UBC Researchers Develop Diagnostic Tool for Detecting Cryptosporidium

A handheld 'tricorder' that can test for biological contamination in real-time has been the dream of science fiction fans for decades. And UBC Okanagan engineers say the technology is closer to science fact than ever before.

Using a small and inexpensive biosensor, researchers in the School of Engineering have developed a novel low-cost technique that quickly and accurately detects cryptosporidium contamination in water samples.

Cryptosporidium is an intestinal pathogen and one of the leading causes of respiratory and gastrointestinal illness in the world. Drinking water contaminated with the parasite can result in diarrhea and, in extreme cases, can even lead to death.

“Current methods for detecting cryptosporidium require filtering large volumes of water, separating out the organisms, staining them with a fluorescence label and trying to identify the pathogen using a microscope,” says George Luka, a doctoral student at UBC Okanagan’s School of Engineering and study lead author. “The process is extremely slow, expensive and doesn’t yield reliable results.”

Luka says there is an urgent need to develop a fast, flexible, accurate and real-time detection tool to meet the challenge of protecting water consumers from this common and potentially dangerous contaminent.

To solve this problem, Luka and his colleagues tested a specially designed and calibrated biosensor. Using varying concentrations of pathogen in water samples, they were able establish its ability to detect cryptosporidium contamination.

“The biosensor performed exactly as we were hoping and was able to measure cryptosporidium contamination rapidly and without the need for complex preparations and highly-trained technicians,” says Luka. “This is an impressive solution that can easily be integrated into inexpensive and portable devices to test drinking water in real-time anywhere in the world.”

Luka also says the biosensor can be expanded to measure other biomarkers and hazards.

“The technology has real potential to be used to test all kinds of biological contamination, both in medical and environmental applications. A handheld sensor that tests the safety of our water and our environment could soon become a reality.”

The research was published recently in the journal Sensors and was funded by the India-Canada Centre for Innovative Multidisciplinary Partnerships to Accelerate Community Transformation and Sustainability (IC-IMPACTS).

Journal Reference:

George Luka, Ehsan Samiei, Soroush Dehghani, Thomas Johnson, Homayoun Najjaran, Mina Hoorfar. Label-Free Capacitive Biosensor for Detection of Cryptosporidium. Sensors, 2019; 19 (2): 258.

Irish Scientist Pioneers Research into Rapid Detection of Pseudomonas aeruginosa Infections

A Newbridge scientist has been awarded a grant of €419,000 from Science Federation Ireland to aid him in his pioneering research into  faster clinical detection and diagnosis of bacterial infections.

Dr Joseph Byrne, who currently works in NUI Galway said the grant will allow him to apply his research to new applications.

One of the infections that Dr Byrne researches and aims to combat is Pseudomonas aeruginosa, which is a common cause of death in sufferers of cystic fibrosis.

“My SIRG project will be built upon a foundation of carbohydrate chemistry, which I have been exploring during my postdoctoral research in Switzerland. While in Trinity I also worked on a project where I made compounds which hindered the growth of bio-films caused by bacteria linked to lung infections,” said Dr Byrne.

“I will carry out my research mostly in the School of Chemistry in NUI Galway. Additionally, I have collaborators in CÚRAM (SFI Centre for Medical Device Research) and in TU Dublin, whose labs I will visit to achieve key milestones in the project. The work will be carried out by me and a PhD student who I will recruit in the coming months. I also have a team of collaborators who have offered me some of their time and expertise to help me progress with my research,” he added.

Dr Byrne’s planned devices will be designed by means of 3D printing and will be programmed to operate in such a way as to detect the presence of specific bacteria through colour changes. These changes are caused by the interactions of their proteins with laboratory-produced sugar-based chemical compounds on the surface of newly-designed materials.

Dr Byrne also explained the importance of his progress and why he is determined to combat harmful bacterial infections: “Rapid diagnosis of bacteria is vital to inform appropriate medical treatment strategies and combat increasing antibiotic resistance globally. By providing a new methodology for rapid diagnosis of bacterial infection, my work will facilitate quicker decision-making on targeted medical treatment strategies for patients.

