During the past 25 years, LGC’s microbiology production team in Bury has prepared and tested over a million PT samples. The scheme continues to grow steadily (as seen in the graph below), and in 2016, QMS sample sales hit 20,000 for the first time in its history.

QMS 25y

Lots of the ideas for new samples and matrices come from our participants, and we would like to thank you for all your feedback and loyalty over the years.

Please keep your suggestions coming and here’s to the next 25 years…

Feb 23

Monitoring mercury: measurements to make air cleaner

Air pollution across the EU accounts for more than 400,000 premature deaths and 6.5 million people falling ill each year. It causes significant damages to our natural environment, with almost two thirds of our ecosystems threatened by the effects of air pollution.

It is often the primary air pollutants – e.g. nitrogen oxides, sulphur dioxide and particulate matter – that are first brought to mind when considering air pollution. However, other air pollutants, such as the heavy metal mercury, are highly toxic and can cause severe damage to human health and the environment.

The UNEP Minamata Convention (signed in 2013) is a global treaty designed to protect human health and the environment from the adverse effects of mercury, providing, for example, control measures on its release into the environment. In order to understand the on-going effects of mercury on humans and the environment it is crucial to be able to accurately measure these levels to assess concentrations and trends.

laser ablation-1At LGC we have been working with other European measurement institutes as a partner in an EU-funded project (known as EMRP ‘MeTra’) to help provide the measurement infrastructure to support current EU legislation, ensure the quality and comparability of mercury measurement results and underpin advanced analytical techniques of the future. As there are currently no EU-approved methods for mercury in air, we have developed a high accuracy, direct analysis method using inorganic mass spectrometry combined with laser ablation (LA-ICP-MS) to support the current EU methods. This has been applied to real-world environmental samples (air filters) from rural and urban environments.

These results will feed into the UK and EU committees on air quality (BSI EH/2/3, CEN TC264) and will help to provide the evidence base for the next generation of standard methods for air quality assessment.


Following on from the success of this project, a subsequent project (Metrology for oxidised mercury) was funded by EMPIR in 2016 under the challenge ‘metrology for environment’ to further address this challenging issue. This project will start this summer (2017).


For more information on our work in this area please contact us.


For information on LGC’s Air PT scheme, please click here.


LGC, the UK National Measurement Laboratory and Designated Institute for chemical and bio-measurement

Feb 08

Is food allergen analysis flawed?

Food allergy is an increasing problem for those affected, their families or carers, the food industry and for regulators. The food supply chain is highly vulnerable to fraud involving food allergens, risking fatalities and severe reputational damage to the food industry.

A selection of nuts on a wooden spoonIt is understood that food allergy affects  up to 10% of children and 2-3% of adults – sometimes, tragically, with fatal outcomes – yet allergens remain challenging to analyse accurately, and are thus difficult to control.

Backroom lab difficulties seldom make headlines so it was exciting news when the Royal Society of Chemistry emailed to say our paper “Is food allergen analysis flawed? Health and supply chain risks and a proposed framework to address urgent analytical needs” was one of the top 25 most downloaded articles published in the Analyst in 2016. Our ‘grand vision’ in the paper, is

  • bioinformatics studies to pin down relevant markers or allergenic proteins within allergenic foods
  • development of reference methods for these allergens
  • appropriate reference materials which can ultimately support threshold decisions.

Thresholds are ‘limits’ that help decide if a food is safe or not safe for people with allergies (see section 6 of this excellent guide from the European Academy of Allergy and Clinical Immunology) but a crucial aspect of control is the ability accurately to test for allergens in foods to manage and police thresholds.

Our recommendations in the paper are complex, with associated resource demand, but rarely has such an exciting interdisciplinary scientific endeavour arisen as a solution to a key socially relevant problem.

Interest in this issue is building. I also recently spoke at an international conference on this topic, delivering two talks on food fraud and allergy.


Submitted by Michael Walker.

Jan 31

10 million people will die of bacterial infections in 2050, and each year after that


Article by: Ed Siegwart 


Antibiotic awareness

European Antibiotic Awareness Day (EAAD) took place on 18 November, in the middle of World Antibiotic Awareness Week and reminded us of the shocking statistic that if no new antibiotics are successfully developed then 10 million people will die of bacterial infections in 2050, and each year after that – we still are facing this terrifying statistic if new antibiotics are not developed.


