Carbon Nanotubes Detect Lung Cancer Markers in the Breath

November 2008

Using an array of nanotube devices, each coated with a different organic material, researchers at the Israel Institute of Technology have developed diagnostic system that may be able to diagnose lung cancer simply by sampling a patient’s breath. The results of this study, which was led by Hossam Haick, Ph.D., appear in the journal Nano Letters.

Dr. Haick and his collaborators first created individual devices consisting of random networks of single-walled carbon nanotubes coated with 1 of 10 different insulating nonpolymeric organic materials. The investigators used standard microprocessor fabrication techniques to create the sensors. Thanks to the different organic materials used to coat the nanotubes, each sensing device provided a unique response when exposed to wide variety of the more than 200 volatile organic chemicals present in human breath.

To calibrate the devices, the investigators captured the breath of 15 nonsmoking healthy patients and 15 individuals with stage 4 lung cancer. Next, they concentrated the organic compounds in each breath sample using a method known as solid phase microextraction and then analyzed each sample using gas chromatography-mass spectrometry (GC-MS). GC-MS is a highly accurate technique that is too expensive and time consuming to find use as a routine diagnostic assay. The researchers then ran the same samples through their sensor array; the electrical output of the test devices changed in a way that was characteristic of the exact mixture of organic compounds found in the breath samples.

From these data, the investigators were able to distinguish between two response patterns from each of the 10 array members. There was no overlap in the response patterns between the healthy and lung cancer patients in these first tests. The researchers are now testing their system on a much larger group of patients and healthy subjects.

This work is detailed in the paper “Detecting simulated patterns of lung cancer biomarkers by random network of single-walled carbon nanotubes coated with nonpolymeric organic materials.” An abstract of this paper is available at the journal’s Web site.

http://nano.cancer.gov/news_center/2008/nov/nanotech_news_2008-11-20c.asp

I checked 2 of APNT's patent filings - CLOSE!:

1) United States Patent Application 20070167832
Kind Code A1
Yaniv; Zvi ; et al. July 19, 2007
Analysis of Gases

Abstract

Systems and techniques for the analysis of gases for medical purposes are described. In one aspect, a system includes a sample collector to collect a physical sample associated with an individual and present a gas sample for analysis, a gas analysis device to analyze the gas sample presented by the sample collector to determine a concentration of one or more non-aqueous gases in the gas sample, a data storage device that includes information reflecting a correlation between concentration of the one or more non-aqueous gases in the gas sample and a disease state, and a data analysis device to determine a medical condition of the individual based on the concentration of one or more non-aqueous gases in the gas sample and the information.

Inventors: Yaniv; Zvi; (Austin, TX) ; Soundarrajan; Prabhu; (Austin, TX)
Source

2) United States Patent Application 20050244811
Kind Code A1
Soundarrajan, Prabhu ; et al. November 3, 2005
Matrix array nanobiosensor

Abstract

An apparatus for detecting multiple analytes comprising an array of nanobiosensors, each comprising a biological entity immobilized onto carbon nanotubes, wherein a plurality of the nanobiosensors in the array have unique biological entities, wherein a first one of the plurality of nanobiosensors has a first biological entity immobilized onto carbon nanotubes, and wherein a second one of the plurality of nanobiosensors has a second biological entity immobilized onto carbon nanotubes, the first biological entity is unique relative to the second biological entity.

Inventors: Soundarrajan, Prabhu; (Austin, TX) ; Ginsberg, Valerie; (Austin, TX) ; Yaniv, Zvi; (Austin, TX)
Source

University of Oklahoma Researchers Developing New Tool to Detect Cancer

8/27/2008 1:00:59 PM

Early cancer detection can significantly improve survival rates. Current diagnostic tests often fail to detect cancer in the earliest stages and at the same time expose a patient to the harmful effects of radiation. Led by Dr. Patrick McCann, a small group of internationally known researchers at the University of Oklahoma with expertise in the development of mid-infrared lasers is working to create a sensor to detect biomarker gases exhaled in the breath of a person with cancer.

Proof-of-concept detection of a suspected lung cancer biomarker in exhaled breath has already been established as reported by the Oklahoma group in the July 2007 issue of Applied Optics. The research was inspired by studies showing that dogs can detect cancer by sniffing the exhaled breath of cancer patients. For example, by smelling breath samples, dogs identified breast and lung cancer patients with accuracies of 88 and 97 percent, respectively, as reported in the March 2006 issue of Integrative Cancer Therapies. The evidence is clear—gas phase molecules are uniquely associated with cancer.

Intrigued by the concept of using breath analysis to detect cancer, McCann saw an opportunity to use mid-infrared laser technology to help elucidate the relationship between specific gas phase biomarker molecules and cancer. He believes it is possible to develop easy-to-use detection devices for cancer, particularly for hard-to-detect cancers like lung cancer. McCann says we need sensors that detect these gas phase cancer biomarkers. “A device that measures cancer specific gases in exhaled breath would change medical research, as we know it.”

