User:Moira M. Esson/Notebook/CHEM-581/2013/02/15

(Difference between revisions)

Revision as of 20:18, 17 February 2013

Project name

Prepare PVA-clay microspheres.
Run diffusion tests on hydrogels prepared on 2013/01/30 with Rhodamine 6G dye added on 2013/02/08.

Due to the relatively unsuccessful preparation of PVA/clay microspheres(the prepared spheres were either larger than a micrometer or did not appear at all), a new method was used for the preparation of PVA/clay microspheres.

General Protocol:

The desired ratio of PVA and clay was measured out. The total mass was ~1g.
The PVA/clay was placed in a 50mL beaker with a magnetic stir bar. 25mL distilled H₂O were added to the beaker and the solution was heated to ~100°C and allowed to stir until complete dissolution of PVA/clay.
The magnetic stir bar was removed and 25mL of mineral oil was added to the beaker.
The contents of the beaker were poured into a blender to homogenize the solution and create an emulsion of the aqueous and organic layer in the attempt to create a suspension of microspheres.
The blender was turned on a low setting for 5 minutes.
The contents of the blender were poured into a beaker and the appropriate amount of DMSO/Rhodamine 6G solution was added.
The microsphere solution was placed in a freezer at -20°C for 24 hours and then removed and allowed to thaw for 24 hours.
Repeat this freeze-thaw cycle three times.

Preparation of Microspheres:

For a 90:10 ratio:

 (25mL)(1μM)/(92μM)=0.272mL

For a 50:50 ratio:

 (25mL)(1μM)/(165μM)=0.152mL

@@ Line 14: / Line 14: @@
 General Protocol:
 # The desired ratio of PVA and clay was measured out. The total mass was ~1g.
+# The PVA/clay was placed in a 50mL beaker with a magnetic stir bar. 25mL distilled H<sub>2</sub>O were added to the beaker and the solution was heated to ~100°C and allowed to stir until complete dissolution of PVA/clay.
+# The magnetic stir bar was removed and 25mL of mineral oil was added to the beaker.
+# The contents of the beaker were poured into a blender to homogenize the solution and create an emulsion of the aqueous and organic layer in the attempt to create a suspension of microspheres.
+# The blender was turned on a low setting for 5 minutes.
+# The contents of the blender were poured into a beaker and the appropriate amount of DMSO/Rhodamine 6G solution was added.
+# The microsphere solution was placed in a freezer at -20°C for 24 hours and then removed and allowed to thaw for 24 hours.
+# Repeat this freeze-thaw cycle three times.
+Preparation of Microspheres:
+*New calculations for the amount of DMSO/Rhodamine to be added:
+For a 90:10 ratio:
+  (25mL)(1μM)/(92μM)=0.272mL
+For a 50:50 ratio:
+  (25mL)(1μM)/(165μM)=0.152mL
+*Information about prepared microspheres: