1. Transferring LC-UV to LC-MS.
Things to think about.

2. .
All methods have 3 parts

3. Some questions to ask before transferring a method
Some questions to ask before transferring a method. So that we know when were’ done!
What is the structure? Will MS see it (Science).
What is the point -Quantification or Qualitative?
What is the dynamic range needed?
What are the method requirements to be considered good?
What type of changes can be made (Politics)?
What type of data do you expect to get (History)?

4. Modes of chromatography Where are we?
This visual image captures most of the common modes of liquid chromatography. A majority of chromatography done is reversed phase.

5. How Can We Affect Chromatographic Resolution intentionally or by accident? System Hardware differences-What all are we changing?
Efficiency
Selectivity
Retentivity
Chromatographic resolutions focuses on 3 parameters Efficiency Selectivity and retentivity . They are highlighted here in the resolution equation
Focusing on one parameter at a time whether it is efficiency, selectivity or retentivity will only get you so far it terms of separation performance. For example it is easy to increase the efficiency of your separation by going from a 50 mm column to a 100 mm column and the improvement will be a square root function. However it is seen that this approach will only go so far and the improvement becomes proportionally less as the column length increases. Also pressure increases, which limits the separation potential even further.
So all factors must be examined
Initial
Increase N
Increase k
Increase  5 5 5

6. Chemical Factors That Affect Selectivity Changes here can be the biggest issue
Column
Chemistries
Organic
Solvent
Creating Selectivity α
Elution solvent
Stationary phases
Particles
Surface chemistry
Mobile phase pH
If we look at the parameters that influence selectivity, you can look at the points of the selectivity triangle.
Organic solvent, the column chemistry and the mobile phase pH, gradient slope and temperature all play a role
Mobile Phase pH
Gradient Slope
Temperature

7. So about MP A Non volatile vs volatile buffers This is typically where the fun starts. Mobile Phase modifiers it is really about the column and compound structure

8. UV & PDA Detector Detection mechanism
Analyte must have UV chromophore, with double bonds–C=C-, -C=CH-CH=C-
A chromophore absorbs the light at a specific wavelength, lmax.
Solvent may change throughout separation - gradient
Not very temperature sensitive
Not flow sensitive
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9. Mass Spectrometers (MS)
Detection Mechanism
Measures the mass-to-charge ratio (m/z)
Compounds must have a charge (+ or -) associated with them to be detected.
The compound can acquire a charge, e.g. acid contributing H+ (protonation).
MS detection occurs in a high vacuum environment .
In LC/MS analytes must go from a liquid to a gaseous environment.
Mobile phase must be volatile so it can be removed.
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