Help - turning mg/dl glucose into uM for ascorbate

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Help - turning mg/dl glucose into uM for ascorbate

Post Number:#1  Post by ofonorow » Wed Nov 08, 2017 6:32 am

To all brilliant forum members. I am looking for help and suggestions in converting weird units (of our Bioavailablity work) to the standard uM concentrations in the Sen, et. al. CSC paper.

I may have posed this question before, but I want a topic devoted to converting our BioAvailability experiment numbers, which are mg/dl - as if the meter was reading glucose, into the equivalent micromoles/L.

My biochemist friend couldn't come up with a formula, but suggested we measure known concentrations of vitamin C with the meter.

Ergo 1.5 mg/dl is 85 uM/L according to the tables.

We create a 1.5 mg/dl of vitamin C, using sodium ascorbate to keep the pH neutral and simulating blood, and determine the FreeStyle Lite glucose reading.

We can to this all the way up from say 3 mg/dl known concentration, to 2.0 mg/dl or higher. At that point we could create the conversion formula from the numbers in our study to the actual vitamin C uM/L.

Thoughts?
Owen R. Fonorow, Orthomolecular Naturopath
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#2  Post by ofonorow » Fri Nov 10, 2017 11:25 am

Trouble in river city.

i am creating a deciliter solution of sodium ascorbate. I heated and added salt. Then I started by adding 0.1 mg of sodium ascorbate. (On advice from a bio chemist that pH can play a role). The new True Metrix meter was about double the Free Style Lite 2, e.g. 410 mg/dl versus 221 mg/dl, so even if it can read ascorbate, the values won't correspond to our previous work.

But the measurements are "all over the place" so I started dipping my finger in the solution and taking the measurement as if I was taking my own blood. (I made two solutions, but the first worked but the second seemed to always error. No idea why)


Code: Select all

Concentration                FreeStyle Lite Meter 1                 FreeStyle Lite Meter 2
0.1 mg/dl                      200                                             221
                                     273                                            313

0.11 mg/dl                    25                                              254
                                    402                                            355
 
0.12 mg/dl                    Hi                                               Hi

0.30 mg/dl                    Hi                                               Hi


Put a new battery in the unit that is reading higher than the other. Lots of errors (wasted test strips)

I think the only thing to do is try adding ascorbic acid, and see if the measurements come out more standardized. Thoughts?
Owen R. Fonorow, Orthomolecular Naturopath
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#3  Post by ofonorow » Fri Nov 10, 2017 11:36 am

Found one mistake! It is a gram scale so 0.1 gram is 100 mg (not 1 mg).. Big sigh of relief

Need to do increments of 0.01 (10 mg).. or better yet, 0.001 g (1 mg)

Can ball park that 200-300 on graph below is around 100 mg/dl which is around 5700 uM/L

So the highest that can be reached orally, or 177 on the Freestile Lite is 177/250 of 100, or .71 x 100 or approximately 71 mg/dl, meaning our test subject got up to around 4031 uM/L from oral admin of ascorbic acid at minute 14.


Image
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#4  Post by Johnwen » Sat Nov 11, 2017 1:09 am

First I believe you need to understand better the units your dealing with.
Here's a wiki to explain it a little better.

https://en.wikipedia.org/wiki/Molar_concentration

Now each substance carries it's own molar weight so you must be specific, for V-C here's a calculator.
you can enter the amounts in the blank space and it converts them all to their amounts.
Don't forget to subtract the amount of sodium you put in the mix. Different animal! :wink:

http://unitslab.com/node/223

Hope this helps.
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#5  Post by ofonorow » Sat Nov 11, 2017 5:39 am

It does, but here is what I am trying to do. The meter is reading vitamin C - but thinks it is reading glucose in the blood. So the numbers, while proportional, are meaningless.

For example, when the glucose meter in the Bioavailability study read 177 mg/dl - we want to know what the real vitamin C concentration was in mg/dl? My biochemist friend told me the only way to convert is to measure known concentrations of vitamin C in a test solution, and then develop the formula that converts from our numbers to the actual concentrations of AA in mg/dl. (After we have the actual AA in mg/dl, it is easy to use the tools like you provided to convert to the now standard uM/L). Ouila - we will have a better idea of what blood concentrations can be achieved orally, which is much higher than is generally accepted at the moment.

