Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New technique yields fast results in drug, biomedical testing

10.10.2014

A new technique makes it possible to quickly detect the presence of drugs or to monitor certain medical conditions using only a single drop of blood or urine, representing a potential tool for clinicians and law enforcement.

The technique works by extracting minute quantities of target molecules contained in specimens of blood, urine or other biological fluids, and then testing the sample with a mass spectrometer.


A new technique called slug flow microextraction makes it possible to quickly detect the presence of drugs or to monitor certain medical conditions using only a single drop of blood or urine. The technique involves drawing a specimen into a glass capillary that also contains an organic solvent and rocking the capillary back and forth several times to extract target molecules from the biological sample into the solvent. (Purdue University image/Weldon School of Biomedical Engineering)

Testing carried out with the technology takes minutes, whereas conventional laboratory methods take hours or days to yield results and require a complex sequence of steps, said Zheng Ouyang (pronounced Jung O-Yong), an associate professor in Purdue University's Weldon School of Biomedical Engineering.

"We've converted a series of operations into a single extraction process requiring only a pinprick's worth of blood," he said.

The method, called "slug flow microextraction," could be used to detect steroids in urine for drug screening in professional sports and might be combined with a miniature mass spectrometer also being commercialized. The combined technologies could bring a new class of compact instruments for medicine and research, Ouyang said.

Findings are detailed in a paper appeared online Oct. 5 in the research journal Angewandte Chemie International Edition. The paper was authored by graduate student Yue Ren, undergraduate student Morgan N. McLuckey, former postdoctoral research associate Jiangjiang Liu and Ouyang.

The researchers demonstrated the technique, using it to perform therapeutic-drug monitoring, which has potential applications in drug development and personalized therapy; to monitor enzyme function, as demonstrated for acetylcholinesterase, which is directly related to the symptoms and therapy for Alzheimer's disease; to detect steroids, yielding results in one minute; and to test for illicit drugs.

"In the future, for example, parents might be able to test their children's urine for drugs with a simple cartridge they would take to the corner drug store, where a desktop mass spectrometer would provide results in a few minutes," Ouyang said.

The technique involves drawing a specimen into a glass capillary that also contains the organic solvent ethyl acetate.

Like oil and water, the two fluids are immiscible, and an interface is formed between the specimen and the solvent. Gently rocking the capillary back and forth several times causes small amounts of target molecules in the biological sample to cross this interface into the solvent side without mixing the two fluids.

"You don't want to mix these two, you want to extract only the biomarkers you are looking for and leave the junk behind because mass spectrometry is very sensitive to impurities," Ouyang said.

Then the solvent containing the biomarkers is subjected to a high-voltage current, ionizing the sample so that it can be analyzed with mass spectrometry.

Researchers have used microextraction for other applications.

"I think this is the first time it has been applied to a biological sample for mass spectrometry," Ouyang said. "You just use a pinprick of blood, and the analysis is completed in minutes.”

When combined with the miniature mass spectrometer also developed at Purdue the method represents a mobile system for medical professionals, researchers and law enforcement.

Mass spectrometry works by turning molecules into ions, or electrically charged versions of themselves, inside the instrument's vacuum chamber. Once ionized, the molecules can be more easily manipulated, detected and analyzed based on their masses. The new approach uses a method called nanoESI – or nano electrospray ionization - in which the ionization step is performed in the air or directly on surfaces and does not require a vacuum chamber.

Although the research was conducted using a conventional laboratory mass spectrometer, the same nanoESI operation could be carried out with the new miniature mass spectrometer. Whereas conventional mass spectrometers are bulky instruments that weigh more than 300 pounds, Purdue researchers have recently completed their latest version of the miniature mass spectrometer, the Mini 12, which weighs 40 pounds, is 12.5 inches wide and 16 inches high.

"The sampling ionization technologies like slug flow microextraction could make the miniature mass spectrometers perform the actual testing without requiring other equipment for sample treatment," Ouyang said.  "This will bring a new class of compact medical instruments."

The research has been funded by the National Institutes of Health.

The work to develop the miniature mass spectrometer has been supported by the NIH and National Science Foundation and is led by Ouyang and R. Graham Cooks, the Henry Bohn Hass Distinguished Professor of Chemistry in Purdue's College of Science.

U.S. patent applications have been filed for the microextraction and miniature mass spectrometry. The technologies may be commercialized through a new company formed after partnership agreements were signed in 2013 by Purdue and Tsinghua University.

"The overall goal is to use this technology for developing disposable sample cartridges to work with our mini mass spectrometry system in clinical and especially the point-of-care applications in a doctor's office," Ouyang said. 

Writer: Emil Venere, 765-494-4709, venere@purdue.edu

Source: Zheng Ouyang, 765-494-2214, ouyang@purdue.edu   

ABSTRACT

Direct Mass Spectrometry Analysis of Biofluid Samples Using Slug Flow Microextraction NanoESI**     

Yue Ren, Morgan N. McLuckey, Jiangjiang Liu and Zheng Ouyang*

* Weldon School of Biomedical Engineering, Purdue University

** This research was supported by Nation Institutes of Health   

Direct mass spectrometry (MS) analysis of bioluids with simple procedures, such as using the ambient ionization, represents a key step for translation of MS technologies to the clinical and point-of-care applications. The current study reports the development of a single-step method using slug flow micro extraction and nanoESI (electrospray ionization) for MS analysis of organic compounds in blood and urine. High sensitivity and quantitation precision have been achieved for analysis of therapeutic and illicit drugs in 5 μL samples. Real-time chemical derivatization has been incorporated for analyzing anabolic steroids. The monitoring of enzymatic functions of wet blood has also been demonstrated with the cholinesterase. The reported development encourages the future design of highly functioning but simple devices, in replacement of traditional complex lab procedures for MS analysis of biological samples.

Emil Venere | Eurek Alert!
Further information:
http://www.purdue.edu/newsroom/releases/2014/Q4/new-technique-yields-fast-results-in-drug,-biomedical-testing.html

More articles from Medical Engineering:

nachricht Penn first in world to treat patient with new radiation technology
22.09.2017 | University of Pennsylvania School of Medicine

nachricht Skin patch dissolves 'love handles' in mice
18.09.2017 | Columbia University Medical Center

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>