I am using VECTASHIELD® HardSet™ Mounting Medium with DAPI (Cat No. H-1500). The sections look good initially, however I do see bubble or vacuole formation occur under the coverslip after some time. Do you have any suggestions on how this situation can be remedied?
Fixed, thin cut (<10 um), glass mounted sections are recommended to be used in combination with this medium. Unfixed material, thicker sections or the use of gasket or chamber slides or well formats may increase the incidence of bubble formation when applying H-1500. If using thin sections as described, ensure an adequate volume of the medium is being applied to spread out under the coverslip. Storage of slides in the freezer (-20 °C) may also reduce the incidence of bubbles. For existing mounted sections with bubble formation, coverslips can be removed by soaking the slides in buffer, and then remounted using fresh media.