“In Ireland this would be particularly valuable for rapid diagnosis of  Pseudomonas aeruginosa  infections, a significant risk factor for cystic fibrosis patients (as well as others with compromised immune systems). More generally, helping clinicians avoid the use of broad-spectrum antibiotics would help combat the global challenge of increased antibiotic resistance,” he said.

Dr Byrne is a former pupil of  Scoil Mhuire Primary School and the Patrician Brothers Secondary School in Newbridge. He attended Maynooth University from 2006-2010, where he received his degree in Chemistry. In 2015, he then received his PhD from Trinity College in Dublin.

He is currently in Switzerland finishing a Marie Curie Research Fellowship in the University of Bern and will start his new venture with his planned devices in NUI Galway this April.

Hong Kong Researchers Develop Microrobots to Enhance C. difficile Toxin Detection

The Chinese University of Hong Kong said on Wednesday that its research team has recently developed microrobots that can detect Clostridium difficile bacterial toxins accurately within 15 minutes.

Clostridium difficile, aka C. difficile, is the most common hospital acquired enteric infection. The toxins secreted by C. difficile will cause diarrhea, fever and hematochezia. In some cases, patients may develop life-threatening peritonitis and sepsis.

Currently, the stool samples of hospitalized patients with diarrhea are being tested in the laboratory to determine the presence of C. difficile. The process normally takes one to two days.

The research team led by Li Zhang, associate professor of the university's Department of Mechanical and Automation Engineering, has developed fluorescent magnetic spore-based microrobots to shorten the detection time. These devices carry functionalized carbon dots that emit fluorescence, the intensity of which will gradually decrease during "on-the-fly" reaction with C. difficile toxins.

Furthermore, the unique and intricate three-dimensional architecture of the microrobots enables easy spreading and swarming in diluted stool samples. Such a continuous and efficient movement acts as active searching, thus facilitating higher detection efficiency and sensitivity than static counterparts.

This enables the reaction even if the sample has a low concentration of toxins. Also, when applying an external magnetic field, the microrobots can perform a controllable movement in the stool samples and be tracked with automation in an easy manner.

Zhang said that in the experiment, all the microrobots placed into stool samples infected by C. difficile no longer emit fluorescence in 15 minutes. This new motion-based detection technique provides a promising solution to the rapid clinical sensing to supplement, or potentially replace the current detection methods in clinic.

"This new technology eventually provides opportunities to develop a multiplex new quick-sensing system not only for C. difficile toxins, but also for many bioanalytical fields including food, chemicals and early diagnosis of other bacteria-infected diseases, " Zhang said, adding that the team will construct an automated microrobotic platform for practical diagnostic application that can be used in clinics and hospitals.

The finding has been published in Science Advances, a scientific journal of the American Association for the Advancement of Science.

DNA Rapid Test Simplifies Water Quality Assessment

At the TU Vienna, a simple method for the detection of health-endangering germs in water was developed. The DNA rapid test can be used directly on site without special knowledge and replaces expensive and time-consuming methods in the laboratory.

Contaminated water is one of the world’s greatest health risks. These are often fecal germs. In order to be able to solve the problem quickly, the cause of the germs must be found. In a test it can be determined whether the germs are from agriculture or waste water.

“Certain bacteria can only be found in the faeces of certain animal species,” explains Georg Reischer from the Technical University of Vienna. “If samples are examined for DNA sections of these bacteria, it is therefore possible to say exactly from which living organism the impurities originate. For example, there are bacteria that are typical of the intestinal microbiome of ruminants. If their DNA is found in a water sample, the contamination was probably caused by cows in the pasture.”

SIMPLE AND FAST

Appropriate testing methods are important to manage water quality and to support public health risk assessment. Until now, however, these were tied to the laboratory and limited by a lack of specialised equipment and trained personnel.

Reischer worked in a team at the Institute of Process Engineering, Environmental Technology and Technical Biosciences at the Vienna University of Technology for several years to research the simplification and acceleration of the process. The method should be reliable and also applicable without biotechnological knowledge. Now the technology is mature. The procedure takes two hours, does not require extensive practical training and the results reach the level of comparable tests. However, unlike quantitative approaches, the DNA rapid test provides only qualitative results.

