Abstract DiSupLo (Diffusion Supported Loading) is acronym defining the method of loading of APIs into the pores of mesoporous silica particles (MSP). In this approach the starting material, homogenized physical mixture of two or more components (APIs/MSP) is placed in the closed vessel containing the ethanol. In the first stage of the process, there is no direct contact between solid mixture and liquid solvent, the only one is between the diffusing vapors of ethanol and solid matter. In the second stage, the vapors penetrate the solid state mixture in the whole volume, locally condense and dissolve the API. On this stage API dissolved in the minimal volume of solvent is transported to the pores of MSP. The applicability of method is proved employing selected APIs - Ibuprofen, Flurbiprofen, Ketoprofen, their mixtures and MCM-41 as MSP drug carrier. DiSupLo is quantitative process with high filling factor reaching value much higher compared to classical “wet methods”. Advances Solid State NMR techniques with sample spinning 60 kHz (1H Very Fast MAS, 2D 1H–1H RFDR MAS, 2D 1H–13C invHETCOR), 1H–13C HSQC High Resolution (HR) MAS as well adsorption-desorption, PXRD, DSC and FTIR were employed for analysis of loading and interactions of API's inside the pores.