Surfactant effects upon dissolution patterns of carbamazepine immediate release tablet

Area of Science:

• Pharmaceutical Sciences
• Physical Chemistry
• Drug Delivery

Background:

• Carbamazepine is an important antiepileptic drug with variable bioavailability.
• Dissolution rate is a critical factor influencing drug absorption and therapeutic efficacy.
• Sodium lauryl sulfate (SLS) is a surfactant commonly used to enhance drug solubility and dissolution.

Purpose of the Study:

• To investigate the impact of sodium lauryl sulfate (SLS) concentrations on carbamazepine's saturation solubility.
• To analyze the effect of SLS on carbamazepine's dissolution kinetics and T50% (time for 50% dissolution).
• To determine if SLS concentration can be optimized to control carbamazepine dissolution profiles.

Main Methods:

• Carbamazepine dissolution was studied in water, 0.1 N HCl, and phosphate buffers (pH 4.0, 6.8) with varying SLS concentrations (0.1% to 2%).
• Dissolution tests were performed using USP apparatus II at 75 rpm.
• Carbamazepine concentrations were measured spectrophotometrically at 285 nm, and data fitted to a four-parameter exponential equation.

Main Results:

• Carbamazepine dissolution rate increased proportionally with increasing SLS concentration in the dissolution media.
• T50% values decreased as SLS concentration increased, with a rapid decline between 0.1% and 0.5% SLS.
• The four-parameter exponential equation accurately described the dissolution data, allowing calculation of dissolution rates and T50%.

Conclusions:

• Sodium lauryl sulfate significantly enhances the dissolution rate of carbamazepine.
• The concentration of SLS in dissolution media can be optimized to tailor carbamazepine's dissolution profile and testing duration.
• These findings have implications for formulation development and quality control of carbamazepine products.