Nanotechnology provides an excellent platform for the development of a new generation of vaccines. These are based on purified subunit proteins or polysaccharides, recombinant proteins, synthetic peptides, or nucleic acids. These types of vaccines may be insufficiently immunogenic, thus requiring adjuvants that augment their immunogenicity. Nanoparticles (NPs) can act as adjuvants for vaccines, hence they are referred to as a nano-adjuvant (NA). NPs can either encapsulate or adsorb the vaccine antigen or DNA in an appropriate formulation, thus increasing stability, cellular uptake, and immunogenicity. In addition, the biodistribution and systemic release of a vaccine can also be controlled by different NA formulations. This review provides an overview of the classification of NAs and also addresses factors influencing the stability, release, and immunogenicity of the formulated vaccine. A basic understanding of these factors enables a more rational design of NA formulations. Applications of NAs and key challenges in their formulation development are also discussed.

中文翻译：

---

纳米颗粒作为疫苗递送中的佐剂。

纳米技术为开发新一代疫苗提供了绝佳的平台。它们基于纯化的亚基蛋白或多糖、重组蛋白、合成肽或核酸。这些类型的疫苗可能免疫原性不足，因此需要佐剂来增强其免疫原性。纳米颗粒（NPs）可以作为疫苗的佐剂，因此被称为纳米佐剂（NA）。NPs 可以在适当的配方中封装或吸附疫苗抗原或 DNA，从而提高稳定性、细胞吸收和免疫原性。此外，疫苗的生物分布和全身释放也可以由不同的 NA 制剂控制。本综述概述了 NAs 的分类，并讨论了影响稳定性、释放、和配制疫苗的免疫原性。对这些因素的基本了解有助于更合理地设计 NA 配方。还讨论了 NA 的应用及其制剂开发中的关键挑战。