LGC supports the antimicrobial drug pipeline



Use of antibiotics

Antibiotics aren’t just for treating infections. They are given to cancer patients, HIV sufferers and other immunocompromised patients to prevent complications during their primary treatment. Antibiotics are also given to the majority of patients before surgery, to prevent them getting a potentially lethal infection; without them surgery has to be carried out under even more tightly controlled circumstances, and even then patients remain highly susceptible to post-operative infections. They are also given to expectant mothers before childbirth to prevent post-natal infections.

Antibiotics are a modern medical miracle, because they cure the diseases they treat. Tuberculosis, gonorrhoea, strep throat, chest infections, boils, acne, wound infections, stomach ulcers, diarrhea, tooth abscesses, pneumonia, scarlet fever, anthrax, plague, mastitis and styes, to name a few, are all curable thanks to these ‘magic bullets’.


Antibiotic resistance

However, antibiotics have stopped working. Bacteria have evolved ways of coping with antibiotics, and we are helping them. In the past, Doctors overprescribed antibiotics, or issued them when not required; the more we use them, the quicker resistance occurs. Patients do not always finish the full course of antibiotics they are given, actively selecting for, and encouraging the survival of resistant bugs. Significantly, despite clampdowns and better awareness of the problem in recent years, antibiotics are still being used as a growth promoter in animal farming, increasing resistant bug numbers, which then move into the environment and humans. These are just a few ways we are spoiling the pot.

The antibiotic industry has woken up to the danger, and is kicking into gear, but new drugs will not reach the market for 10-15 years. Even when a company bravely dips its toe into the market to produce a new drug, there is an incredible rate of attrition to make it through clinical trials, and drugs which start development rarely make it to market. The easy to make, easy to develop drugs have already been made, and the bugs are already resistant.


Progress with antimicrobials

We are still awaiting good news, although progress is being made behind the scenes. We still have a shortfall of new classes of antimicrobials to tackle the most resistant and most dangerous pathogens. The lowlight of the year was the announcement of the identification of mcr-1 in pigs in China, which has now been found globally. This gene confers resistance to the last line antimicrobial colistin, and with that, we are now living in a world where some infections are untreatable. This, added to the publication of a case study in the US of a woman who died after becoming infected with a strain of K. pneumoniae resistant to all 26 antibiotics which could possibly be used to treat it (I’m confident that this is only the tip of the iceberg), means the fabled post-antibiotic era has arrived.

Infections caused by the multidrug resistant strains of bacteria are still rare. However, they are sharply increasing and, as illustrated by mcr-1, spread rapidly.


What can we do to help with antibiotic resistance?


  1. When offered antibiotics, ask why they are being prescribed to you, and ask if you would get better without them. Often the answer is that ‘yes you will get better’, and they are only being offered ‘just in case’. In those circumstances, you might want to consider saying ‘no thank you’, to preserve these drugs for when we really need them, or more likely, for when your children need them.


  1. Make sure you are aware of the facts. LGC held the Great British Tea Party to raise money for Antibiotic Research UK, which raises awareness of the issues surrounding antibiotic resistance, and works to develop new treatments.


  1. Tell everyone! If we can continue to raise awareness among the general public, then the message will spread and we can better tackle the problem – because it is all of our problem.


Discovery and development of antimicrobials

LGC works to support the antimicrobial drug pipeline, from high throughput screening and drug development to clinical trial support and on into surveillance. Our experts work to guide compounds through the process, gathering data on MIC, time-kill, drug activity and other antimicrobial efficacy tests, to identify lead molecules and target organisms.


To find out more, please view our webinar on In Vitro Antimicrobial Efficacy Testing: Potential Pitfalls and Future Methods”, where Ed Siegwart, Senior Scientist at LGC, discusses current testing methods being carried out at LGC and the ‘Next Gen’ methods in development, which will be used in the detection of AMR.


View LGC webinar on In Vitro Antimicrobial Efficacy Testing: Potential Pitfalls and Future Methods


Article by: Ed Siegwart 

Jan 27

Securing UK borders: the measurements making you safer

The increasing threat posed by terrorism is one of the major challenges facing UK border security [2015 UK Government National Security Risk Assessment].

When you or your luggage is screened as you pass through an airport, it will typically be done using an ion mobility spectrometer (IMS). This is well-established technology: in 2004 alone there were over 10,000 explosive detectors based on IMS used at security checkpoints around the world. IMS has low detection limits, is small, robust and inexpensive and gives real-time results, enabling luggage and passengers to continue to move quickly through security.

case study_securing UK bordersHowever, to ensure current and future risks are identified as early as possible, further technologies are required to complement the current screening techniques. One such
potential option is transportable mass spectrometry. Recent advances – instrumentation is smaller, cheaper and more efficient and extensive laboratory sample preparation is no longer required – have overcome previous barriers to industry adoption. It has become appropriate to evaluate the measurement performance of these technologies to further improve the detection of explosives.

