An ordinary silica or TYPE-C™ silica guard column could be used to trap impurities from your samples if that is what you are trying to do. Sometimes different phase columns are used to do 2D LC separations.
However, we typically do not recommend using different phases together (for guard and analytical) because of the changes to the separation that different phases can cause.
If you are only concerned about particulate matter, I would recommend pre-column, Cogent Column Filters since they do not normally adsorb samples and only filter out non dissolved particles. For this application this would be the best choice. Otherwise the guard column of the same phase is really the only guard column that could be recommended without possible undesirable changes to the separation.
