Blood sugar test strips?

[gary350]

There are people that can not pay $74 including sales tax for blood sugar test strips.

Does anyone know how the test strips work?

I wonder if am ohm meter will test blood resistance with a very small gap of a certain distance between the test leads?

The strips appear to be an electric printed circuit board type strip with a very small gap about .010" on the end.

Before I try to build something for my digital meter I was hoping someone would have information how this works?

**broken link removed**

 

[kubeek]

I would guess the strips are coated with some special chemical that reacts with the glucose and enables measurement.

 

[jpanhalt]

This looks like a reasonably modern explanation: http://www.diabetesforecast.org/201...st-strip.html?referrer=http://www.google.com/

This excerpt for the FDA form 510(k) application for your device (required for sale in the US)(http://www.accessdata.fda.gov/cdrh_docs/reviews/K092602.pdf ):

A method based on glucose oxidase is often used as a comparison standard. In both methods, an enzyme is used to oxidize glucose in the blood. The enzymes are quite substrate specific. In the current home-use methods, the electrons lost from glucose are detected as an electric current mediated by FAD as the cofactor. In the glucose oxidase method, hydrogen peroxide is produced which reacts with a dye to produce a color.

Finally, appropriate strips are available for less, assuming you bought a box of 100 strips: http://www.amazon.com/FreeStyle-Lite-Glucose-Test-Strips/dp/B003GQZ9E2

I do not think you could duplicate the strips at home. Moreover, any physician treating you would be a fool to rely on data you produced from home-made strips.

John

 

[KeepItSimpleStupid]

I know resistance varies as a function of time, so therefore Coulombs makes sense. There is a large "ground" are on my strips which is probably part od the auto turn-on. The advertisement says it does double testing, Not sure what that means.

Plenty of info when you search for "glucose meter application note"

• There is a laser based device in the works: https://www.news-medical.net/news/2...-transform-lives-of-people-with-diabetes.aspx I saw a better explanation somewhere.

Google has a contact lens based system.

Some of the insulin pump manufactures have a continuous glucose monitoring system that monitors fluid beneath the skin. It needs calibration after every insert. Your not supposed to rely on it without confirmation. There is wireless communication to the glucose meter, the sensor and the pump so it can render alerts.

It would be nice to have a device that works like a pulse oximiter.

The device I use needs no coding anymore. They figured out how to make the strips use the default coding.

Fortunately my strips have zero cost. Most of the meter manufacturers will replace glucose monitor for free. If you can attend an event sponsored by a glucose manufacturer, they will likely give the meters away free.

Mom uses the drum based meter. Because of severe arthritis inserting small strips would be difficult.

I have the ability to "Tag" readings. Unfortunately, you can't ignore them. Sometimes if you don;t was your hands you can get an abnormally high reading. Reukts from multiple meters can be read into a PC.

I have about 6 meters for one strip and 1 for another. Mom has two meters plus a spare and one for anpother type of strip. I used to flip between two and mom flips between two. We both have the same "other" strip.

Both of us had to briefly change (her - almost) because the insurance would not cover the meter. In her case, they don't have the lancets that are integral to her meter. (detachable).

I love the Multiclix (now Fastclix) 6 lancet drum device. The needle is so small that it doesn't even leave a mark on my fingertips.

So, at most, you only have to buy one meter. Getting another as a spare for free requires some sweet talking or going to a seminar.

You either need two meters or glucose control solutions.

 

[gary350]

I am not trying to duplicate test strips. I was going to build something like a needle point .010" resistance gap then take a ohm meter reading across the gap with blood on the gap. I should be able to compare known blood glucose readings to the ohm meter reading of the resistance gap then draw a glucose resistance graph. Above says, current magnitude is proportional to glucose level. It seem logical this will work. Not very simple for the average person to do at home but if a pre made resistance gap with meter is already setup anyone can use it.

 

[jpanhalt]

And how would your results vary with your state of hydration?

John

 

[KeepItSimpleStupid]

There's that glucose sensitive chemical on the strips. I think arsenic is used as a preservative. I did, for curiosity sake, did measure the strip resistance and it varies with time.

 

[ChrisP58]

I am not trying to duplicate test strips. I was going to build something like a needle point .010" resistance gap then take a ohm meter reading across the gap with blood on the gap. I should be able to compare known blood glucose readings to the ohm meter reading of the resistance gap then draw a glucose resistance graph. Above says, current magnitude is proportional to glucose level. It seem logical this will work. Not very simple for the average person to do at home but if a pre made resistance gap with meter is already setup anyone can use it.

That presumes that the resistance of the blood sample varies predictably with the glucose level, and not by any other factor.

The literature on glucose testing all refer to a chemical or enzyme that reacts to the glucose level. And it is the electrical characteristics of that reaction that the meter measures. And, I'm going to guess that that reaction is a one time process. So you'll need a new quantity of that material for the next test. Also, I'm sure that the exact amount of that material needs to be tightly controlled for accurate and consistent results.

 

[jpanhalt]

It is based on coulometry, which is not simple resistance.

John

 

[jpanhalt]

gary350

Please clarify whether the diabetic is yourself or whether this "invention" is for someone else?

John

 

[AnalogKid]

The way I read it, the meter is more a volt or amp meter than an ohm meter. The blood sample and the strip form a little teeny battery.

ak

 

[KeepItSimpleStupid]

The way I read it, the meter is more a volt or amp meter than an ohm meter. The blood sample and the strip form a little teeny battery.

ak

More like a coulomb meter. Something that is measured with an electrometer. When I worked, I had access to one. I also measured small currents (pA) by dividing by time. It's the integral of current.

 

[kubeek]

Above says, current magnitude is proportional to glucose level. It seem logical this will work.

Incorrect, above says that the amount of liberated electrons when using that enzyme is proportional to the glucose level. Nothing about current magnitude or even resistance in there.