Class Notes (887,096)
CA (530,907)
UVic (2,823)
CHEM (163)
CHEM 212 (12)
Lecture 7

CHEM 212 Lecture 7: Sept. 21/2016

3 Pages

Course Code
CHEM 212
Hamilton M.Coreen

This preview shows page 1. Sign up to view the full 3 pages of the document.

Loved by over 2.2 million students

Over 90% improved by at least one letter grade.

Leah — University of Toronto

OneClass has been such a huge help in my studies at UofT especially since I am a transfer student. OneClass is the study buddy I never had before and definitely gives me the extra push to get from a B to an A!

Leah — University of Toronto
Saarim — University of Michigan

Balancing social life With academics can be difficult, that is why I'm so glad that OneClass is out there where I can find the top notes for all of my classes. Now I can be the all-star student I want to be.

Saarim — University of Michigan
Jenna — University of Wisconsin

As a college student living on a college budget, I love how easy it is to earn gift cards just by submitting my notes.

Jenna — University of Wisconsin
Anne — University of California

OneClass has allowed me to catch up with my most difficult course! #lifesaver

Anne — University of California
Chem 212 Lecture 7 Sept. 21/2016 Approaches to Quantification: 1. External Standard 2. Internal Standard 3. Standard Addition External Standard: -Calibration standards -Calibration curves (plot of signal versus concentration) -Use calibration curve to "Read" many unknown samples -avoid single point calibration for deterring Sa =kna or Sa=k[A] -Single point assumes linear relationship over large concentration range => Not good -potential error by assuming calibration curve goes through zero -error in reported concentration is difference in x-axis=>accuracy problem -can not solve this by replicates=>systematic error -Multipoint external standard method: -requires cal curve -hopefully y=mx+b or a non-linear equation -use least squares on spreadsheet -never assume linearity beyond calibration points: -dont assume anything past 1st and last calibration points because you don't know if linearity continues forever -sample signal must be in range if too high then dilute it -Calibration standards must "bracket" unknown concentration -if its not then fix it adding more sample or diluting sample -May need "Matrix Matched" standards or use "method of standard additions" -matrix may have some kind of interference -instead of making standard in reagent water I would also have some other materials to mimic the blood -Internal standard does nothing for matrix interference -if complex matrix you probably won't want to use external standard curve Internal Standard Quantification: -Add a known amount of internal standard to the unknown sample -a related compound that is not the analyte is added to the sample before you do anything else -Signal from analyute is compared to signal from internal standard to determine amount of analyte in sample -Isotope dilution is the ideal way but not only way -Measure Calcium with magnesium as IS -Pick something that has same chemical and physical properties for internal standard I.S. Analyte (75%) 100ng 75ng -measure by ratio compared to standard -if we spill sample the ratio is s
More Less
Unlock Document
Subscribers Only

Only page 1 are available for preview. Some parts have been intentionally blurred.

Unlock Document
Subscribers Only
You're Reading a Preview

Unlock to view full version

Unlock Document
Subscribers Only

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.