Jan 06,2023

　　The empty capsule can be filled with various oils or liquid medicines or suspensions that have no dissolving effect on gelatin, and can also be filled with solid medicines. The suspension of the filled solid drug in the empty capsule is also relatively common, and the drug powder in it passes through at least 80 mesh sieves. The dispersion medium or PEG400 of the suspension should also be added with a suspending agent. The suspending agent added to the oily base is a 2-10% paraffin mixture, and 1-15% PEG6000 is often used for the non-oily base. Constant stirring is required during the pilling process, which improves the accuracy of the loading and keeps the content uniformity within 1-2%.

　　(1) Water-soluble content

　　The water-soluble content requires the help of solid dispersion technology. The functional substance can be made into powder by freeze-drying method, dispersed in PEG with a molecular weight of 400-4000 to form a slurry and then coated with gelatin to form empty gelatin capsules. The empty capsule made of PEG400 has a relatively fast drying process. If the drying time is too long, the shell will break, and if the drying time is too short, the empty capsule will leak during storage. In addition, PEG400 has a hardening effect on the rubber shell, adding 5-10% glycerin or propylene glycol can reduce the hardness and improve the effect of PEG400 on the rubber shell. If 2% or 3% PEG600 or PVP30 is used instead of PEG400, it can prevent temperature-dependent sol denaturation below 40 degrees Celsius.

　　(2) Water-insoluble content

　　Insoluble water-soluble drug oil, commonly used vegetable oil, is dispersed and dissolved by adding surfactants or other absorption enhancers to make an empty capsule. The drug in it is dispersed in the oil in a molecular state. It can spontaneously form an emulsion, enter the blood through the lymph, and is not affected by the first-pass effect, resulting in high bioavailability. Using surfactants such as polyglycerol esters and sucrose esters to make empty capsules can achieve high efficiency and high safety. For example, the bioavailability of erythromycin stearate added to polyglycerol esters is also higher than that of ordinary preparations. several times higher.