Zaklan Dragana, Davidović Nikola, Milutinov Jovana, Ćirin Dejan, Krstonošić Veljko, Pavlović Nebojša
Department of Pharmacy, Faculty of Medicine, University of Novi Sad, 21000 Novi Sad, Serbia.
Pharmaceutics. 2025 May 8;17(5):627. doi: 10.3390/pharmaceutics17050627.
Zinc oxide paste is traditionally compounded and applied in the therapy of various skin conditions. However, prolonged use of talc, usually present in zinc oxide pastes, may pose health risks due to potential contamination with asbestos and quartz, highlighting the need for alternative excipients. This study aimed to examine the effects of starches from various botanical sources and their particle size on the rheological and absorption properties of zinc oxide paste. Eight zinc oxide paste formulations were prepared, containing 25% zinc oxide and 25% indifferent excipient (talc, tapioca, rice, or maize starch) in two particle sizes. Rheological properties were assessed using amplitude and frequency sweep tests, and water- and oil-absorption capacities were determined using a centrifugation-based method. Amplitude sweep tests confirmed the predominant solid-like nature of zinc oxide pastes, with the elastic modulus (G') exceeding the viscous modulus (G″) in all formulations. Tapioca starch-based pastes exhibited the highest G' and G″ values, while talc-based pastes exhibited the lowest. Frequency sweep tests showed that pastes were resistant to structural changes under stress, with G' consistently dominating over G″ across the entire frequency range. Tapioca starch-based formulations exhibited the highest water-absorption capacity, while the talc-based formulations had the highest oil-absorption capacity. Reducing particle size improved both water- and oil-absorption capacities. Starches may be considered as alternatives to talc in zinc oxide pastes, due to their ability to modify the absorption and rheological properties of pastes. Future studies should assess the impact of starch substitution on sensory characteristics, shelf-life stability, and patient satisfaction.
氧化锌糊剂传统上是配制并应用于各种皮肤病的治疗。然而，氧化锌糊剂中通常含有的滑石粉若长期使用，可能因潜在的石棉和石英污染而带来健康风险，这凸显了寻找替代辅料的必要性。本研究旨在考察不同植物来源的淀粉及其粒径对氧化锌糊剂流变学和吸收性能的影响。制备了八种氧化锌糊剂配方，其中含有25%的氧化锌和25%的惰性辅料（滑石粉、木薯淀粉、大米淀粉或玉米淀粉），辅料有两种粒径。使用振幅扫描和频率扫描试验评估流变学性能，并采用基于离心的方法测定吸水和吸油能力。振幅扫描试验证实了氧化锌糊剂主要呈类固体性质，所有配方中的弹性模量（G'）均超过粘性模量（G″）。以木薯淀粉为基础的糊剂表现出最高的G'和G″值，而以滑石粉为基础的糊剂表现出最低值。频率扫描试验表明，糊剂在应力作用下抗结构变化，在整个频率范围内G'始终大于G″。以木薯淀粉为基础的配方表现出最高的吸水能力，而以滑石粉为基础的配方具有最高的吸油能力。减小粒径可提高吸水和吸油能力。由于淀粉能够改变糊剂的吸收和流变学性能，因此可考虑将其作为氧化锌糊剂中滑石粉的替代品。未来的研究应评估淀粉替代对感官特性、货架期稳定性和患者满意度的影响。