The mistake I made yesterday - measuring 100 times more vitamin C than I intended, and the associated "Hi" readings, have renewed my enthusiasm. I have a .001 gram scale, and today I will go through the normal blood range .1 mg/dl to 2.0 mg/dl (if I can get that precise). Otherwise 1 mg/dl, 2 mg/dl, 3 mg/dl, etc. looking for a linear relationship.

Finally, there is a new editor at the Journal of Orthomolecular Medicine (JOM). We had submitted the Bioavailability Paper last spring, but the change in management caused the ball to be dropped. I was just told that our BIO paper will be published in the next edition of JOM.
Owen R. Fonorow, Orthomolecular Naturopath
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#6  Post by pamojja » Sat Nov 11, 2017 6:28 am

ofonorow wrote:For example, when the glucose meter in the Bioavailability study read 177 mg/dl - we want to know what the real vitamin C concentration was in mg/dl? My biochemist friend told me the only way to convert is to measure known concentrations of vitamin C in a test solution, and then develop the formula that converts from our numbers to the actual concentrations of AA in mg/dl. (After we have the actual AA in mg/dl, it is easy to use the tools like you provided to convert to the now standard uM/L). Ouila - we will have a better idea of what blood concentrations can be achieved orally, which is much higher than is generally accepted at the moment.


Why you simply don't get serum ascorbate levels tested themselves? Where I live I've paid EUR 25,43 for a single AA serum test.

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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#7  Post by Johnwen » Sat Nov 11, 2017 11:30 am

I agree with pamojja on getting a blood test.
Now here’s the trick!
Make sure you have a pen and paper handy!
Take your test meter and equipment with you!
Talk to the lab tech that draws your blood and tell them you want to check your glucose meter with the draw blood levels when you get your results.

What you do is when you sit down for the draw, prep your meter and when they do their draw have them pull the needle after their draw and the blood that comes out after the removal is what you test. Then they can wipe and bandage the draw spot.
Then when this is over do a finger stick and compare this number with the draw blood spot number and find the ratio between the two.

The blood from the draw is veinal blood when you stick your finger it’s capillary blood. So at this point you have a differential ratio between these two bloods.
Now when you get your test results you can compare the results from your draw blood and see where your meter’s accuracy is and figure this difference into your equation.
Then convert the labs number with the ratio’s and you’ll have a base line number to work your tests with.
You’ll also be able to come up with a serum level change’s using the ratios and differences from the test.


https://www.walkinlab.com/vitamincbloodtest.html
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#8  Post by pamojja » Sat Nov 11, 2017 11:56 am

Johnwen wrote:https://www.walkinlab.com/vitamincbloodtest.html

Refrain from taking vitamin C supplements or fruits 24 hours prior to sample collection.


Just don't follow this advise, because then you wouldn't know where you're daily dose takes you. The lab has to know what they do, otherwise the half-life of ascorbic acid fully applies.

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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#9  Post by ofonorow » Sat Nov 11, 2017 2:50 pm

Yes, it occurred to me to take some of my own blood - and add vitamin C to it for these glucose meter calibrations, (The answer why I just don't use a lab to do all the measurements is because you'd have to take a blood draw every minute for the first fifteen minutes!)

New Mystery... Help johnwen! Doing the calibrations and both meters (initially) lined up very nicely, but the glucose meter readings for sodium ascorbate were consistently about 100 points higher than the ascorbic acid readings :?: :?: :?:

I had planned to measure and add vitamin C to one deciliter. My brilliant biochemist friend suggested starting with say 100 mg/dl, but then diluting the solution. A lot easier!

So I created the "blood" by heating water, adding 90 mg/dl sugar, 9 mg/dl salt. I made 6 dL.

I then used the FreeStyle Lite Meters to baseline :?: (test strip lot 1501413 2016/07)

Code: Select all

Meter 1                        Meter 2
59                                Lo


I was hoping for close to 90.

Then I created two vials of 100 mL (1 Dl) simulated blood and added 110 mg sodium ascorbate and 100 mg ascorbic acid to the other

Code: Select all

Concentration      Sodium Ascorbate                            Ascorbic Acid
                       meter 1     meter 2                         meter 1    meter2
100 mg/DL      345            346                                180           175


So the numbers jived, but are way different between sodium ascorbate in the water, and ascorbic acid in the water??? Why is that??

Here are the rest of the readings today..

