HPLC problems

Table 3.12 HPLC Problems, Probable Causes, and Remedies3...

The HPLC user should know or learn what to look for and what to do to prevent HPLC problems and, finally, what can and should be done before calling a service technician. User s manuals, manufacturer s advice, books, articles in scientific journals, computer programs, and network sites can be used as resources for troubleshooting. A general rule is that one can know that a problem exists only when one knows how the system operates when it is working well. This means that keeping detailed records of system performance (log book) is very helpful. 

In HPLC instrumentation troubleshooting, problems can be classified as follows. Major HPLC problems are discussed under this paragraph, while an extended summary of problem causes and remedy actions are tabulated in the respective tables. 

A clogged column frit is another common HPLC problem. To minimize this problem from the start, the... 

A number of papers have been published on the HPLC analysis of alkaloids in order to study the possibilities for such analyses in general. The papers comprise a wide variety of alkaloids and HPLC systems for their separation. The data published in these papers may be useful in connection with many separation and other HPLC problems in the analysis of alkaloids. Therefore some of the data of general interest are summarized in the present chapter. However, in other chapters of this book, HPLC systems that may be useful for alkaloid analysis in general, have also been dealt with (see Table 2.1). 

Common HPLC problems are caused by component malfunctions (pump, degasser, injector, detector, data system, column), and faulty preparation of the mobile phase or sample preparation. Problems can be categorized into several areas ... 

Table 10.4. Summary of Symptoms of Common HPLC Problems and Probable Causes...

Table 10.4 summarizes the symptoms of common HPLC problems and the most probable causes. Developing HPLC troubleshooting skills often takes many years of operating experience and a working understanding of the principles of the instrument as well as considerable patience to eliminate all the typical causative factors. 

The next step would be to search for rules which conclude "there is no solvent flow". The process would continue until the conclusion "the pump is broken" is either proved or disproved. In this example, the chemist would be asked to input information whenever an IF clause was an observable symptom of an HPLC problem. 

Although the adsorption and normal-phase modes are not often used by many chromatographers, both have great potential for solving HPLC problems. Although mostly used with non-polar solvents with a polar modifier, polar-bonded-phase HPLC columns can also be used with organic/water combinations for additional unique selectivities. 

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