Analytics for Chemistry, Biology and Production:

Analytics for Chemistry, Biology and Production:
A Hammer for a Wrist-watch. It's easy to repair with adequate Tools _{P. Forster}


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Can you do that?: I don't believe — except you . . . (but see later!):
Linearity: — maybe a little more ?

Have you ever seen such nice and validated Linearities "by" Beer-Lambert? — I see it routinely, almost every day, and I have more then enough time to drink my coffees.

As you have just seen before,^[1] checking the Linearity and the usable measuring range is one of the most important primary basic-tasks for every good, modern spectroscopist, independent if he is interested in only single wavelength measurements or in good, reliable chemometrics.^[2]
If we count together what's all required:

your Reference Substance(s) -
it needs a little more in case of Chemometrics.

your buffered Solvent(s)

at least 7 - 10 unique Dilution ratios

preparing, measuring the spectra, calculation of the Linearity.

validate the found Linearity.

finish Documents of the Linearity with your personal Sign.

- then I hear almost every "not so modern spectroscopist" cray: "You are crazy, probably you're a missioner - or so. Nobody can spend so much time solvent and whatever, only to check the Linearity !!!" And now you hear all his "good" experiences taken during so many years. Did he tell you, how many times he repeated several of his worked-out calibrations? And how many times he .... . And ..... !
Let's stop - we have better things to do!

Let's have a look at the Linearity report:

Linearity report of Hexamine-Cobalt-Trichloride
(

: "Double-click" on the images to enlarge)

Frontpage:

With your "self-created" Frontpage, nobody else is able to bet your Linearity report, except ... .

Measurement Page: The First Raw Result page of your report!

On the top: The real measurement protocol
On the bottom: The calculation of the Linearity: -
with statistics and!!! visualisation.

Why are you so surprised about the exact taken Dilutions?
Why are you so surprised about this Linearity?
Is it not nice — fantastic!
[I'm almost daily amazed about "soooo" high precision in nature (General Beer Lambert Law!)]

Do you know, why you can't see the the "trumpet" of the standard deviation?
Do you know, why your eye is a much better indicator as the "precise" S._yx ?

Raw Result Page: The Second Raw Result page of your report!

On the top: The real raw results of the Linearity - the spectra!
On the bottom: The list of sample data for the taken raw results.

It's probably the first time you see such plots for Linearity — but:
This plots are absolutely required to "document!"
the Linearity "by" Beer Lambert!
Have you analysed the plots and the statistics on both raw result pages?
What can you tell me about your inspection?
(Remember the time stamps, especially the difference between any two spectra! We need it a few moments later!!)

The Validation Page:
It's real validation according to Beer Lambert Law!

On the top: The normalized raw results, as it is required for Linearity!
On the bottom: The list of sample data for used raw results:
The same as on second raw result page!.

It's probably the first time you see such plots — but:
This plots are absolutely required to "document!"
the Linearity "by" Beer Lambert!
I'm sure you know, why you cannot divide all the spectra in the plot, - but why you see some ?higher? noise instead.
(Remember the time stamps, especially the difference between any two spectra! We need it a few moments later!!)

Are you able to do similar? ......! Why? ......! Very suasive!!

The related SST Page:^[3] Only to be very excellent and complete!

Including this particular page into your report, it's the daily taken SST, nobody can argue against your measurements/results in any way, any more, without starting a very big battle against NIST/FDA/USP/EP/etc.^[4]

And best of all:

This page costs you every day only 10 - 15 seconds (+ printout time)!

Your personal Sign on the Measurement and the SST page closes your complete Linearity Report:
It doesn't need either, anything more, nor anything less!!

Measurement "Screen":

Are you interested to see how many inputs were required to measure and calculate the Linearity and generate the plots?

You can do it with even less inputs, if you use predefined Dilution-Rows!

If you like you can "order" "broken" dilutions like: 1 in 3.768 or 1 in 19.321 or 1 in 35.16 or 1 in ... .

Have you realized, I used twenty dilutions not ten! NO, 20 Dilutions - not 20 measurements!
Tell me: Why have I ordered my preferred dilutions in this oddish sequence?
And how about automatic dilutions!
( In the new Version of the Software you can do things also with the mouse! )

There are several advantages to measure the Linearity of substances this way.
I will only remember on at this moment, because I have realised, that most of you have a exorbitant interest in MOLAR ABSORBTIVITY, also known as: molar absorption coefficient, molar extinction coefficient, molar absorbtivity, etc.:

As you may see, using this method to determine the Linearity, results in an absolutely easy game to calculate the molar absorbtivity for any wavelength you prefer, not only the one we selected in our Linearity report.
There is a recipe: "How to determine/calculate molar absorptivity coefficients?", where, in case you have done till here, only Step 7.) and 8.) is left to You !!
You may also realize, that no one else before (except my little 'I') has it done with this excellent precision, specially if you include the corrected size of your used cuvette into calculations.
I'm sure you know why you are able to guarantee absolutely for the linearity and the calculated molar absorbtivity coefficient with such a precision and for any wavelength You prefer!

