Presentation on theme: "Advanced Systems, Inc. Chromatography Integration and Trouble-shooting Presented by: Marlene Moore October 2007."— Presentation transcript:
Advanced Systems, Inc. Chromatography Integration and Trouble-shooting Presented by: Marlene Moore October 2007
Advanced Systems, Inc. Agenda Problems Tools Solutions
Advanced Systems, Inc. Problems Baseline Disturbances Irregular Peak Shapes, Sizes Retention Time Shifts Loss of Separation or Resolution Quantitation Difficulties Rapid Column Deterioration Ghost Peaks Broad Solvent Front
Advanced Systems, Inc. Baseline Disturbances spikingnoisewander drift offset
Advanced Systems, Inc. Spiking Particulate Matter Passing Through Detector Loose Connections Cables Circuit boards
Advanced Systems, Inc. Noise Contaminated Injector/column Physical Defect Detector Defective Detector Board Carrier Gas Leak at Septum or Column FID, NPD, FPD Column in Flame Incorrect Combustion Gases or Flow Rate/leak ECD, TCD Air Leak
Advanced Systems, Inc. Wander Contaminated Carrier Gas Isothermal Conditions Contaminated Gas Chromatograph Poor Control of Carrier Gas or Detector Gas Flows Poor Thermal Control of Detector
Advanced Systems, Inc. Drift Septum Bleed Upward GC or column contamination Damaged stationary phase Downward Incomplete conditioning of column Unequilibrated detector
Advanced Systems, Inc. Offset Contamination: Injector, column, detector Carrier gas - change/install impurity traps Column Inserted Into Flame (FID, NPD, FPD) Malfunctioning or Improperly Set Recording Device
Advanced Systems, Inc.
Peak Shape Peak Shape tells the story of your chromatography
Advanced Systems, Inc. Irregular Peak Shapes tailingfrontingsplit roundednegativereduced
Advanced Systems, Inc. No Peaks Plugged Syringe Broken Column Injecting Sample Into Wrong Injector Column Installed in Wrong Detector Integrator Reading Wrong Signal or Not Connected Detector Not on Temperature Oven not heated Column temperature too low Injection port temperature too low Detector Gases Improperly Set or Not on Very Low or No Carrier Gas Flow
Advanced Systems, Inc. Reduced Peaks Plugged Syringe Change in Injection Technique Large Leak - Injector Split Ratio Too High Too Short of Purge Activation Time for Splitless Injections Very High Septum Purge Flow Too Low Injector Temperature Column Temperature Too Low Sample Components Absorbed by Column or Inlet Liner
Advanced Systems, Inc. Reduced Peaks Initial Temperature Column Too High for Splitless or On-column Injections High Background Signal - Contamination Excessive column bleed Check auto zero function and setting Improperly Operated Detectors Impurities Carrier Gas or Detector Gas Detector Compound Mismatch Excessive Attenuated Integrator Signal Sample Concentration or Integrity Problems
Advanced Systems, Inc. Tailing Peaks Active Injector Liner or Column Contaminated Injector liner Column Dead Volume Caused by Poorly Installed Liner, Column or Union Poorly Cut Column End Polarity Mismatch - Stationary Phase, Solute or Solvent Cold Spot in the Flow Path
Advanced Systems, Inc. Tailing Peaks Solid Debris in Liner or Column Poor Injection Technique - Too Slow Too Low of a Split Ratio Overloading on a PLOT Column Decrease sample amount Amines and carboxylic acids tail on most columns Need ph modified stationary phase Some Peaks Always Exhibit Tailing
Advanced Systems, Inc. Rounded or Flat Topped Peaks Overloaded Detector Exceeding Range of Integrator
Advanced Systems, Inc. Split Peaks Detector Overloaded Poor Injection Technique Poorly Installed Column Into Injector Column Temperature Fluctuations Coelution of Two or More Compounds Mixed Sample Solvent for Splitless or On-column Injections.
Advanced Systems, Inc. Negative Peaks All Peaks Negative - Polarity Check Connectors TCD - Select Peaks Thermal conductivity of compound greater than carrier gas ECD - After Positive Peak Dirty or old ECD cell
Advanced Systems, Inc. Retention Time Shifts Different Column Temperature Different Carrier Gas Flow or Linear Velocity Leak in Injector - Septum Contaminated Column Change in Sample Solvent
Advanced Systems, Inc. Loss of Separation/Resolution Contaminated Column Damaged Stationary Phase Different Column Temperature, Carrier Flow Rate, Column Large Changes in Sample Concentrations Improper Injector Operation
Advanced Systems, Inc. Quantitation Difficulties Injection Techniques Split Discrimination Different Purge Activation Time for Splitless Injection Baseline Disturbances Improper Integrator Settings Inconsistent Detector Gas Flows or Temperatures Column or Liner Activity
Advanced Systems, Inc. Rapid Column Deterioration Exposure of Column to Air at Elevated Temperatures Exceeding Upper Temperature Limit of Column Chemical Damage Contamination of Column With High Molecular Weight Materials Column Breakage
Advanced Systems, Inc. Ghost Peaks Contamination Injector Column Septum Bleed Dirty Syringe Sample Too Large Previous Run Terminated Too Soon BOO!
Advanced Systems, Inc. Broad Solvent Front Poorly Installed Column Leak in the Injector Solvent Interacting with Detector Too Low Split Ratio (Flow) Injector Temperature Too Long Purge Activation for Splitless Injections Large Injection Volume Low Column Temperature and High Boiling Solvent High Column Temperature and Low Boiling Solvent
Advanced Systems, Inc. NO! WRONG ANSWER!!! Solutions Quickest Solution ---- Improve Chromatography --- Do Manual Integration --- Get Results out Fast !!
Advanced Systems, Inc. Solutions Preventive Maintenance Clean detector Clean injector Clean and repair parts Clean and tighten connections Follow instrument manual suggestions Allow Time for Optimizing System Integration parameters Programs
Advanced Systems, Inc. Does anyone have a question? Question ! Where do you document your trouble shooting?