1. Simulation of Radio Frequency Quadrupole Mass Analyzer Stephen Jones EPS 109 Final Project 11/27/12

2. Radio Frequency Mass Analyzer Used in Mass Spectrometry to separate ions with specific mass/charge (m/z) ratio Design:  Four electrodes with positive and negative DC voltage on diagonally opposite rods  RF AC voltage applied 180° out of phase between pairs of diagonal rods Acceleration= (charge)x(E field) /(mass) Skoog, D.; Holler, F.; Crouch, S. Principles of Instrumental Analysis 6 th Ed.; Brooks/Cole; Belmont, CA 2007.

3. Radio Frequency Mass Analyzer - continued Both DC and AC potentials are increased during run to obtain m/z spectrum Full scan on the order of milliseconds Skoog, D.; Holler, F.; Crouch, S. Principles of Instrumental Analysis 6 th Ed.; Brooks/Cole; Belmont, CA 2007.

4. Stable vs. Unstable Trajectories Stability is determined by  Dimensions of RFMA (r 0 )  Mass (m)  Charge (e)  DC Voltage (U)  AC Voltage (V)  AC Frequency ( ω rf ) Stability can be determined with parameters a and q Stable Unstable F. Muntean, Int. J. Mass. Spec. Ion Proc., 151 (1995) 197-206

5. Simulation Parameters  Field radius = 3.5 cm  Mass 1: 722.66 Dalton  Mass 2: 57.81 Dalton  U = ± 20 Volts  V = ± 400 Volts Molecule 1 (blue) is inside region of stability (a = 0.04, q = 0.4) Molecule 2 (red) is outside region of stability (a = 0.5, q = 0.25) 1,2,3-Tritetradecanoylglycerol http://www.chemfinder.com/chembiofinder/Forms/Search/ContentArea/ChemBioV izSearch.aspx?FormGroupId=8&AppName=CHEMBIOFINDER&AllowFullSearch =true&KeepRecordCountSynchronized=false&CurrentIndex=1 Similar to: Isopropylamine http://www.chemfinder.com/chembiofinder/Forms/Search/ContentArea/ChemBioV izSearch.aspx?FormGroupId=8&AppName=CHEMBIOFINDER&AllowFullSearch =true&KeepRecordCountSynchronized=false&CurrentIndex=5

6. How to Run Run with script: SMJ_EPS109_finalproj.m Function: quad.m