The Medical Properties of Fumed Silica
Fumed silica is widely used in medical field, mainly in pharmaceuticals and medical organic silicon materials. For example, infusion tube, oxygen mask, medical catheter, artificial organ and cosmetic surgery materials.
As drug absorption enhancer, the most important property is good physical and chemical stability. Lots of lab test results prove that fumed silica with high dispersion may not be absorbed when in digestive tract or when used as trauma drugs, the reason for this is the low solubility when PH value is between 2 to 8, and another possibility is that something prevent silica from going through intestinal wall, so no change related to silica is found in blood when drugs are taken. With good physical and chemical stability, fumed silica is quite qualified as drug carrier.
The average partical size of fumed silica is around 15nm, there are lots of oxhydryl and unsaturated atoms on the surface of fumed silica, which makes fumed silica tend to absorb water and charged substances, those water and substance form gel layer on its surface, the thickness of the layer depends on the partical surface property and the composition of the absorbed substance. Due to the above property, fumed silica can be added into desiccant in dermatology to eliminate edema and relieve inflammation.
Fumed silica with high dispersion property has strong reaction with disease-causing bacteria like E. coil, staphylococcus, it can fix the position of most microorganisms in a short time, no matter what kind of the microorganisms is. Firstly, the partical size of fumed silica is 7nm to 40 nm, while microorganism is 1um to 10um, the former one is much more smaller, and this makes fumed silica easy to aggregate, it improves absorption property of microorganism; Secondly, when microorganism reacts with fumed silica, it trends to be highly sensitive to antibiotics like penicillin and streptomycin, this contributes to reducing dosage of antibiotics.
As we can figure out from above, fumed silica has great potential in medical application due to its special properties.It can be added into external pharmaceuticals to treat inflammation, eczema, allergic dermatitis, it can also be used as inner adsorbents to treat pancreatitis, intestinal infection,pleurisy,cellulitis, hepatitis, gynecologic inflammation and to decrease side effect in tumour chemotherapy.
With the development of fumed silica manufacturing technology, the application of fumed silica is of tremendous market potential and will goes further in medical field.