Category: biochemistry

Epidermal Electronics

I have been recently reading a lot about epidermal electronics. Pretty soon patients in hospitals (and sports people) should be able to wear skin mounted electrodes to be able to measure a variety of physiological indicators in real time for a prolonged period of time.

The latest innovation comes from the University of Illinois. A new device looking like a tattoo, has been developed and proposed as an innovative smart skin solution. Researchers at the University of Illinois who came up with this device made circuits with a wide array of components, to prove it could work: sensors, LEDs, transistors, radio frequency capacitors and wireless antennas. The devices can draw power from induction or even from mini solar cells!

Inventors say they could be used for various medical applications, especially sensors that monitor heart and muscle activity, which currently require conductive gels and/or relatively bulky equipment. To prove it, they measured electrical activity produced by the heart, brain, and skeletal muscles, some data are reported in Science.

image You can also see a video of the technology below. Pretty impressive technology which will be hopefully available soon!

This is impressive technology, pushing the boundaries of wearable sensors and providing incredible possibilities for studying human movement.

(Example of a sensor setup for EEG and other measurements. Photo courtesy of Prof. John Rogers)

(Easy removal of the skin mounted electrode. Photo courtesy of Prof. John Rogers)

You can learn more about this and other technologies developed by Professor Rogers’ group here.

>Nanosensing and biochemistry


This is not really new…but it was new to me today when I found some articles on this innovative technology. I am talking about a nanosensor that could be injected into the skin, much like tattoo dye, to monitor an individual’s gluclose level. As the glucose level increases, the dye would fluoresce under an infrared light.

The researchers at Draper Laboratory, in Cambridge (MA), have already tested a sodium-sensing version of the device in mice, and are due to begin animal tests of the glucose-specific sensor.

The material consists of 120-nanometer polymer beads coated with a biocompatible material. A patent application has been filed. Within each bead is a fluorescent dye and specialized sensor molecules, designed to detect specific chemicals (so far the work has been done on sodium and glucose).

When injected into the skin, the sensor molecule pulls the target chemical into the polymer from the interstitial fluid. To compensate for the newly acquired positive charge of a sodium ion, a dye molecule releases a positive ion, making the molecule fluoresce. The level of fluorescence increases with the concentration of the chemical target.  The range of concentrations that the sensor can detect can apparently be varied, depending on whether it is important to measure precise concentrations or more broad variability.

The sodium sensor has shown early success in animals. The researchers have developed a glucose sensor that works via a similar mechanism. It has been shown to work in a solution but has not yet been tested in animals.

Still, the researchers have a long way to go before the sensor is ready for human testing. However, if it works and it is accessible, this could be a good way to make a good use of a tattoo 🙂



2011 WADA prohibited list is now online

The Prohibited List (List) was first published in 1963 under the leadership of the International Olympic Committee. Since 2004, as mandated by the World Anti-Doping Code (Code), WADA is responsible for the preparation and publication of the List. It is an International Standard identifying substances and methods prohibited in-competition, out-of-competition and in particular sports. For a link to the list, click on the WADA logo.

Substances and methods are classified by categories (e.g., steroids, stimulants, gene doping) and the list is updated every year and it is valid for a calendar year. The agreed process for the annual consideration of the List includes three meetings (see timeline below) of WADA’s List Expert Group with a draft discussion List being published and circulated for consultation in June, following the second meeting.*
At its third meeting in September, the List Expert Group, following consideration of the submissions received from the consultation process, recommends the new List to the Health, Medical and Research Committee which in turn makes recommendations to WADA’s Executive Committee. The Executive Committee finalizes the List at its September meeting.
The use of any prohibited substance by an athlete for medical reasons is still possible by virtue of a Therapeutic Use Exemption (TUE).

Few interesting modifications are:

1) To reflect the growing number of substances developed to stimulate erythropoeisis, hypoxia-inducible factor (HIF)-stabilizers have been added as an example.

2) Intra-muscular use of Platelet-Derived Preparations (PRP) has been removed from the Prohibited List.

3) Desmopressin has been added as an example of masking agent.

4) Methods that consist of sequentially withdrawing, manipulating and reinfusing whole blood into the circulation have been added to this category.

5) Methylhexaneamine has been transferred to the list of specified stimulants (it seems to be a popular choice these days…)

6) At the request of the Union Internationale de Pentathlon Moderne (UIPM) and due to changes introduced in the format of the competition, alcohol is no longer prohibited in Modern Pentathlon for disciplines involving shooting.

7) It is clarified that, in addition to Bobsleigh, beta-blockers are also prohibited in Skeleton, which are both governed by the Fédération Internationale de Bobsleigh et de Tobogganing (FIBT).

8) At the request of the Fédération Internationale de Gymnastique (FIG), gymnastics has been removed from this category.