CORTECS C18+ Columns are packed with superficially porous particles that are modified to include a low-level positive surface charge. This modification mitigates the secondary interactions between basic probes and the stationary phase. This interaction has been known to cause poor peak shapes and poor sample loading especially at low pH with silica based stationary phases. The work shown here illustrates the improvement in peak shape that can be obtained when using CORTECS C18+ Columns versus a non-modified superficially porous particle C18 column. In the case of the reversed-phase QC reference material, the CORTECS C18+ Column yielded a peak capacity 10% higher than the other column tested, due entirely to the peak shape improvements seen for the basic analytes. This improvement was achieved simply by switching the column, without any method development or need to change mobile phases.