Carbonate Ion → Levobupivacaine

Participants

Reaction Steps

In a first vial, levobupivacaine-HCl (6, 12.5 or 25 mg), tetrafunctional PEG, pentaerythritol poly(ethylene glycol) ether tetra-N-hydroxy-succinimidyl glutarate (10,000 g/mol) (SG-PEG) (50 mg) and tetrafunctional PEG, pentaerythritol poly(ethylene glycol) ether tetra-sulfhydryl (10,000 g/mol) (PEG-SH) (50 mg) were dissolved in 250 μL of pH 2.2 buffer. This solution was combined with an equal volume of carbonate buffer (pH 9.7) using a spray kit. Levobupivacaine precipitated within the gel upon mixing. All levobupivacaine-loaded gels swelled 1.5-2 times their original volume except for the gel containing the highest amount of levobupivacaine, which swelled about 4 times its initial volume. In vitro release studies showed a steady release of levobupivacaine from the gel. At 9 days, 30% of the drug was released.

Provenance & Evidence