A novel approach for dermal controlled release of salicylic acid for improved anti-inflammatory action: Combination of hydrophilic-lipophilic balance and response surface methodology

Insights from a Box–Behnken Optimization Study of Microemulsions with Salicylic Acid for Acne Therapy

“…The solubilization effect of the stabilizer mixture and oil phase for salicylic acid was considered interesting to be studied in further experiments by selecting a larger concentration domain of oil phase. By reference to the study of Sinha P. et al, salicylic acid 1% was solubilized in lemongrass oil and then combined with a mixture of Tween 80 and Labrasol in order to obtain nanoemulsified systems for acne therapy purposes [19]. A shortcoming of their study which can also be considered in the present case, was supposed to be the lack of implementing the standard method based on the pseudoternary phase diagram design, which can offer a general and useful perspective upon the stable areas of microemulsions and differentiation between unstable dispersions.…”

“…Formulated in classical skin care products such as lotions [17], or ointments [18], it tends to localize in the upper layers of the skin, offering in this case a superficial exfoliating effect. Current interests highlight the importance of targeted therapy as a way to overcome the diffusional barrier of stratum corneum to promote a deeper localization of lipophilic compounds and access the affected sites [19]. Recent advances have revealed strategies to improve salicylic acid action at skin level and alleviate its irritative potential, and here can be classified a number of modern colloidal systems, namely: nanoparticles [20,21], nanoemulsions [19], and microemulsions [22].…”

“…Current interests highlight the importance of targeted therapy as a way to overcome the diffusional barrier of stratum corneum to promote a deeper localization of lipophilic compounds and access the affected sites [19]. Recent advances have revealed strategies to improve salicylic acid action at skin level and alleviate its irritative potential, and here can be classified a number of modern colloidal systems, namely: nanoparticles [20,21], nanoemulsions [19], and microemulsions [22]. Older studies reported also the possibility to encapsulate salicylic acid in liposomal formulations [23], hydrogels, or lipogels [18].…”

“…Thus, several techniques can be mentioned, particularly response surface methodology (RSM) which encompasses statistical analysis of response, factorial plotting, contour and surface plotting, with the possibility of assessing predictive responses based on the response optimizer tool [67,68]; subsequently, alternative practical analyses such as Mixture design [69] and the Taguchi approach [70,71] can also be implemented. Mathematical modeling was considered a useful tool to explain the impact of formulation factors on the physical properties of microemulsions, as previously reported [19,21,67].…”

A Review: Anti-Cancer Natural Product Drug Delivery System Dosage Form and Evaluation

“…The polydispersity index (PDI) is a measure of the width of size distribution, which is a dimensionless quantity. A small value of PDI indicates a monodispersed population, while a large PDI indicates a broader distribution of particle size [60]. PDI is also used to indicate particle size homogeneity [23].…”