EXPANDABLE METHOD

According to Reischer, the method works as simply as a pregnancy test: “The bacteria are destroyed, the DNA is selectively duplicated and then detected with a simple strip.” Another advantage of the method is that it can be applied to very different bacteria and viruses. Initially, however, the researchers are concentrating on detecting dangerous germs in water because this is a particularly common problem, said Reischer.

An industrial partner is now being sought for the development of a measuring instrument.

The research project was carried out within the framework of the Inter-University Cooperation Centre Water and Health. The cooperation partner was the Department of Agricultural Biotechnology Tulln of the University of Natural Resources and Applied Life Sciences in Vienna.

The article about the project was published in the journal Nature Scientific Reports.

bioMérieux Acquires Invisible Sentinel, a US-Based Company Specialized in Food and Beverage Molecular Testing

bioMérieux, a global player in in vitro diagnostics and world leader in food microbiology testing, today announced the acquisition of Invisible Sentinel Inc. This company, based in Philadelphia (PA) develops, manufactures and markets innovative and user-friendly molecular diagnostic tools for the rapid, accurate and reliable detection of pathogens and spoilage organisms in food and beverage.

Invisible Sentinel has developed Veriflow®, an innovative DNA Signature Capturing Technology that combines very simple protocols and workflows with rapid results, accuracy and specificity. This molecular testing platform is very easy to use and does not require sophisticated lab infrastructure. It targets diversified customers segments in the food and beverage industry (beer, wine, poultry, juices, nutraceuticals, etc.). The patented Veriflow® technology, which integrates innovative approaches based on conventional scientific principles, already has a proven market uptake with more than 1 million tests sold since its launch in 2014.

This acquisition strengthens bioMérieux’s position in food pathogen testing and spoilage organism detection by expanding it to new customer segments such as breweries and wineries. bioMérieux will now offer innovative alternatives to deliver accurate results for rare pathogen testing and challenging food matrices. The acquisition also complements bioMérieux’s molecular food testing solution GENE-UP® nicely and offers the opportunity to adapt Invisible Sentinel assays on the GENE-UP® system, making them available to customers processing high daily volumes of samples.

“We are very enthusiastic about having the talented team at Invisible Sentinel join us, and welcome them to bioMérieux,” said Nicolas Cartier, Executive Vice President, Industrial Microbiology Unit at bioMérieux. “This acquisition illustrates bioMérieux’s commitment to bring innovative solutions to customers of all sizes to ensure food and beverage quality and contribute to protecting consumer’s health.”

Dr. Nicholas Siciliano, Chief Executive Officer and co-founder of Invisible Sentinel, added: “We are thrilled to join the bioMérieux family today. bioMérieux’s rich history of pioneering innovation in diagnostics makes them the ideal partner for us to accelerate our growth. Their global commercial network and leadership in the food microbiology market will allow our products to reach even more customers worldwide while also empowering us to provide additional technologies and resources to our U.S. client base. Ultimately, this partnership will greatly enhance our ability to develop new products, introduce our technologies to new markets, and to better serve our existing customers in the food and beverage industry.”

bioMérieux has acquired all shares of Invisible Sentinel Inc. for approximately $75 million in cash, subject to customary adjustments. The company has 40 employees (FTE) and generated sales of about $9 million in 2018 with very strong double-digit growth year on year.

New Phenotyping AST System a Useful Tool in Antibiotic Resistance Battle

A next-generation phenotyping system is seeking to revolutionize antibiotic susceptibility testing (AST) in an effort to begin treating patients faster and to combat antibiotic resistance.

Developed by SeLux Diagnostics and detailed in a recent study in Scientific Reports, a scientific journal published by Nature, the new microplate-based surface area assay enables clinicians to prescribe targeted antibiotics up to 3 days faster than the current industry standard and also includes 60 different antibiotics in a single AST.

“We introduce a novel approach that allows phenotypic AST determinations for non-fastidious bacteria within 5 hours,” the investigators write. “After a 4-hour incubation in cation-adjusted Mueller-Hinton broth and antibiotic, this assay measures bacterial concentrations by binding a universal small-molecule amplifier to bacterial surfaces. Surface binding enables the method to account for bacterial morphological changes in response to antibiotics. Because this technique requires only a single, endpoint read, it should also enable larger antibiotic menus to be run for each patient sample.”