I added 11.11 of the blood to dilute to 90 mg/dL - and that seemed to be the formula for the rest, even though the volume was getting large, just add 11.11 mL of "blood".. need to double check this

Code: Select all

Concentration      Sodium Ascorbate                            Ascorbic Acid
                       meter 1     meter 2                         meter 1    meter2
100 mg/DL      345            346                                180           175

 90 mg/DL      363            300                                 129           192

 80 mg/DL      218            192                                 180            89

 70   mg/DL    292            219                                 125          141

60   mg/DL     214            146                                 163           156

50  mg/DL      291            130                                  131          162


A big source of error is in taking the measurements. I found that dipping my finger in the solution, and then taking the measurment off my skin produces the least ERRs, but I wish there was a better way to test the sample consistently.

And all ears why such a difference on the same meters between SA in solution and AA in the same solution.

At least this blood-simulation, with glucose, should help us match the actual numbers in the Bioavailabilitystudy
Owen R. Fonorow, Orthomolecular Naturopath
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#10  Post by Johnwen » Sat Nov 11, 2017 11:37 pm

Ok let’s get down and dirty on what your doing with these solutions your testing.
First lets look at something’s that at first might not look to be related but as we go on you will see how this all comes together.

V-c lowers the ph of water making it more acidic. Lets look at what lowering the ph does to electrical conductivity.

you see that strongly acidic [or strongly basic] solution will have high conductivity Since the pH is a measure of the concentration of the Hydrogen [and the Hydroxyl] ions, for an acidic solution, the lower the pH [i.e. the higher the H+ concentration,] the greater the conductivity will be. Remember, the conductivity is the sum of the contribution of ALL the ions present in the solution.


https://www.researchgate.net/post/Relat ... ductivity2


So V-c lowers the ph and conducts electric better. CHECK!

Next Salt (sodium) water is a better conductor of electricity then regular water?
Common ions in water that conduct electrical current include sodium, chloride, calcium, and magnesium. Because dissolved salts and other inorganic chemicals conduct electrical current, conductivity increases as salinity increases.


http://www.fondriest.com/reviews/scienc ... nductivity

So Yes! The more salt in the solution the higher the amount of conductivity it posses.

So Far we have learned that by varying the ph such as adding ascorbic acid to water increases conductivity! Now add sodium to this mix and we have even a better conducting fluid!
At this point your probably wondering what this has to do with your testing?
Answer; A LOT!!!
Now were going to learn how these home monitors work by watching some you tubes. Turn up the sound!

https://www.youtube.com/watch?v=Evw5AqUYJcg

Next one 11:13 min.
This one is next in line on you tube you can let it load by itself or click on the link!

https://www.youtube.com/watch?v=l1MeyIG0JPs




So here’s a recap of what’s going on!

On the test strips there is a enzyme that converts the glucose in the blood to
Ferricyanide which levels vary by the amounts of glucose then this is electrified and the conductivity across the solution is measured and reported as glucose levels.
By using solutions that do not contain glucose do not get converted and what you are measuring is the electrical conductivity of solution that reaches the test chamber part of the test strip. The reactions of the solutions with the enzymes and the ferricyanide in the mix chamber also react differently depending on the differences in ph, salinity and other mineral contents of the solution.
So yes your readings will be all over the place especially if there is a difference in the type of meters used and the method of testing in the strips.
Remember these meters are designed to test blood and trying to sidestep their design are not going to give you good results!

At least this blood-simulation, with glucose, should help us match the actual numbers in the Bioavailability study


But you still have find a conversion between plasma levels and whole blood levels to come up with a bioavailability levels.
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#11  Post by ofonorow » Sun Nov 12, 2017 12:38 am

Thank you Johnson. Explains why biochemist friend suggested sodium ascorbate -- to keep pH more like that of the blood.

the late Jay Patrick founder of Alacer Corp/EmergenC, wrote that when AA is taken the body attaches a sodium, so that all vitamin C is sodium ascorbate. Biochemist Sherry Lewin seemed to disagree, saying vitamin C expelled from the cell in the Lymph was sodium ascorbate.

The problem, other than the IV/C, the primary measurements are of high dose AA. It is possible I suppose that the concentrations of AA are even higher than we thought, if the meter reports low for AA.

I may have to run experiments like you suggest.

I am also thinking about using the standard glucose testing solutions used to test and calibrate glucose meters (since my own blood would coaggulate)

Johnson, what us your formula to create simulated blood?

I used distilled water. Maybe I should start with saline?