LGC scientists have investigated the measurement challenges associated with transportable mass spectrometry for use in the field for counter-terrorism activities. This knowledge has been shared with national security stakeholders to support the implementation of improved policy and procedures to ensure continued high accuracy screening.

The work done by LGC to improve measurement accuracy of current equipment and ensure appropriate adoption of novel technologies will improve the detection of explosives and chemical weapons at UK borders and will help safeguard the UK from further terrorist attacks. This will protect lives, property and infrastructure, and avoid disruption to businesses and travel, while also improving confidence in public safety.


Read out latest case study to find out more.


LGC, the UK National Measurement Laboratory and Designated Institute for chemical and bio-measurement

Jan 18

Helping to feed the world with Genotyping by Sequencing

Many areas critical to improved agricultural production require robust and scalable genotyping platforms to enable the mapping of traits in plants and livestock as part of marker assisted selection (MAS) and marker assisted breeding (MAB) programmes.

Pile of Red Tomato.

Such programmes have helped improved drought, frost and parasite resistance in plants and improved yields.

Historically, these projects have involved the sequencing of parental genotypes using whole genome shotgun (WGS) sequencing. However, this can prove prohibitively expensive and resource intensive due to the complexity of sequencing de novo genomes.

In contrast, genotyping by sequencing (GBS) is a unique and cost-efficient technique developed and patented by Keygene, which reduces the genome complexity to certain regions which can be sequenced for a large number of samples.

According to Wolfgang Zimmermann, Sequencing Business Manager, Genomics, LGC – the scale of the efficiency increase is hard to comprehend; GBS delivers a large number of the useful SNPs in all samples of an analysed batch at just 1% of the cost – significantly opening up new applications and species.

Having secured a license for the commercial offering and use of GBS technology across all species and geographies, our sequencing experts have been working hard to further optimise the technique. This has led to the development of a self-tuning variant of the GBS technique (normalised GBS, or nGBS) that enhances the efficiency of the process and ensures selected loci are reliably sequenced across large sample batches using next-generation sequencing (NGS).

nGBS makes use of a normalisation process developed by LGC to exclude sequences for conserved repeats that code for organelle such as chloroplasts and mitochondria. This normalisation process is applicable to any genome regardless of size, methylation pattern, and type as well as abundance of repetitive elements.

This enables deeper sequencing of the remaining DNA and increases the number of single nucleotide polymorphisms (SNPs) identified from around 15,000 to up to 50,000.

Following a bioinformatics analysis, these SNPs can then be used to develop genotyping arrays or PCR- and KASP- based panels for downstream applications.

Zimmermann was keen to stress that if high quality DNA can be extracted then the technique can be used for nearly any species. Fortunately, LGC’s DNA extraction group have made a name for themselves extracting purified high molecular weight DNA from even the toughest of samples.


To learn more about LGC’s GBS services, and to downlown our latest application note visit here.

Jan 13

Toy Safety: proficiency testing to ASTM F963-16

On 20 October, 2016 ASTM International published ASTM F963-16 Standard Consumer Safety Specification for Toy Safety, an updated version of ASTM F963-11. The aim of this revision is to address various issues relating to toy safety, ideally highlighting and eliminating many potential hazards from toys intended for use by children under the age of 14.

baby toys collection isolated on white

A significant number of updates have been introduced to strengthen this standard, through the design, manufacturing and marketing of children’s toys, as well as addressing possible hazards that that may not be immediately apparent to consumers.






The following proficiency testing (PT) samples allow you to monitor your analysis against the 2016 version of ASTM F963 and EN71 equivalent where applicable:


Area updates ASTM Clause EN71 equivalent PT Sample Available in round(s)
Projectile toys 4.21 and 8.14 4.17 12 TY069 & TY071
Battery operated toys 4.25 15 TY070
Heavy elements 4.3.5 3 All rounds
Magnets 4.38 and 8.25 4.23 14 TY070
Sound producing toys 4.5 4.20 13 TY070 & TY072

For more information on our toy testing PT scheme please see Scheme Documentation.

To participate in any of the rounds please complete the Application Form and email it to

To order a copy of the standard ASTM F963-16, please visit the ASTM website.

By Wayne Gaunt, Technical Manager, Proficiency Testing
LGC Standards

Source:  ASTM F963-16, Standard Consumer Safety Specification for Toy Safety, ASTM International, West Conshohocken, PA, 2016,

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