PositiveID, a company out of Delray Beach, Florida, claims to have completed development of an implantable temperature-sensing microchip. The chip measures internal body temperature and uses RFID technology to communicate with an external reader. Somehow, the company thinks continuously monitoring body temperature will provide an early warning of onset of an illness. We don’t think many patients would appreciate implanting a chip just for this cause, but it is a nice proof of concept. It might prove useful in a few select patient groups with very weak immune systems, where it is important to detect infections in their earliest stages. However, the biggest potential lays in the sensors that PositiveID is still working on as part of their Wireless Body program: currently they are working on a glucose-sensing sensor called GlucoChip, which has huge potential for noninvasive glucose measurements for diabetics. We remain a bit skeptical, because we have yet to see the breath glucose meter, but we’ll be following on any developments. Regarding the temperature-sensing chip, although the company has finished development, there is no word on regulatory approval or availability yet.
Press release: PositiveID Corporation Completes Development of Temperature-Sensing Microchip…
Diagnostics Archives
Implantable Temperature-Sensing Microchip
Rapid DNA-Based Tuberculosis Test Has Results In Two Hours
Tuberculosis is still a huge global health problem, with the most frightening part perhaps being the multi-drug resistant strains of the mycobacterium. One obstacle which has hampered effective control of this disease, especially in poor countries, is the long time it takes to diagnose it. In these lower-income areas, the standard diagnosis of TB is by microscopy, but this does not give any information on drug-resistance – those cell culture tests take two weeks, by which time it might have spread to many other people.
A Swiss group, The Foundation for Innovative New Diagnostics, has come up with a better way. The sputum sample is first treated with sodium hydroxide and alcohol, killing any TB, and the sample is fed into a small device which analyzes the DNA and gives a simple report regarding the presence of TB and the resistance status of the organism. This shrinks the time-frame for diagnosis of multi-drug resistant TB from 2 weeks to 2 hours. The individual tests cost only $17, although the machine costs $17,000. This is a nice example of cutting-edge technology being scaled to low-cost applications in resource-poor areas.
iHealth Blood Pressure iPhone/iPod/iPad Dock
Medical devices that can be attached to iOS devices have been promised for a long time, but suddenly during the last few weeks some have actually started to appear. The latest addition is this BP3 dock, which acts like a blood pressure monitoring system for iPod touch, iPhone, and iPad. The system consists of a battery-powered docking station and a blood pressure arm cuff, which measures blood pressure just like common automated blood pressure measurement devices do which have been available for a long time. What this adds is a pretty graphical interface along with tracking and reports of blood pressure variability over time. Results can also easily be shared with a doctor and the app provides some basic explanations of the used terms and interpretation of results. The device can be ordered from the company’s website for $99.95 with the app downloadable for free.
Novel Biosensor Detects Fast-Spreading Viruses and Bioterror Agents
RNA virus infections are often diagnosed using polymerase chain reaction (PCR) tests, however technical requirements are high and sample preparation time can be long. For RNA viruses such as Ebola and Marburg, which could be used as bio-warfare agents, rapid diagnosis is a necessity. Researchers at Boston University have developed a new biosensor that directly detects live viruses from biological media with little to no sample preparation. From the press release:
The new biosensor is the first to detect intact viruses by exploiting plasmonic nanohole arrays (PNAs), or arrays of apertures with diameters of about 250 to 350 nanometers on metallic films, that transmit light more strongly at certain wavelengths. When a live virus in a sample solution, such as blood or serum, binds to the sensor surface, the effective refractive index in the close vicinity of the sensor changes, causing a detectable shift in the resonance frequency of the light transmitted through the nanoholes. The magnitude of that shift reveals the presence and the concentration of the virus in the solution.
Artificial Nose Based on DNA Technology Sniffs Out Organic Vapors
Stanford scientists are using the backbones of DNA and specialty fluorescent molecules to detect organic compounds in vapor. The technique relies on replacing traditional DNA nucleobases with one of seven fluorescent molecules developed at Stanford. These new nucleobases change color in the presence of certain organic compounds, providing an indication of what this new nose is ‘smelling’.
Florent Samain, a postdoctoral researcher in chemistry and lead author on the Angewandte Chemie paper, used DNA synthesis techniques to generate a library of all 2,401 possible ways that the seven substitute molecules could be combined in a string of four units.
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Nanosensors Detect Cancer Biomarkers In Exhaled Breath
Researchers at Technion – Israel Institute of Technology have shown that nanosensors can be effective in detecting certain types of cancer in exhaled breath. Pending further studies, it is hoped that this technology will be used for regular screening of patients as part of doctors’ appointments.
Exhaled alveolar breath was collected from 177 volunteers aged 20–75 years (patients with lung, colon, breast, and prostate cancers and healthy controls). Breath from cancerous subjects was collected before any treatment. The healthy population was healthy according to subjective patient’s data. The breath of volunteers was examined by a tailor-made array of cross-reactive nanosensors based on organically functionalised gold nanoparticles and gas chromatography linked to the mass spectrometry technique (GC-MS).
MIT Researchers Use Raman Spectroscopy for Noninvasive Blood Glucose Measurements
Researchers at MIT’s Spectroscopy Laboratory have announced that they are currently working on a Raman spectroscopy machine which can measure blood glucose without a blood sample. The machine sends infrared light through the skin to determine glucose levels in the interstitial fluid. In a paper published in the July 15 issue of Analytical Chemistry, the researchers described their algorithm for determining blood glucose levels based on the interstitial concentration.
From MIT’s press release:
University of Tokyo Researchers Testing Blood Sugar-Sensitive Fluorescent Hydrogel
While current medical technology allows diabetics to closely monitor and manage their blood sugar levels, most patients need to prick their fingers multiple times a day to obtain blood samples. Researchers at the University of Tokyo and the BEANS Research Institute hope they can change that with new fluorescent hydrogel beads which glow at different intensities depending on glucose concentration. The researchers are currently testing the beads in mice, and hope to have a product which can monitor blood sugar without any patient intervention within ten years.
From the University of Tokyo Magazine’s Coverage:
Akonni Biosystems Awarded Patent for its Method of Rapidly Extracting Nucleic Acids
Frederick, MD based Akonni Biosystems has announced issuance of a patent titled “Apparatus, system, and method for purifying nucleic acids.” The method described by the patent utilizes the company’s TruTip kits, which consist of pipette tips that contain a nucleic acid binding matrix in order to speed up the process of extracting DNA or RNA samples for PCR.
From the press release:
