Development of Local Injectable Dental Gel: The Influence of Certain Additives on Physicochemical Properties of Glycerylmonooleate‐Based Formulations

The current research study is based on the design and development of a sol‐gel biodegradable controlled‐release formulation for use in the treatment of periodontal diseases. Glycerylmonooleate (GMO) was used as a main composition in the gel base. The influence of various additives, e.g., glycerylmonostearate (GMS), methylcellulose (MC), surfactants, and triglycerides, in GMO formulations on rheologic and swelling properties and release characteristics was described. It was demonstrated that the surfactants and triglycerides affected rheologic behavior, whereas GMS and MC influenced both rheologic and swelling properties of the bases. The release study revealed that drug released from the gel bases depended on the square root of time. The kinetics can be explained by the Higuchi's diffusion theory. Some polyols could enhance drug release from the gel. The stability results suggested that the dental gels obtained should be kept in the low temperature range.     

温度对HSG冻胶体系流变性的影响

测量了HSG冻胶体系的屈服应力、蠕变-回复和粘弹性参数，研究了温度对其流变性的影响．结果表明，HSG冻胶体系的屈服应力随着温度的升高而明显下降，超过冻胶体系屈服应力之后很快达到稳定的平衡应力值，温度对其影响很小．温度越高，冻胶的柔量越大，越易变形．HSG冻胶体系具有高弹低粘特性，随着温度的升高、冻胶弹性明显下降，但粘性下降不大．温度越高、冻胶线性粘弹性区域越小．     

Combining strategies to optimize a gel formulation containing miconazole: the influence of modified cyclodextrin on textural properties and drug release

Background: Miconazol, an antimycotic drug, is commonly formulated into semisolid formulations designed to be applied in the oral cavity to treat oral candidiasis. However, given its limited aqueous solubility, permeation through the biological membranes is low and therefore its activity is also limited. Cyclodextrins (CDs) have been widely used to increase the solubility and stability of poorly water-soluble drugs. Aim: The aim of this study is to formulate a gel containing an inclusion complex between a modified CD, methyl-β-cyclodextrin (MβCD), and miconazole (MCZ). The influence of the CD on the textural properties of the prepared gel and the drug release from formulation were evaluated. Methods: The gels were prepared using two polymers, Carbopol 71G and Pluronic F127, which were selected taking into account their bioadhesiveness and thermal-sensitive gelling properties, respectively. Texture profile analyses were performed at two different temperatures to ascertain the influence of the temperature on the gel texture properties. The in vitro MCZ release profiles from the prepared gel and the commercial gel formulations were evaluated and compared using modified Franz diffusion cells. Results: The addition of MβCD to the gel resulted in a decrease of the gel adhesiveness and firmness, and the MCZ release profile through f1 and f2 proved to be similar to the commercial product. Conclusions: A gel comprising miconazol in the form of an inclusion complex with MβCD showed suitable textural properties to be applied to the buccal mucosa. The MβCD enhanced the solubility of the MCZ in the gel formulation resulting in adequate in vitro drug release profiles.     

Vegetable oils as core of cationic polymeric nanocapsules: influence on the physicochemical properties

Vegetable oils might be alternatives to mineral or synthetic oils used in nanostructured systems for cutaneous application, due to their advantages with regard to skin care and protection. In this study, we propose the use of vegetable oils (Brazil nut, sunflower seed, olive, rose hip, grape seed and carrot oils) as oily core of Eudragit RS100® nanocapsules and determine their influence on the physicochemical properties of those nanoparticles, in comparison with nanocapsules with capric/caprylic triglycerides as oily core. The formulations containing vegetable oils as core presented pH values suitable for topical application, average diameter close to 280?nm (SPAN around 2.5) and zeta potential close to +7?mV, due to the cationic properties of the polymer. Their viscosities were not affected by the type of oil used as core. By means of multiple light scattering, a reversible particle creaming phenomenon was observed for all the formulations. The nanocapsules prepared using Brazil nut, sunflower seed, olive, grape seed, rose-hip and carrot oils presented some distinct physicochemical properties when compared to nanocapsules obtained with capric/caprylic triglycerides: a higher size and SPAN value, a lower number of particles and a higher tendency to reversible creaming. Those findings are probably related to the lower density and higher viscosity of the vegetable oils.