90 mg/dO glucose seemed correct, but I should check my starting blood sugar in the bio experiments.

What else should I check to make these calibrations apples vs apples?



The objective is to understand what the AA readings of my own blood are showing.
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#12  Post by ofonorow » Thu Nov 16, 2017 5:08 am

Bump. Still need to calibrate the glucose meter to help us understand what the numbers taken from the blood really mean, especially after a large ascorbic acid intake.

Good news is that the meter is DEFINITELY responsive to the concentration of vitamin C. The relationship appears linear. The problem is that the magnitude of sodium ascorbate and ascorbic acid, the meter readings, are so different. We need to simulate what ascorbic acid would measure in the blood stream, e.g. quick arterial measurements.

One question is whether I should start with saline - rather than distilled water?

The other idea after speaking with my biochemist friend is to try and keep the pH in the two simulated blood solutions roughly equivalent to blood pH, and that might mean buffering. One obvious buffer is sodium bicarb (baking soda). Other thoughts/ideas welcome.
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#13  Post by ofonorow » Thu Nov 16, 2017 4:06 pm

Experiment 2 - also has me baffled...

Started with sterile saline - heated to about 100 degree farenheit.

Added around 110 mg of sugar - realized that sucrose is 1/2 glucose and 1/2 fructose. should be using dextrose. (Explains the low sugar readings last time). This time, in saline, I could not get a baseline reading on the meter.

Checked the initial ph of the saline - 7.2

Added the 100 mg of aa to the 100 MG (DL) and the pH was 6.9
Then added 111 mg of sa to the 100 MG (DL) and the pH was 7.1

So I attempted to "buffer" the solutions with baking powder to achieve the 7.35 target pH. However, the more I added, the lower the pH went (the more acidic !?!).
+25 mg baking powder - pH 6.7
+100 mg baking powder - ph 6.5
+300 mg baking powder - 6.4

? I need a better/stronger buffer...

Then I noticed that the "aluminum free baking powder" is not only sodium bicarbonate, it contains MonoCalcium Phosphate, Sodium Bicarbonate, and Corn Starch.

Then the readings were Hi on the meter, for the 100 mg/dL concentration, so perhaps starting with saline will interfere with the measurements?

changes for next time.

Try 1//4 saline, rest distilled water.
Use dextrose, rather than sucrose
Find pure sodium bicarbonate or some other pH buffer
Owen R. Fonorow, Orthomolecular Naturopath
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#14  Post by ofonorow » Fri Nov 17, 2017 12:00 pm

Looking for help why the saline based simulated blood always read "Hi" on the glucose meter.

According to google,

Sodium concentration in the blood is 310-334 mg/DL

Sodium content in Saline is 900 mg/DL (but they say the osmality is similar to blood?)

Assuming this is correct, perhaps I should dilute the saline by 1/3?
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Re: Help - turning mg/dl glucose into uM for ascorbate

Post Number:#15  Post by Ascorbic » Sat Nov 18, 2017 12:57 pm

Here is my reading of PMID: 23885992.

"To estimate the blood ascorbate concentrations from the FSBG readings, the FSBG readings of each sample point were subtracted by the baseline glucose readings of the relative subject: AAFSBG = FSBGX − FSBG0 (AAFSBG is the estimated blood ascorbate concentration, FSBGX is the FSBG reading at a given time point, FSBG0 is the FSBG reading before IV infusion of ascorbate)."

Thus, AAFSBG = FSBGX − FSBG0

The above formula is reasonable because you want to "zero" out the initial glucose reading.
The initial reading represents the measured starting glucose level, any change in the reading of the glucose meter should reflect a change in
ascorbate levels not glucose.

From the last post of the previous thread on this topic:
FSBG(15)= 177
FSBG(0) = 128

Therefore, AAFSBG(15) = FSBG(15) - FSBG(0)
= 177 - 128
= 49 mg/dL ascorbate

From http://www.endmemo.com/medical/unitconv ... amin_C.php ,

49 mg/dL= 2.782 mM

[Note that 49 is just below 50 which the article thought was the minimum
ascorbate level needed for an accurate reading.]

The article went on to use a correction method that did seem to help though did not
result in statistically improved estimates. Correcting by dividing AAFSBG by 0.90
might still be a good idea.

The finding that oral dosing can possibly lead to ascorbate levels of 2.8 mM or perhaps
even higher is an important result. It would be very helpful if a blood test could be
done that might confirm this important discovery.


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