Titanium Phosphate Glass Microspheres as Microcarriers for In Vitro Bone Cell Tissue Engineering - Biointerfaces: Where Material Meets Biology - page 111

5.2.3.3 Calcium Carbonate (CaCO 3 )

CaCO 3 - CaO þ CO 2

Mol. wt. (g mol 1 ) 100 56 44

d n 3 r 4 n g | 3

Relative mol. wt. (g mol 1 )

0.56 0.44

Amount of CaCO 3 to be added in order to obtain 40 mol% CaO:
¼ (0.4 56)/0.56 ¼ 40.00 g

5.2.3.4 Titanium Dioxide (TiO 2 )
Mol. wt. of Ti ¼ 47.90, and the amount of TiO 2 to be added in order to obtain
1 mol% TiO 2 :

¼ (47.90 þ 32) 0.01 ¼ 0.80 g

TIP: The amounts of precursors actually used to make the glass will depend on
the size of the Pt crucible. For smaller crucible sizes, half or one-third pre-
cursor quantities may be used.

5.2.4 Preparation of Glass Microparticles

CAUTION! Appropriate laboratory safety apparel such as laboratory coats,
goggles, nitrile/latex gloves and particulate respirator masks must be worn
throughout the entire procedure.

.

1. Switch on furnace and set the temperature to 700 1C.
2. Place an opened paddle blender bag into the 1000 mL plastic con-
tainer with its edges folded over the container rim. Place this con-
tainer on the weighing scale. Weigh the calculated amount of CaCO 3 ,
remove bag from container and keep aside. Repeat these steps for
NaH 2 PO 4 and TiO 2 .
3. Mix contents of all three bags into a separate bag. Place bag in paddle
blender and mix at 200 rpm for 1 min.
4. Repeat Step 1 for P 2 O 5 and then add P 2 O 5 to bag containing the other
precursors.

TIP: Since P 2 O 5 is highly hygroscopic in nature, perform this step as
quickly as possible to minimise water sorption. Repeat the mixing step.

5. Pour the mixed precursors into the crucible and place the crucible in
the preheated furnace using metal tongs