Lactate biosensor could become…

… a simple test for CFS?

Credit: American Chemical Society. 

Saw this interesting article today. Since lactic acid and lactate is the prime substances that makes muscle feel exhausted and sour, may be this technique could become and easy way to test for CSF.

First human tests of new biosensor that warns when athletes are about to 'hit the wall'

Wednesday, 24 July 2013

A new biosensor, applied to the human skin like a temporary tattoo, can alert marathoners, competitive bikers and other "extreme" athletes that they're about to "bonk," or "hit the wall," scientists are reporting. The study, in ACS' journal Analytical Chemistry, describes the first human tests of the sensor, which also could help soldiers and others who engage in intense exercise — and their trainers — monitor stamina and fitness.

Joseph Wang and colleagues explain that the sensor monitors lactate, a form of lactic acid released in sweat. Lactate forms when the muscles need more energy than the body can supply from the "aerobic" respiration that suffices during mild exercise. The body shifts to "anaerobic" metabolism, producing lactic acid and lactate. That helps for a while, but lactate builds up in the body, causing extreme fatigue and the infamous "bonking out," where an athlete just cannot continue. Current methods of measuring lactate are cumbersome, require blood samples or do not give instant results. Wang's team sought to develop a better approach.

They describe the first human tests of a lactate sensor applied to the skin like a temporary tattoo that stays on and flexes with body movements. Tests on 10 human volunteers showed that the sensor accurately measured lactate levels in sweat during exercise.

"Such skin-worn metabolite biosensors could lead to useful insights into physical performance and overall physiological status, hence offering considerable promise for diverse sport, military, and biomedical applications," say the scientists.

Future research will further correlate sweat lactate levels with fitness, performance and blood lactate levels, Wang added.

Reference:

Electrochemical Tattoo Biosensors for Real-Time Noninvasive Lactate Monitoring in Human Perspiration

Wenzhao Jia, Amay J. Bandodkar, Gabriela Valdés-Ramírez, Joshua R. Windmiller, Zhanjun Yang, Julian Ramírez, Garrett Chan, and Joseph Wang 

Anal. Chem., 2013, 85 (14), pp 6553–6560, DOI: 10.1021/ac401573r

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ZenMaster

Again…

…I have not been writing for a long time. Some time ago, my father died after a short illness. He was 84, so I guess it was not completely unexpected, still difficult. However, around Christmas, I noticed that I anyhow had managed all that had happened around his illness, death and funeral surprisingly well – physically speaking. This betterment has continued now during January too, so maybe the extra weakness and pain from the hormone imbalances and pituitary surgery last spring finally is going away.

I also now know that the MR brain scan in September showed a ‘clean’ pituitary! They didn’t see any residual tumour tissue on those pictures. Of course, in the end, there could be some few cells left, that slowly will continue to grow again, but for now everything looks fine.

In the autumn, I was also referred to a new specialist, specialising in neuro-muscular diseases and genetic mitochondrial conditions that now are known from DNA sequencing investigations. I spent almost two hours going through my whole story, from 25 years ago until now, with him. Well, really my whole life story –medically speaking. He even asked about if I had noticed something already as a kid and when growing up. The result of this interview/discussion with him was that he was going to take some time and think about my condition and story, and if he could figure out something, he would come back. This was in early October.

Well, now last week, I got an appointment for taking muscle biopsies. Exactly what he is going to check I don’t know, and I really don’t expect anything new to come out of this. But of course, it is good that someone is testing something new about CFS. Maybe there is something wrong with the energy producers in the muscle fibres – the mitochondria’s.

I will have another, completely different test done too. My father died of a ruptured aortic aneurysm, and when I told my cardiologist about this at the yearly ultrasound check-up of my heart, he immediately referred me to the vessel specialists here at the hospital. The condition is much more common in male siblings of known patients, and furthermore they started general screenings of all men at 65 years here in Uppsala some two years ago. So the knowledge is present here. I only hope it has nothing to do with my known brain aneurysm, or the hiatal hernia I have had for a long time now. It could be a generalized weakening of smooth muscle cells in these structures, but it could also be specialised disruptions at each site causing the different bulginess. No one knows the exact reason for aneurysms or hernias.

ZenMaster