High performance liquid chromatography i.e HPLC analysis is a sophisticated method and require a good system. The HPLC parts consist of few parts. Some of them can be classified under most essential and others moderately essential. Essential ones require to be made of better quality and technology. Any problems in these parts can completely hinder the HPLC process while other moderately essential ones can be substituted easily and will not be so detrimental for the system to work.
HPLC Pump the first of the HPLC parts:
This is the hplc part which pumps the mobile phase at constant pressure and flow rate through the column. Mostly piston types also called constant displacement pumps are widely used. They have limitations of pressure i.e one can rise the pressure of the pump only to certain limit. After that exceeds pump gets automatically stopped. More than one pump is fixed to th HPLC system based on the type of flow requirement. For gradient type you use mostly dual pump and if you are using only isocratic type, then single pump will do.
Video shows an automated HPLC system which loads the sample on its own and give you final results on the monitor. The more the automation, the less is the time consumed and also the chances for errors.
HPLC Injector: This is the part of HPLC used to load the sample into the system. This is done by two injections, one is external syringe which load sample into HPLC injector. This injector loads the sample into the stream of mobile phase. For more refer the article on HPLC injection.
HPLC column: This is the mandatory HPLC part on which actual separation of compounds occur. The HPLC columns have fixed lengths, diameter and also the particle size of the stationary phase to choose based on our requirement. The longer columns are used for separation of complex mixture with many components. While shorter columns are used to separate less complex mixtures. Most columns we use are of reverse phased columns made of C8 or C18 type o f non-polar stationary phase. The columns also have a specific direction for the hplc mobile phase to flow. This is indicated by an arrow on the column.
HPLC detector:
This is the critical part of HPLC. Sample separated has to be identified with the detector. If there is a problem, the entire effort goes waste. The detector mostly used are UV, Electrochemical detector, Photo-diode array detector, florescent detector etc.
Computer operated software: HPLC system is always connected to a computer having related HPLC software. This software regulates the pump, detector, sample injection etc depending on the model you purchase or the configuration you have chosen while buying it. The more the software control, the better as handling and human errors are minimized.
Guard column: This is used as a safe guard to the main column. This prevents any particulate matter from directly enterin into the column and there by choking it.
Reservoir: This is the bottle having mobile phase in it. If isocratic only one is sufficient, If gradient type, more than one reservoir is used.
Syringe; This is specially designed syringee unlike locally available ones. The volume of sample njected is mostly in a few micro litres. So syringe with accurate rulings are used for the purpose. Ex: Hamilton syringe.
