In situ investigation of scCO 2 assisted impregnation of drug into polymer by high pressure FTIR micro - spectroscopy

Supporting information a Adjustments performed to optimize the infrared spectra: 1) The cell was centered under the beam 2) The opening of the diaphragm was adapted to the sample to meet two requirements: it had to be not too large to avoid the detection of surrounding CO 2 but not too narrow to obtain a sufficient signal to noise ratio. A preliminary study was performed for each geometry and size of sample to determine the best size of the diaphragm opening. 3) The focusing of the beam was adjusted by changing the vertical position (z axe in Figure 1) of the cell. Depending on how the focusing was performed, we found that the baseline changed (increased either in the near infrared region or in the far infrared region) and that Electronic Supplementary Material (ESI) for Analyst.