Objective

Agglomeration is a common problem facing the preparation and application of nanomaterials, and whether nano-hydroxyapatite (nano HA) can modulate oral microecology left to be unclear. In this study, nano HA was disaggregated by sodium hexametaphosphate (SHMP) and ultrasonic cavitation to observe whether agglomeration would affect its effect on oral bacterial biofilm.

Methods

Dynamic light scattering (DLS) and scanning electronic microscope (SEM) were used to observe the treatment solutions. Single-species biofilms and multi-species biofilms were treated with 10% nano HA, 10% disaggregated nano HA, 10% micro hydroxyapatite (micro HA) and deionized water (DDW) for 30 min and analyzed via MTT assay, lactic acid measurement, SEM and confocal laser scanning microscope (CLSM). Real-time polymerase chain reaction was performed to analyze the biofilm composition.

Results

Ultrasonic cavitation combined with SHMP could significantly reduce the degree of agglomeration of nano HA. Disaggregated nano HA could inhibit bacterial growth and reduce the ability of bacterial biofilm to produce lactic acid and extracellular polysaccharides. There was no significant difference on composition of multi-species biofilms between nano HA and disaggregated nano HA.

Significance

The disaggregated nano-hydroxyapatite could inhibit the metabolism and acid production of oral bacterial biofilm, but did not significantly affect the composition of multi-species biofilms.

中文翻译：

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体外分解纳米羟基磷灰石对口腔生物膜的影响。

目的

团聚是纳米材料的制备和应用面临的普遍问题，尚不清楚纳米羟基磷灰石（nano HA）是否可以调节口腔微生态。在这项研究中，纳米HA被六偏磷酸钠（SHMP）和超声空化分解，以观察团聚是否会影响其对口腔细菌生物膜的影响。

方法

使用动态光散射（DLS）和扫描电子显微镜（SEM）观察处理溶液。用10％纳米HA，10％分解纳米HA，10％微型羟基磷灰石（micro HA）和去离子水（DDW）处理单物种生物膜和多物种生物膜30分钟，并通过MTT分析，乳酸测量， SEM和共聚焦激光扫描显微镜（CLSM）。进行实时聚合酶链反应以分析生物膜组成。

结果

超声空化结合SHMP可以显着降低纳米HA的团聚程度。分解的纳米HA可以抑制细菌生长，并降低细菌生物膜产生乳酸和细胞外多糖的能力。纳米HA和分解纳米HA之间的多物种生物膜组成没有显着差异。

意义

分解的纳米羟基磷灰石可以抑制口腔细菌生物膜的代谢和产酸，但对多种生物膜的组成没有明显影响。