Lumen halloysite

A maximum loading of 5.5 wt% at pH 1 when both lumen and outermost surface are positive is close to full loading (about 12 vol% taking into account that the density of the clay is approximately twice that of the drug). Minimum 2 % loading was at pH 9 when both halloysite lumen and Dexamethasone have the same negative charge. 

Fig. 14.12 Nanoparticle co-loading 10-nm silica inside halloysite lumen.

A strong surface charge on the halloysite tubules has been exploited for designing nano-organized multilayers using the layer-by-layer (LbL) method of Lvov et al. [8,13,14]. The lumen of the halloysite has been used as an enzymatic nano-reactor by Shchukin et al. [15] The biocompatible nature of the halloysite was... 

Nanoassembly on Tubules and at the Lumen Opening 429 % Releases of proteins from Halloysite assisted with PEI... 

CaC03 precipitation is clearly visible in Figure 14.14, which is a TEM image of halloysite cross-sections. Halloysite has >90% of the tubular form with outer diameter 50 5nm and inner diameter of the lumen 15 nm. The length of the initial halloysite is less than 1 micron, which results in a substantially short diffusion path length. The calculated value of the free inner space indicates the ability to load a maximum 14 3 % of the total volume ofthe halloysite. The entrapment efficiency of 5 % by volume was estimated. 

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