73
protocol copolymer and drug are first dissolved in a common
organic solvent to appropriate quantities. The final mixture of
polymer and drug is added all at once to a predefined volume of
filtered Milli-Q water under vigorous stirring and removal of
organic solvent by evaporation follows. Some guidelines regarding
the physicochemical characterization of the micelle/drug formulations using a gamut of techniques are also given.
The incorporation of curcumin into Pluronic F-127 micelles
has proved to be more effective through the thin-film hydration
protocol than through organic cosolvent mixing/evaporation process, primarily in terms of achieving high encapsulation efficiencies
[17–19]. Both encapsulation protocols are also used in creating
indomethacin-loaded PEO-b-PCL micelles in order to compare
these protocols and determine the safest and more efficient one for
developing a drug delivery nanovehicle. The difference between
the two protocols utilized, depends on when the organic solvent
evaporation takes place.
2 Materials
Pluronic F-127 (Mw = 12.600 g.mol
−1
) from Sigma-Aldrich,
poly(ethylene oxide)-b-poly(ε-caprolactone) (PEO-b-PCL with
30% PCL, M w = 7500 g.mol
−1
, synthesized in house by ringopening polymerization and using PEO from Sigma Aldrich,
M w = 5000 g.mol
−1
), curcumin (keto form) from Merck,
indomethacin (IND) from Fluka, tetrahydrofuran (THF,
99.9%), acetone (>99.5%), Milli-Q H 2 O.
Prepare all solutions using Milli-Q H 2 O (alternatively water for
injection can be used) and analytical grade reagents. Prepare and
store all reagents at room temperature (unless indicated otherwise).
3 Methods
Carry out all procedures at room temperature unless otherwise
specified. In the case of curcumin, experiments for the encapsulation of 50% and 100% w/w drug relative to the hydrophobic core
were attempted, while in the case of indomethacin experiments for
the encapsulation of 20%, 50%, and 100% w/w drug relative to the
hydrophobic core were attempted (see Note 1).
1. In a glass vial weigh 10 mg Pluronic F-127 and add 1 mL
acetone. Wait for the polymer to dissolve (as inspected
visually).
2. In a second vial, weigh 1.5 mg curcumin and add 200 μL
acetone. Wait for the drug to dissolve (as inspected visually).
3.1 Solution
of Pluronic F-127
with 50% Curcumin
Encapsulated (Organic
Cosolvent Protocol)
Drug Delivery: Hydrophobic Drug Encapsulation into Amphiphilic Block…
protocol copolymer and drug are first dissolved in a common
organic solvent to appropriate quantities. The final mixture of
polymer and drug is added all at once to a predefined volume of
filtered Milli-Q water under vigorous stirring and removal of
organic solvent by evaporation follows. Some guidelines regarding
the physicochemical characterization of the micelle/drug formulations using a gamut of techniques are also given.
The incorporation of curcumin into Pluronic F-127 micelles
has proved to be more effective through the thin-film hydration
protocol than through organic cosolvent mixing/evaporation process, primarily in terms of achieving high encapsulation efficiencies
[17–19]. Both encapsulation protocols are also used in creating
indomethacin-loaded PEO-b-PCL micelles in order to compare
these protocols and determine the safest and more efficient one for
developing a drug delivery nanovehicle. The difference between
the two protocols utilized, depends on when the organic solvent
evaporation takes place.
2 Materials
Pluronic F-127 (Mw = 12.600 g.mol
−1
) from Sigma-Aldrich,
poly(ethylene oxide)-b-poly(ε-caprolactone) (PEO-b-PCL with
30% PCL, M w = 7500 g.mol
−1
, synthesized in house by ringopening polymerization and using PEO from Sigma Aldrich,
M w = 5000 g.mol
−1
), curcumin (keto form) from Merck,
indomethacin (IND) from Fluka, tetrahydrofuran (THF,
99.9%), acetone (>99.5%), Milli-Q H 2 O.
Prepare all solutions using Milli-Q H 2 O (alternatively water for
injection can be used) and analytical grade reagents. Prepare and
store all reagents at room temperature (unless indicated otherwise).
3 Methods
Carry out all procedures at room temperature unless otherwise
specified. In the case of curcumin, experiments for the encapsulation of 50% and 100% w/w drug relative to the hydrophobic core
were attempted, while in the case of indomethacin experiments for
the encapsulation of 20%, 50%, and 100% w/w drug relative to the
hydrophobic core were attempted (see Note 1).
1. In a glass vial weigh 10 mg Pluronic F-127 and add 1 mL
acetone. Wait for the polymer to dissolve (as inspected
visually).
2. In a second vial, weigh 1.5 mg curcumin and add 200 μL
acetone. Wait for the drug to dissolve (as inspected visually).
3.1 Solution
of Pluronic F-127
with 50% Curcumin
Encapsulated (Organic
Cosolvent Protocol)
Drug Delivery: Hydrophobic Drug Encapsulation into Amphiphilic Block…