As a core pharmacology laboratory for Center for AIDS Research at UCSF, the Drug Research Unit (DRU) often encounters problems regarding column selection during memthod development. Here I propose to seek for funding to buy 25-50 analytical columns as a column kit for method development.

Background (Rationale): Drug quantification requires optimal separation to achieve high selectivity and specificity. Different drugs may require different columns to achieve optimal separation and quantification. For a new method development, we generally choose a column used for existing assays at DRU, or based on similar methods from literature, which we often find are not the best choice, as most laboratories like ours may only have a limited number of analytical columns tested for method development. Here I proposed to purchase a set of columns covering different separation mechanism and column dimension. A general summary of different columns is listed as follows:

1. Reverse phase columns: C₂, C₄, C₈, and C₁₈ columns.
2. Normal phase and HILIC columns: un-derivatized silica-, amide-, diol-, cyanopropyl-, aminopropyl-, zwitterionic sulfoalkylbetaine-based columns.
3. Hypercarb column: based on carbon graphite, retention mechanism is different from reverse phase columns and HILIC columns, and show good retention time for polar compounds.
4. Ion exchange columns.
5. Monolithic columns: Chromolith™ SpeedROD RP-18e.

Analytical columns have different particle size (1.8, 2.7, 3, and 5 μm). Particularly sub-2 μm columns are used for the UPLC system recently acquired by DRU through a RAP CTSI-SOS shared instrument award. Fused-core columns having particle size of 2.7 μm are suitable for the LC system coupled with the API5000. Columns with 3 and 5 μm particles can be used in all LC systems in DRU.

Analytical columns have different dimensions (2.1x50, 2,1x100, 2,1x150, 3x150, 4.6x50, 4.6x150). I proposed to acquire two dimensions for each type of column: 2.1x50 mm and 2.1x150 mm.

Plan of use: The DRU does not have the resource to buy a full range of different columns. If we can get fund to buy a column kit, it will benefit DRU and our collaborators at UCSF greatly. This column kit is only used for the purpose of column selection during early stage of method development. Only drugs in clean solvent will be applied to those columns. Once a column was identified for a new assay, the same column will be purchased for the later stage of assay development. Therefore, the column kit can be repeatedly used for any new assay development. The newly acquired UPLC system is open to co-investigators and others at UCSF on Monday and Friday. They can also use the column kits to develop methods. This is especially useful for them because analytical columns in non-analytical labs are very limited. It is not worth buying a new column if only a small number of samples are analyzed.

Budget: each column costs $400-700, average $550, we seek for $25,000 to secure a variety of columns for method development.

Collaborators: Collaborators (B. Joseph Guglielmo, Sunil Parikh, Katherine Yang, and Janel Long-boyle) and investigators who will use our core facilities.