Details of short-term constancy The area is proportional to the injected amount. What is the linear range of the new fluorescence detector? In order to test whether the whole equipment is functioning, inject a standard mixture, which is normally specified in the operating procedure. Degassing is possible with helium or the built-in degasser see Tip No. The method and not you will be the problem in the future. How do you rate the supplier’s innovation?

Conclusion The examples above are designed to make you pay attention to chromatographic details, to explore what and why things can go wrong. Test by switching off the pump; its noise contribution is easily measurable. Silica gel dissolves more readily at smaller particle size. In each case the problem, the solution and the conclusions are presented over a maximum of 4 pages, and in addition the book contains manufacturers’ addresses, references, data tables and checklists. Kromidas’s book is a gold mine of useful tips.

stavros kromidas more practical problem solving in hplc

They will stick onto rough, “dirty” surfaces. Another rule of thumb: Alternatively, the capacity of a pseudo-stationary phase could be saturated see Tip No. The stqvros of the stationary material does not matter – you could even use ! The Solution Very simple: Subjects High performance liquid chromatography. If necessary, use column-switching valves to facilitate selectivity tests with different columns.

In general, there should be more use for SPC statistical process control in the laboratory. He has worked in the area of HPLC since and has given lectures and training courses since The remarkable thing about the new technique was the high kromidae to avoid confusion we should speak about high column pressure that gave the name for this technique.


More Practical Problem Solving in HPLC

SPC is a simple universal useful moe for monitoring data, enabling early recognition of errors and failures and observing trends. Broad and tailing peaks can be observed; sometimes “ghost peaks” are detected. The first has a peak width of 0.

This way, manufacturing-induced impurities are flushed out of the column as well as other dirt. Now to our subject.

Practical Problem Solving in HPLC

Flushing of HPLC equipment. At an actual separation also the “chemistry” naturally is important, because the kinetics of the adsorption desorption, for example, depends on the surface of the stationary phase and the temperature. This will simplify method transfer. That is the retention time in the mobile phase 1mplus the retention time in the stationary phase I’R At otherwise constant conditions see belowpossibility of comparing the behavior of substances in similar or in different systems, e.

Practical Problem Solving in HPLC: Stavros Kromidas: : Books

Subsequently, we zoomed in on the baseline 3. Is it directly coupled to the main column or via an intermediate piece? In Lieu of an Introduction.

stavros kromidas more practical problem solving in hplc

It can happen that, at your current temperature, a peak is hiding underneath another peak. This practice-oriented book does not fall short of explaining the reasons underlying the problem, and what is just as important, it voices caveat from the consequences of the mistakes one can commit in trying to gain soving over the instrument and the separation process. The Solution Syavros shows the dependence of retention time on methanol content in the mobile phase for the separation of organic acids and bases with an reversed phase.


Before suspecting the column as the cause of a bad resolution, you should rule out the dead volume.

With the current number of suppliers and types of equipment, this kkromidas be a major problem, even for an experienced user. If the dead time till is constant and the retention times increases, this means that the pump is OK and the cause is temperature, column or mobile phase. The Case Noisy or drifting baselines and pressure fluctuations are signs of insufficient degassing.

Runge, who recognized the adsorption characteristics of lime and paper and The slope represents the enthalpy differences and the y intersection the entropy values. Published Weinheim ; [Great Britain]: At 6 s the third component can only be seen as tailing, and at 24 s the resolution between the first bplc the second peak is unacceptable. Often you have to decide on your priorities in terms of selectivity, detection limits and robustness.

The history of chromatography is probably well known, as well as various anecdotes about the subject.