Aluminum-containing salts are commonly used as antacids and vaccine adjuvants; however, key features of functional activities remain unclear. Here, we characterized vaccine formulations based on aluminum phosphate and aluminum hydroxide and investigated the respective modes of action linking physicochemical properties and catalytic ability. TEM microscopy indicated that aluminum phosphate gel solutions are amorphous, whereas aluminum hydroxide gel solutions have a crystalline structure consistent with boehmite. At very low BSA concentrations, 100% adsorption of the protein on aluminum hydroxide could be achieved. As the protein concentration increased, the amount of adsorbed BSA decreased as fewer vacant sites were available on the surface of the adjuvants. Notably, less than 20% adsorption was observed in aluminum phosphate. The protein adsorption profiles should confront the requirements for vaccine immunoavailability. In terms of catalytic ability, the prepared aluminum salts were tested for their ability to drive the amphiphilic engineering of oligo(lactic acid) (OLA) onto methoxy poly(ethylene glycol). It was concluded that aluminum hydroxide, rather than aluminum phosphate, is suitable to be a vaccine adjuvant according to the morphology and antigen adsorption efficiency results; on the other hand, aluminum phosphate may be a more efficient catalyst for the synthesis of polymeric emulsifiers than aluminum hydroxide. The results provide critical mechanistic insight into aluminum-containing salts in vaccine formulations.

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磷酸铝和氢氧化铝的形态和蛋白质吸附及其在聚合乳化剂合成中的潜在催化作用

含铝盐常用作抗酸剂和疫苗佐剂；然而，功能活动的关键特征仍不清楚。在这里，我们对基于磷酸铝和氢氧化铝的疫苗制剂进行了表征，并研究了将理化特性和催化能力联系起来的各自作用模式。TEM 显微镜表明磷酸铝凝胶溶液是无定形的，而氢氧化铝凝胶溶液具有与勃姆石一致的晶体结构。在非常低的 BSA 浓度下，可以实现蛋白质在氢氧化铝上的 100% 吸附。随着蛋白质浓度的增加，吸附的 BSA 量减少，因为佐剂表面可用的空位减少。值得注意的是，在磷酸铝中观察到不到 20% 的吸附。蛋白质吸附曲线应满足疫苗免疫利用度的要求。在催化能力方面，测试了制备的铝盐将低聚（乳酸）（OLA）两亲工程驱动到甲氧基聚（乙二醇）上的能力。根据形态和抗原吸附效率结果，得出氢氧化铝而不是磷酸铝更适合作为疫苗佐剂的结论；另一方面，磷酸铝可能是比氢氧化铝更有效的聚合乳化剂合成催化剂。结果提供了对疫苗制剂中含铝盐的关键机理洞察。测试了制备的铝盐将低聚（乳酸）（OLA）两亲工程驱动到甲氧基聚（乙二醇）上的能力。根据形态和抗原吸附效率结果，得出氢氧化铝而不是磷酸铝更适合作为疫苗佐剂的结论；另一方面，磷酸铝可能是比氢氧化铝更有效的聚合乳化剂合成催化剂。结果提供了对疫苗制剂中含铝盐的关键机理洞察。测试了制备的铝盐将低聚（乳酸）（OLA）两亲工程驱动到甲氧基聚（乙二醇）上的能力。根据形态和抗原吸附效率结果，得出氢氧化铝而不是磷酸铝更适合作为疫苗佐剂的结论；另一方面，磷酸铝可能是比氢氧化铝更有效的聚合乳化剂合成催化剂。结果提供了对疫苗制剂中含铝盐的关键机理洞察。根据形态和抗原吸附效率结果适合作为疫苗佐剂；另一方面，磷酸铝可能是比氢氧化铝更有效的聚合乳化剂合成催化剂。结果提供了对疫苗制剂中含铝盐的关键机理洞察。根据形态和抗原吸附效率结果适合作为疫苗佐剂；另一方面，磷酸铝可能是比氢氧化铝更有效的聚合乳化剂合成催化剂。结果提供了对疫苗制剂中含铝盐的关键机理洞察。