LC Reference Library

This section contains everything you wanted to know about Liquid Chromatography products!

Method Development

General

• HPLC Chromatogram Library - Searchable by compound and CAS number
• Online Application Notes
• Separation Criteria and Goals
• Column Selectivity - A Powerful Tool When Developing Reversed-Phase HPLC Separations
• What is the effect on an LC separation of changing the particle size and column length? 
• What is the effect on an LC analysis of changing the column diameter? 
• What is the effect on the LC separation of changing the pore size? 
• What temperature should I use for my separation? 

Column Selection

General

• Choosing the Right HPLC Column
• Choosing a Column for High pH Reversed-Phase HPLC Separations
• How to Order Custom Columns
• HPLC Column Descriptions
• USP Listing for LC Columns
• Do you have an equivalent column for my LC column? 
• I can’t get enough retention of my basic compounds at low pH, what column should I try next?
• I’m trying to separate some very difficult basic compounds at pH 2.5 using a C18 column and their tailing factors are still too high — around 2.0. Which column should I try next?

Specific

• What column do you recommend to analyze raw materials?
• What is the difference between the StableBond SB-C8 and Rx-C8 columns? The SB-C18 and Rx-C18 columns?
• How do I buy columns from additional lots to do my method validation testing? 
• I'm having a problem with resolution and selectivity for a phenyl column using different lots, how can I resolve this problem?

Guard Columns

• Guard Columns and In-Line Filters
• How do I select a guard column for an LC analysis?
• Which guard columns and guard hardware do I use for ZORBAX standard cartridge columns and all Agilent cartridge columns? 

LC/MS

• Choose the Bonded Phases Best-Suited for Your LC/MS Separation

• Very short narrow-bore columns seem ideal for LC/MS. What bonded phase should I use?

High Throughput

• I typically select 4.6 x 250 mm, 5 µm columns for my analytical work because I have complex samples, but I need to reduce my analysis time and increase my sample throughput. What can I do?
• My work requires very high sample throughput. How fast can I do a gradient separation? 

Troubleshooting

Instrument

• What solvents can be used on my liquid chromatograph? 
• How do I prevent bubbles from getting into the flow cell?  How do I remove bubbles from the flow cell? 
• How to Find and Fix Common Leaks
• How to Properly Install Sample Loops
• How to Select the Right Rotor Seal
• What are the differences between partial and complete loading? Which sample loop should be used?
• Troubleshooting Guide for HPLC Injection Problems
• Burst Pressure of PEEK tubing

 Retention, Efficiency and Peak Shape

• What can cause a loss in column efficiency (theoretical plates)? 
• How do you evaluate for column voids?
• The peaks on my chromatogram are tailing. How can I improve their shapes? 
• What causes peak tailing in reversed-phase HPLC and what can I do about it? 
• How do I prevent peak tailing and splitting?

Baseline Noise and Drift

• How can I reduce the baseline noise? 
• What causes baseline spiking? 
• What causes baseline wander? 
• How do I stop my baseline from drifting? 
• There are ghost peaks in the chromatogram. How do I eliminate them? 
• What can cause ''mystery peaks'' in my LC analysis?
• What solvents do you recommend to clean the columns? I use THF

Laboratory Practices   

• Determining the Dwell Volume of Your System
• Buffer Selection 
• Buffer Preparation
• Filtration of Contamination

General Consumable Information

• Agilent 1100 Connectors

• Agilent LC Test Screw Top Vials

• LC Fitting Types

• LC Tubing