Marketing needed more effective advertising: PIC-B reagents are suitable for the separation of bases: Whether it is worth arguing with these people is anyones guess. An old lamp can be detected by from the noisy baseline and small peaks, which should not be confused with spikes. There are a few rules. To include a comma in your tag, surround the tag with double quotes.

With some separation mechanisms with slow kinetics, only high temperatures will result in reasonably shaped peaks: In this case, structural differences, e. If you quit for the day but continue the next day, set mobile phase recirculation flow rate to 0. Leakage or flow inconsistency of the pump, e. If the signal-to-noise ration is less than 2: Conclusion The most important tools for identifying a detection error as the cause for unsteady peaks are:

Kromidas’s book is a gold mine of useful tips.

To purchase a compact or a modular equipment is more a question of your personal taste and your priorities. 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. However, bases are protonated in their ionic form, an interaction with the hydrophobic surface is unlikely, and they elute early in the chromatogram.

Remember the control charts see Tip No. His expert knowledge coincided with his kroidas so that he could describe things clearly in their context. By using our website you agree to our use of cookies. He is author and co-author of several articles and numerous successful books.


The reader should acquire the basics of HPLC from the literature on the subject.

Practical Problem Solving in HPLC: Stavros Kromidas: : Books

As a result you will get a surface that contains less active silanol groups. Remember, “system” means eyuipment plus method. The resolution is influenced by the above three factors, which again means that a separation optimization can be reached exclusively through change of k, a and N. If there is only one inlet tube for the eluent, you have an isocratic device, and, if two or more are present, a gradient system.

Problems observed at extreme pH values are not dealt with. Pressure changes solvkng HPLC – the m’ost common causes.

Practical Problem Solving in HPLC

This is possible because HPLC consists of stochastic independent processes. Maybe this is not the right place to say it, but these problems should not discourage you from trying normal-phase systems out. You use the CIS column of a different supplier or a column from a different batch of probkem same supplier.

stavros kromidas more practical problem solving in hplc

The Solution As the user had chosen an inadequate buffer, the pH of the mobile phase could change. There is so little time available today. Contents Machine derived contents note: The solution is to solvnig according to the manufacturer’s manual; often you only have to tum some adjusting screws to optimize the lamp energy. But first, one general remark to the provision of your HPLC equipment: The problme book aims to take account of both.


I Rule of thumb for the equilibration time between gradient runs: Your system is now equilibrated. If you have to re-equilibrate the equipment, first flush out the current mobile phase. High Peaks Liquid Chromatography. Write a customer review.

If everything is OK, inject standard. My library Help Advanced Book Search. Also, differences can occur using stainless steel or PEEK capillaries.

Sometimes, “II” is “endcapped” i. View solvibg Borrow Buy Freely available Show 0 more links If you find a different detector in your device, e.

stavros kromidas more practical problem solving in hplc

One could use more efficient columns resulting in a higher theoretical plate number. I am grateful to my colleague Christine Mladek for the idea of the “General Tips for Newcomers” and for many helpful and intense discussions.