Wojciechowska, Katarzyna, et al. Current Issues in Pharmacy and Medical Sciences 27.4 (2014): 224-228.
The efficacy of topically applied bioactive compounds, such as caffeine in anti-cellulite products, is significantly influenced by the vehicle's ability to release the active ingredient effectively. This study examined the performance of methyl glucose sesquistearate (MGS) as the emulsifier in a series of oil-in-water creams, evaluating its role in determining the physical properties and caffeine release rates from formulations containing six different vegetable oils.
Formulations: Methyl glucose sesquistearate was utilized as the key emulsifier in all six cream formulations. Each cream contained 5% caffeine and was based on a different oil phase: Sesame oil, Rice oil, Walnut oil, Coconut oil, Sweet almond oil, or Jojoba oil. A standard preparation method was followed: MGS was combined with cetyl alcohol and the specific oil to form the oil phase (Phase 2), which was then added to an aqueous phase containing dissolved caffeine (Phase 1). The mixture was homogenized to form a uniform cream.
Key Results:
· Physical testing revealed differences in slippage and spreadability among the formulations, with the Coconut oil-based cream demonstrating the best parameters in these tests.
· All six creams stabilized with MGS displayed pseudoplastic (shear-thinning) flow behavior, fitting the Ostwald de Waele power law model. The flow index (n) ranged from 0.2467 to 0.3179 at 20°C. Thixotropic behavior was observed in some formulations at 20°C but was largely absent at 32°C, except in the Walnut oil-based cream.
· Caffeine release studies showed a significant variance dependent on the oil carrier. The Jojoba oil-based cream facilitated the highest caffeine release (85.23% ± 0.8%), while the Coconut oil-based cream resulted in the lowest release (62.78% ± 0.87%).
Bîrsan, Magdalena, et al." Cosmetics 12.5 (2025): 195.