AST is not new; the technology has been around since the 1990s, but has not been modernized in years, explained Eric Stern, PhD, chief technology officer and co-founder of SeLux Diagnostics.

“[Although] revolutionary in their time, these automated platforms now fail to meet clinical needs in two critical dimensions,” Dr. Stern told Contagion®. “First, results arrive too slowly, and sample preparation requires too many days, to keep pace with cutting-edge ID techniques…Secondly, the antibiotic menus of conventional AST platforms are limited [and] tests can only be provided for 12-15 antibiotics at a time, which is insufficient to meet the demands of today’s resistant organisms.”

The AST constraints—namely, the long wait time—up until this point have led to clinicians using broad-spectrum therapies that can contribute antimicrobial resistance. Take sepsis, for example.

“Under the current paradigm of clinical care, septic patients are prescribed broad-spectrum antibiotics for a minimum of 3 days—and often 5 or more days,” Dr. Stern said. “This over-reliance on some of the best currently-available drugs directly fuels the rise of multidrug-resistant organisms.”

SeLux Diagnostics’ new AST assay seeks to close the gap between bacterial identification and AST.

“We sought to develop an assay that would enable rapid AST determinations but require only standard microplate processing hardware to perform,” David L. Smalley, PhD, president at American Esoteric Laboratories and a co-author of the Nature study, told Contagion®. “The surface area measurement concept provided the necessary accuracy. The small-molecule fluorescent probe provides the necessary signal amplification to enable the use of standard microplate readers, which should minimize costs and maximize throughputs.”

With this tool, health care providers will be able to personalize treatment plans by pinpointing specific antibiotics that will be most effective, Dr. Stern explained.

“Targeted antibiotics will not only more effectively kill the bacteria, but also lower the chance of it mutating and developing resistance,” he said. “In other words, the battle against superbugs can be improved with next-generation AST because patients will be transitioned to personalized, targeted therapies as quickly as possible.”

US Food and Drug Administration clinical trials are expected to begin in the second half of 2019, according to Dr. Stern.

Novodiag® CarbaR+ Test Allows Rapid Molecular Testing for Superbacteria and Associated Drug Resistance

Mobidiag Ltd., a commercial stage molecular diagnostics company addressing the spread of antimicrobial resistance, announced the CE-IVD marking of Novodiag® CarbaR+. Novodiag® CarbaR+ is a single molecular test allowing fully automated detection of Carbapenemase-Producing Enterobacteriaceae (CPE), and associated resistance markers. CPE are bacteria that are resistant to carbapenem class of antibiotics. In addition, Novodiag® CarbaR+ identifies a plasmid-mediated resistance to colistin. Colistin is considered the drug of last resort for many infections.

Novodiag® CarbaR+ combines multiplex qPCR and microarray testing in a single product allowing cost-effective and fast analysis of the most common CPE and colistin resistance markers. These bacteria may cause multiple antibiotics to perform inefficiently, which in turn can lead to serious infections, particularly in healthcare settings. The test is designed to run on-demand using the automated Novodiag® system, producing results in 80 minutes with less than five minutes hands-on time by an operator.

With two multiplex tests already available for screening antibiotic resistance (Amplidiag® CarbaR+VRE and Amplidiag® CarbaR+MCR), the new on demand Novodiag® CarbaR+ test will enable rapid patient screening for multidrug resistant organisms, helping to prevent their spread in a hospital environment, and enabling physicians to guide patient treatment accordingly.

Tuomas Tenkanen, CEO of Mobidiag, said, “Antimicrobial resistance is one of the most significant challenges to global health. Mobidiag is contributing to the fight against “super bacteria” by developing innovative diagnostic tools. Novodiag® CarbaR+ is our third test on the Novodiag® system and strengthens our offering in the fight against antibiotic resistance. Together with our Amplidiag® and Novodiag® tests, we offer comprehensive diagnostic solutions to a wide range of infectious diseases in both centralised and decentralised laboratories regardless of their size and patient volumes”.