Time and Solvent requirements:
Now it's the moment to calculate the required amount of time and the required amount of solvent for our Linearity Report.
Let's go through our method description:

Task	Time required	Solvent required	Remarks
Prepare 1 Litre buffered Solvent	10 min	(1000 ml)
Balance the sample for the stock solution	5 min
Prepare 250 ml stock solution	10 min	250 ml
Enter all required Inputs	1 min
Prepare & measure the Base line	1 min	15 ml
Prepare & measure 10 selected Dilutions: 10 * 1.4 min // 10 * 12 ml	14 min^*)	120 ml
Calculate & printout 1. Raw result page	1 min
Prepare & printout 2. Raw result page	2 min
Prepare & printout your pre-designed Frontpage	2 min
Sign your report & stitch it together	1 min		Don't forget the copy of the SST!
Enjoy your required Coffee-/Tea-break	15 min	(250 ml)	Of course: NOT solvent!
Total^[5]	47 min !!!!	385 ml !!!!	Is there something wrong??

^*) Is it "congruent" with your time calculation you did above ??
Why are you looking like "Thomas the unbeliever" ?
Are you STILL doing it the way as already the honoured Gentlemen Mr. A. Beer and Mr. J. H. Lambert did it ?
What for a drawback! — After More then 250 years! and that - by YOU ?

Did you know ?:

That you are able to measure and document more then 2300 Linearities per year without any overtime ?
That you don't have to wash all the "Million" of graduated Glassware during a year ?
That you don't have to pay any of this cheap, graduated glassware during a year, anymore ?
That you can sell the largest part of all your graduated glassware right now ?
That you almost never will have to repeat the same Linearity determination again ?
That you can reuse your Linearities during the next 20 years, or more, if your system survives ?
That you can export your Linearities very easy to other, similar spectro systems (with a small calculation) ?
Have we already reported about the solvent you save during the year and what it means to your spectroscopy costs ?
That you can have exact the same benefits measuring spectra or concentrations or kettle charges or ... or ... ?
That you can have exact the same benefits determining mixing ratios or other quality lab tasks ?
That you can have exact the same benefits determining pharmaceutical quality tasks, like CU or DR ?^[6] ?
And by all you are doing you have, for absolutely no extra charge, automatically SMV and SRI^[7] ?
That you have to drink more then 2300 Coffees per year, without loosing any working minute ?
That 2300 Coffees per year is equal 10 Coffees per Workingday (= 2.50 Litres/day) ?
(Of course: If you drink a little less Coffees, you can do 15 Dilution raws a Workingday, with ease!!)
That it is allowed for you to drink Tea instead of Coffee ?
How long will the resulting pay back time be, for such a spectro system, doing not only reliable Linearities and molar absorbtivity coefficients ?

What's the magic behind ?: Nothing — Absolutely nothing !
(Remember: "'Repair' your watch with the adequate tools!")

The only thing you have to do is to take absolutely care for only four things!:

First:	and the most important: "Celebrate" a correct spectroscopy according to the full Beer Lambert Law !
Second:	Use the adequate, reliable spectrometer for all your measurements !
Third:	Use a adequate and real "Dynamic Dilutor" !^[8] Attention: At the moment, there are only two models on earth !
Fourth:	Use a reliable Software, which is able to drive all devices and takes care as much as possible to "celebrate" a good spectroscopy according to the General Beer Lambert Law ! Yes, a typical expert system ! (Of course, you may do all the calculations by hand, and the entire documentation too, — if you prefer so! But then I hope for you, that you can at least record all the spectra in a "quasi digital mode" ! In this case, take care, for not recording the spectra too fast, — it's for your more reliable results !^[9])

^References:

[1]	"Spectroscopy: Lesson 2: 8. That's real linearity and how you have to test it !" [Paragraph 5.), case a.)] www.p-forster.com/english/themes/spectroscopy
[2]	"Chemometrics: Forget it once and for all, this papers talking about .... and reports at the same time only an absolutely minor precision and reproducibility ! www.p-forster.com/english/themes/Chemometrics
[3]	SST: The System Suitability Test of the spectrometer and system. www.p-forster.com/english/themes/Suitability
[4]	NIST: National Institut of Standards and Technology. www.nist.gov FDA: Food and Drug Administration US. www.fda.gov USP: US Pharmacopeia. www.usp.org EP: European Pharmacopoeia. www.pheur.org
[5]	What have I told: 7. A good, modern spectroscopist will do it in a little more then a hour ! [Paragraph 5.), case a.)] www.p-forster.com/english/themes/spectroscopy
[6]	CU: Content Uniformity - including Active Substance Identifikation on all 10 or 30 Dosage Units. DR: Dissolution Ratio - the Dosage Unit Desintegration Test (Dissolution Test). www.p-forster.com/english/products/ARGUS/T_PAGES/T_PAGE_S.html
[7]	SMV: Sample Method Validation. www.p-forster.com/english/themes/spectroscopy SRI: Sample Reference Identification. www.p-forster.com/english/themes/spectroscopy
[8]	I'm sorry: But nobody is able to change a "static" Dilutor into a "dynamic" Dilutor by any way ! Also is nobody able to create a "dynamic" Dilutor, too, if he is using two Dispensers ! www.p-forster.com/english/themes/DynamicDilutors/DynamicDilutors.htm
[9]	Remember: There is absolutely no possibility to have both, high speed and high reliability at the same time, — specially not on a scanning spectrometer ! www.p-forster.com/english/themes/spectroscopy But you can do it simultaneous, with ease and without any Disadvantage: www.p-forster.com/english/themes/spectroscopy/Spectroscopy_FAQ.htm#FAQ_SM01

Peter Forster:

Software Development & Consulting
Peter Forster
Neubadstrasse 88
CH-4054 Basle, Switzerland

Mail to: peter.forster@p-forster.com

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