McCann says the science and technology exist to support the development of a new tool to detect cancer, but the research will take from five to 10 years to get low-cost devices into the clinic. OU may have the strongest contingent of researchers dedicated to providing a solution to the problem using this approach. Even though studies confirm that dogs can detect cancer by smelling the gases, they can’t tell us what gases they smell. It’s up to the medical research community using the best measurement tools to figure that out.

According to McCann, “Improved methods to detect molecules have been demonstrated, and more people need to be using these methods to detect molecules given off from cancer. We have developed laser-based methods to detect molecules. Mid-infrared lasers can measure suspected cancer biomarkers—ethane, formaldehyde and acetaldehyde.” McCann will use nanotechnology to improve laser performance and shrink laser systems, which would allow battery-powered operation of a handheld sensor device.

“You often have to go outside your discipline to pioneer new areas of research and Oklahoma has an advantage with so many experts in other fields. But getting funding for interdisciplinary research is challenging. However, more capital and research infrastructure are needed for this device to become a reality. As we build upon our existing capabilities Oklahoma can become more widely known as a center of excellence in this important area.”

Even though McCann is not a cancer researcher, he wants his research on developing innovative laser technology to benefit the millions of people who would otherwise suffer from a late-stage cancer diagnosis. McCann knows it can be done. He says, “The science supports it, and the dogs tell us there is something there.”

Source

Laser light detects disease on the breath

Feb 22, 2008

Scientists could soon be diagnosing disease by using laser spectroscopy to analyse the gas molecules in a patient's breath.

Identifying molecules

An optical spectroscopy technique that uses a laser to detect molecules in the breath could help to diagnose diseases such as asthma or cancer. According to US researchers, they have improved a technique, known as cavity-enhanced direct optical frequency comb (OFC) spectroscopy, to be more sensitive and cover a larger spectral bandwidth. (Optics Express 16 2387)

"With our current system we can detect many tens of molecules with sensitivities near the 1 part per billion level," Michael Thorpe, a researcher from JILA, a joint venture between the National Institute of Standards and Technology and the University of Colorado, both US, told optics.org. "In the next 5-10 years I expect detection capability will extend further to the mid-infrared and the spectral bandwidth will increase to detect thousands of molecules simultaneously."

Why frequency combs?

OFC technology uses a modelocked laser to create broad spectral coverage. "Unlike single frequency laser systems, a frequency comb can detect many different molecules at the same time," commented Thorpe. "What's more, it is superior to mass spectrometer systems because it is better at distinguishing individual molecules, performs more rapid detections and is relatively inexpensive."

Whilst the idea of using frequency combs is not new, it has only recently been extended thanks to the availability of user friendly modelocked femtosecond fibre lasers. "These lasers can now be used to produce robust frequency combs capable of continuous operation without user intervention," commented Thorpe.

Thorpe's team uses a modelocked erbium-doped fibre laser that generates 100 fs pulses and covers a spectrum between 1.5-1.7 µm. By coupling these pulses into an optical enhancement cavity and using a virtually imaged phased array (VIPA) detector, a high spectral resolution of 800 MHz is achieved. "It is this unique combination of optical components that provides broad spectral coverage, high sensitivity and high resolution for analyzing complex gas samples," explained Thorpe.

Light detects breath molecules

The pulses of laser light were fired into an optical cavity, which contained the breath sample. The laser beam bounces back and forth within the cavity allowing the light to sample the entire volume. This increases the light-molecule interaction time, which in turn increases the sensitivity. By comparing the light coming out of the cavity with the light that went in, the JILA team could determine which frequencies of light were absorbed and by how much.

"Light transmitted from the cavity is dispersed into a two-dimensional pattern and imaged onto a camera by the VIPA spectrometer," explained Thorpe. "Computer databases and software compares the recorded spectrum against known molecular spectra to determine the quantities of the individual molecules contained in the gas sample."

Looking to the future

Apart from disease diagnosis via breath analysis, the approach could be useful for applications such as: monitoring of atmospheric greenhouse gases and analysing ice core samples for climate studies and detecting impurities in gases used to manufacture semiconductors.

The team expects clinical trials to be carried out in the next couple of years and plans to explore new laser systems, new types of optical cavities and new methods of detecting the transmitted light. "To reach its full potential, the device's spectral bandwidth and the number of molecules available for detection need to be increased by an order of magnitude," concluded Thorpe. "I'm fairly confident that the next generation system is just over the horizon."

About the author

Marie Freebody is a reporter for Optics & Laser Europe and optics.org.

http://optics.org/cws/article/research/33006;jsessionid=D328C6DB7DAE984126EDA2305D403726