Institute of Pharmacy, Department of Pharmaceutical Technology, University of Hamburg, Hamburg, Germany.
Drug Dev Ind Pharm. 2012 Apr;38(4):462-7. doi: 10.3109/03639045.2011.611806. Epub 2011 Oct 1.
In solid oral dosage forms silicates are commonly used as glidants in low concentration. However, due to their large specific surface area, silicates may also be used as carrier materials for drugs. Moreover, silicates allow amorphisation of drugs by co-grinding or processing with supercritical fluids.
The aim of this study was to investigate the physical and the tableting properties of Silica Aerogel (special type of silica with an extremely large specific surface area), Neusilin(®) US2 (magnesium aluminometasilicate), Florite(®) (calcium silicate) and Aerosil(®) 200 (colloidal silica).
Powder blends of Avicel(®) PH102 (microcrystalline cellulose) and different amounts of the respective silicate were compacted and analyzed for their tabletability (tensile strength vs. compaction pressure) as well as their Heckel plot.
With Neusilin(®) the tabletability appeared to be independent of the silicate concentration, whereas with Florite(®) an increasing silicate concentration led to a higher tensile strength. In contrast, the addition of Silica Aerogel and Aerosil(®) resulted in a decrease of the tensile strength. With Aerosil(®) a maximum tolerable concentration of 20% [w/w] was determined. Plastic deformation of all powder blends decreased with increasing silicate concentration. This effect was most pronounced with Aerosil(®) and least with Florite(®).
Tablets with acceptable tensile strength were obtained with all plain silicates except for Aerosil(®). Therefore, these silicates may be used in tablet formulations, e.g. as carrier materials for liquid or amorphous drugs.
在固体制剂中，硅化物通常以低浓度用作助流剂。然而，由于其比表面积较大，硅化物也可用作药物的载体材料。此外，硅化物允许通过共研磨或用超临界流体加工使药物无定形。
本研究的目的是研究硅石气凝胶（具有极大比表面积的特殊类型的硅）、Neusilin®US2（硅酸镁铝）、Florite®（硅酸钙）和 Aerosil®200（胶体二氧化硅）的物理和压片特性。
Avicel®PH102（微晶纤维素）和不同量的相应硅化物的粉末混合物进行压缩，并分析其可压性（拉伸强度与压缩压力的关系）和 Heckel 图。
使用 Neusilin®，可压性似乎与硅化物浓度无关，而使用 Florite®，硅化物浓度的增加导致拉伸强度增加。相比之下，添加硅石气凝胶和 Aerosil®导致拉伸强度降低。用 Aerosil®确定了最大可耐受浓度为 20%[w/w]。随着硅化物浓度的增加，所有粉末混合物的塑性变形都减少了。这种影响在 Aerosil®中最为明显，在 Florite®中最小。
除了 Aerosil®之外，所有普通硅化物都可获得具有可接受拉伸强度的片剂。因此，这些硅化物可用于片剂配方，例如作为液体或无定形药物的载体材料。
