Cellulose Functionalized Nano-Hydroxyapatite

Archive: https://archive.is/eDIiL 

https://archive.is/gPKEG

In our last post we talked about combining nano hydroxyapatite with cellulose.  This invention is similar, growing the nano or micro hydroxyapatite on regenerated or nano or micro cellulose or any other fibrous molecule including collagen or keratin or starch or anything else.

To create nano hydroxyapatite we combine an ionic calcium and ionic phosphate at a 1.67:1 molar ratio (respectively) and then raise the pH to roughly 10 to cause the calcium and phosphorus to precipitate into nano crystals.  

To functionalize it, you can have an added ingredient added either to one or both of the solutions above in any order at any time using any protocol to make nano hydroxpapatite.  In our case now cellulose is our added ingredient.  The cellulose or other fibrous molecule or anything else can be modified in any way if desired to enhance mineralization with hydroxyapatite.

For an example we can combine ionic calcium and ionic phosphorus solution while stirring.  Next we can add regenerated cellulose.  Then we can stir and then add dropwise an alkaline solution like ammonium hydroxide or potassium hydroxide or sodium hydroxide or any alkaline soluble solution.  This will cause the hydroxyapatite to use the cellulose particles as seeds to grow on, and the cellulose will also likely be mineralized entirely in this process.

My current process for nHAp is:

Combine: 

Calcium nitrate tetrahydrate 70.84g
Phosphoric acid 85% 12.32mL

In 500mL distilled H2O, then add: 

KOH 40g in 500mL added dropwise during stirring

Theoretical yield 30g nHAp

Silica can also be added as a functionalizing particle, and soluble silica solutions can be added at any step in hydroxyapatite manufacture as well.

Other ingredients like citric acid, glycine or any other amino acid or protein or mixture thereof of natural or artificial origin, other cations like magnesium or zinc, or anything else can also be used to substitute into the nano-hydroxyapatite crystal by addition of soluble solutions at any point in the nano hydroxyapatite manufacture.  The nano-hydroxyapatite spoken of can be produced by any method including wet precipitation, sol gel, or any other method to produce hydroxyapatite. 

And of course like all of my inventions, this can be used for any purpose whatsoever including but not limited to dentifrice like teeth powder and toothpaste and mouthwash and gel etc to water purification and anything else.

functionalizing cellulose https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.201800409

cellulose binding cations https://www.sciencedirect.com/science/article/abs/pii/0308814694901198

cellulose alkaline hydroxides https://www.semanticscholar.org/paper/INTERACTION-OF-CELLULOSE-WITH-ALKALI-METAL-IONS-AND-%C3%96zt%C3%BCrk-Vu-Manh/f02d45ba23ecfb155b0f2639510ef4014358b9f7?p2df

Nano dispersed regenerated cellulose

https://pubs.rsc.org/en/content/articlehtml/2019/ta/c8ta09959f