Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCLA engineers develop faster method to detect bacterial contamination in coastal waters

03.03.2010
Method cuts testing time from a day or more to less than an hour

Currently, beachgoers are informed about water-quality conditions based on results from the previous day's sample. Scientists must collect samples in the field, then return to a lab to culture them for analysis — a process that takes a minimum of 24 hours.

Now, engineers from the UCLA Henry Samueli School of Engineering and Applied Science have sped up the process of analyzing bacterial concentrations to under one hour, through the development of a new in-field, rapid-detection method.

Since bacteria levels can change quickly in the water column, a one-day turnaround time simply isn't fast enough to adequately protect swimmers or prevent unnecessary beach closures, the engineers say.

This issue is especially pertinent in California, where gastrointestinal illness that can result from contact with contaminated beach waters has been estimated to cost Orange and Los Angeles county beach visitors between $21 million and $51 million per year in sick days and related issues.

Furthermore, California coastlines are subject to chronic water pollution problems due to sewage spills and urban runoff. Rainstorms in Southern California can further exacerbate this problem, as pollutants that have accumulated over time on street surfaces are suddenly flushed into our waterways and into the ocean.

Jenny Jay, UCLA associate professor of civil and environmental engineering, and Ph.D. student Christine Lee have advanced and tested a rapid method in marine and freshwater samples from beaches in Malibu and Santa Monica. To their knowledge, it is among the first viable in-field methods for rapid, portable fecal bacteria analysis. This research will be published in an upcoming issue of the Journal of Applied Microbiology and is currently available online.

Even for areas like the Southern California coast, which are close to state-of-the-art laboratories, transportation time, coupled with lab work, may mean that results often are not ready until the next day. With such a delay between sampling and results, the results may no longer be relevant due to the dynamic nature of water quality in beach environments.

The new rapid method represents a field-portable alternative to more expensive procedures, particularly where larger-scale, expensive equipment is not readily accessible. To decrease the time to determine results, the researchers have outfitted a portable kit to test samples for bacterial concentrations.

"We envision a tool that can be used by lifeguards to collect and analyze water samples throughout the day, providing beachgoers with up-to-date, near-real-time data on water conditions," Lee said. "This could also be useful in determining persistence of a bacterial contaminant after a pollution event, such as a sewage spill or a septic tank leaking."

"We are currently applying this method, in a new approach, to identifying contamination sources in which we can adaptively sample the environment in order to hone in on hotspots," Jay said.

The process uses magnetic beads conjugated to specific antibodies that identify and bind fecal bacteria that are used as standards for determining the safety of recreational waters, such as E. coli and Enterococcus.

After a few filtration and isolation steps, the sample organisms are lysed and treated with an enzyme that catalyzes a light-emitting reaction with target ATP, the energy currency of a cell. Cells break down ATP to obtain energy important for cellular processes.

Scientists can then determine bacterial concentrations based on how much light is released by using a luminometer, a device that detects light emissions.

The process is called covalently linked immunomagnetic separation/adenosine triphosphate quantification technique (Cov-IMS/ATP).

The paper's other co-authors are UCLA electrical engineering professor William Kaiser and John Griffith, Ph.D., a senior microbiologist with the Southern California Coastal Water Research Project.

For the Southern California coast, using this detection method could significantly inform source-tracking practices.

"UCLA's rapid-method work is very exciting," said Mark Gold, D.Env., president of the environmental group Heal the Bay. "It could result in faster notification of the public on the health risks of swimming at contaminated beaches and better protection of public health."

Jay's research group has also applied Cov-IMS/ATP in drinking and source waters in Dar es Salaam, Tanzania, as part of the Environmental Protection Agency's People, Planet, Prosperity (P3) initiative, which promotes innovative designs for sustainabe resource use. The Tanzania project, which focuses on waterborne illness, contamination and hygiene behavior, is being conducted in partnership with Stanford University civil and environmental engineering professors Alexandria Boehm and Jenna Davis. Recent and future work for Jay's group also involves application of this method in beach water samples in Tijuana, Mexico.

The UCLA Henry Samueli School of Engineering and Applied Science, established in 1945, offers 28 academic and professional degree programs, including an interdepartmental graduate degree program in biomedical engineering. Ranked among the top 10 engineering schools at public universities nationwide, the school is home to eight multimillion-dollar interdisciplinary research centers in wireless sensor systems, nanotechnology, nanomanufacturing and nanoelectronics, all funded by federal and private agencies.

For more news, visit the UCLA Newsroom and follow us on Twitter.

Matthew Chin | EurekAlert!
Further information:
http://www.ucla.edu

More articles from Life Sciences:

nachricht At last, butterflies get a bigger, better evolutionary tree
16.02.2018 | Florida Museum of Natural History

nachricht New treatment strategies for chronic kidney disease from the animal kingdom
16.02.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

Im Focus: Autonomous 3D scanner supports individual manufacturing processes

Let’s say the armrest is broken in your vintage car. As things stand, you would need a lot of luck and persistence to find the right spare part. But in the world of Industrie 4.0 and production with batch sizes of one, you can simply scan the armrest and print it out. This is made possible by the first ever 3D scanner capable of working autonomously and in real time. The autonomous scanning system will be on display at the Hannover Messe Preview on February 6 and at the Hannover Messe proper from April 23 to 27, 2018 (Hall 6, Booth A30).

Part of the charm of vintage cars is that they stopped making them long ago, so it is special when you do see one out on the roads. If something breaks or...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Fingerprints of quantum entanglement

16.02.2018 | Information Technology

'Living bandages': NUST MISIS scientists develop biocompatible anti-burn nanofibers

16.02.2018 | Health and Medicine

Hubble sees Neptune's mysterious shrinking storm

16.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>