J Am Dent Assoc. 2019 Apr;150(4S):S5-S13. doi: 10.1016/j.adaj.2019.01.004.
Stannous fluoride (SnF) is a compound present in many commercially available dentifrices; however, oxidative decomposition negatively impacts its efficacy. Stannous oxidation is often mitigated through the addition of complexing agents or sources of sacrificial stannous compounds. The authors have found that the addition of zinc phosphate significantly improved stannous stability more effectively than other stabilization methods. The authors evaluated the chemical speciation of stannous compounds within a variety of formulations using x-ray absorption near edge spectroscopy (XANES), a technique never used before in this manner. These data were compared and correlated with several antimicrobial experiments.
XANES data of various commercially available compounds and Colgate Total were performed and analyzed against a library of reference compounds to determine the tin chemical speciation. The antibacterial assays used were salivary adenosine triphosphate, short-interval kill test, plaque glycolysis, and anaerobic biofilm models.
XANES spectra showed a diverse distribution of tin species and varying degrees of SnF oxidation. In vitro antimicrobial assessment indicated significant differences in performance, which may be correlated to the differences in tin speciation and oxidation state.
Driven by the excipient ingredients, SnF dentifrices contain a distribution of tin species in either the SnF or Sn(IV) oxidation state. The addition of zinc phosphate provided significant robustness against oxidation, which directly translated to greater efficacy against bacteria.
The choice of inactive ingredients in a dentifrice with active SnF can dramatically impact product stability.
氟化亚锡（SnF）是许多市售牙膏中含有的一种化合物；然而，氧化分解会降低其功效。通过添加络合剂或牺牲性锡化合物的来源，可以减轻锡的氧化。作者发现，添加磷酸锌可更有效地提高亚锡的稳定性，效果优于其他稳定方法。作者使用 X 射线吸收近边光谱（XANES）技术，以前从未以这种方式评估过各种配方中亚锡化合物的化学形态，评估了多种配方中亚锡化合物的化学形态。这些数据与几种抗菌实验进行了比较和关联。
对各种市售化合物和高露洁全效进行了 XANES 数据分析，并与参考化合物库进行了对比，以确定锡的化学形态。使用的抗菌测定法有唾液三磷酸腺苷、短间隔杀灭试验、菌斑糖酵解和厌氧生物膜模型。
XANES 光谱显示锡物种分布多样，SnF 氧化程度不同。体外抗菌评估表明性能存在显著差异，这可能与锡形态和氧化态的差异有关。
受赋形剂成分的驱动，含 SnF 的牙膏中含有 SnF 或 Sn（IV）氧化态的锡物种分布。添加磷酸锌可显著增强抗氧化性，从而直接提高对细菌的功效。
含活性 SnF 的牙膏中赋形剂成分的选择会极大地影响产品的稳定性。
