Calibration Mixtures

In order to get comparable lipophilicity, protein and phospholipid binding data we need to calibrate the retention times in each HPLC system using a calibration mixture.


Valko test mix C-18

10 mM DMSO solutions of 10 components with logP ranging from -0.5 to 5.5. A chromatogram is  supplied using C-18 stationary phase with column dimensions of 3 x 50 mm, and flow rate 1.5 ml/min, applying fast ACN gradient.


​Valko test mix IAM.PC.DD2

The calibration mix ensures that the CHI IAM values are consistent and reproducible using different instruments, columns. It is advisable to calibrate the retention times and use the actual slope and intercept of the plot every day to calculate the CHI IAM value of drug discovery compounds. Always use the given CHI IAM values on the table for the calibration. Remember: CHI IAM values above 50 indicate phospholipidotic potential, a large volume of distribution, and a long half-life. CHI IAM values can be used to estimate the volume of distribution and drug efficiency together with the HSA binding data.

Calibration mixtures can be ordered from REGIS Technologies together with the IAM.PC.DD2 column, or from this site.


HSA and AGP calibration solutions

Use these drug compound solutions in 10mM DMSO to form a calibration plot for HSA and AGP binding.  The tables show the percentage bound of each compound and the corresponding log retention time and log K obtained from HPLC experiments.


​System suitability test solutions for IAM.PC.DD2 chomatography

The calibration line is used to standardize the gradient retention times on a given column. To check that the IAM.PC.DD2 column represents the true phospholipid binding we need to check the CHI IAM values of a few neutral, acidic and basic drugs. IAM.PC.DD2 columns can last over 5000 injections, but the suitability should be tested after every 200 to 400 injections. The test solutions are also available to order online or send the "Contact us" form to order.

The obtained CHI IAM values for the drug molecules should be within 5 unit of the value listed in the table on the right.