Beginning with the calculation of capacity factors for isocratic HPLC separations, over the modelling of complex gradient elutions with up to 10 steps, up to the simultaneous calculation of the influence of 7 experimental parameters, it was a long but successful journey.

DryLab^® allows systematic and continuous establishment of chromatographic selectivity by measuring and modelling eluent properties, such as gradient time tG, %organic eluent (B), pH of the aqueous eluent (A), ternary eluent composition, additive concentration (Buffer, ion-pairing), etc. Columns can be compared based on their resolution maps.

 

Selectivity changes can be followed visually in the chromatograms.

After generating the maps of critical resolution, the user can avoid more than 95% of those experiments, which are not the best ones. This is a strong increase in efficiency and performance in the method development laboratory, resulting in time saving for more important activities.

New developments in an overview:

1. Extension of DryLabs capabilities to 3-Dimensional Optimization: We are able to model 3 Dimensional Design Spaces, based on 12 experiments (the Cube). The Cube can show >1,000,000 virtual chromatograms with high precision and can show the interaction of tG, T and ternary composition or tG-T-pH, or other combinations. The Robustness Space is presented in a virtual mode and allow to establish Robust HPLC Methods and visualize them much faster than in the past.

2.The link between PeakMatch^® and DryLab^® has been improved. Relevant experimental data are collected automatically over night and and are transfered to PeakMatch to start the peak tracking process for the method. Systematically (by DoE) generated chromatograms and the DryLab^®-input data are now in one single file and allow the user the visual demonstration of best working conditions (such as step-gradients, etc.) and critical robustness regions.

3.Two new functions have been integrated into the automation-interface, to allow

a. The easy import of simulated chromatograms in the AIA/AnDI-Format and

b. The export of the critical Resolution Map

4. The DryLab^® Toolkit is able to receive column temperature values for the optimization, even if the temperature is not the modelled variable. Measured peak widths are now available also for isocratic models.

Our goal is a systematic and automated generation and collection of data of all runs which describe the history of an HPLC method and link such data more closely to a DryLab^® model. Our tG-T models with 4 experiments are representing ca. 10,000 virtual chromatograms and you can see the best one in seconds.

Additional new developments are summarized below.

5. The presentation of data from six experimental chromatograms (for DryLab^®
experimental design elution strength (tG) vs. pH; (tG) vs. ionic strength; (tG) vs. additive
concentration and (tG) vs. ternary solvent composition has been improved
showing six chromatograms with peak tables on one page.

6. A column database for the comparison of stationary-phase selectivities of more than 470 columns has been integrated into PeakMatch^®.

7. The method robustness of a separation can be calculated from 4 individual DryLab^® models

8.. Robustness calculations for step gradients are now available.

9. Automated generation and collection of basic runs, renaming and data transfer into PeakMatch is now available for several popular data systems, including LCsolution^® (Shimadzu), Chromeleon^® (Dionex) and ChemStation^® (Agilent).

10. Two dimensional models: DryLab^® strongly supports the Design Space concept which becomes more and more important also for analytical and method development work. The simultaneous optimization of two parameters is now possible for any combination of elution strength (gradient time or %B) with following parameters:

a. Temperature

b. pH

c. Ternary eluent composition

d. Additive concentration,

e. Ionic strength

11. Three dimensional models: To further support the Design Space concept, simultaneous optimization of three parameters showing the biggest influence on method selectivity is now possible.

Molnár-Institute exhibited the new developments at the “HPLC 2009” in Dresden as a Silver Sponsor. The institute gave a well-visited vendor seminar and a lecture in the “Quality by Design” session and presented the new versions for the evaluation of the Design Space in the exhibition part of the meeting. Also the institute exhibited at the Pittsburgh Conference 2009 and 2010 and at the Eastern Analytical Symposium 2009 (EAS) and at the Analytica 2010 in Munich, Germany.