Calcium phosphate nanoparticles are promising non-viral vectors for gene therapy, an emerging strategy for effective bone repair and regeneration. The calcium phosphate naturally present in bones makes calcium phosphate nanoparticles a good choice for RNA delivery for bone repair. There is particular interest in the use of calcium phosphate nanoparticles with RNAi to regulate gene expression in bone tissue engineering because of their osteoinductivity, osteoconductivity, and affinity for nucleic acids. Calcium phosphate nanoparticles are endocytosed by cells and dissolve in the acidic endosomes and lysosomes resulting in the release of the nucleic acid cargo. Calcium phosphate nanocarriers are biocompatible, biodegradable, non-toxic and non-immunogenic, inexpensive, and easily synthesized. However, they become unstable over time because of the growth of crystals 362 , and they provide only limited nuclease protection. Surface functionalization of calcium phosphate particles can facilitate their endocytosis and subsequent endosomal escape. Although many vehicles or ligands have been used for the delivery of nucleic acids, they may exhibit low immunocompatibility, toxicity, poor stability, inefficient drug release, or restricted tissue accessibility. 366 However, RNA itself can self-assemble into complex programmable structures. Ligand-conjugated RNA nanoparticles based on bacteriophage phi29 packaging RNA provide a targeted ribozyme delivery system. 369 RNA nanoparticles can also carry CpG DNA to macrophages. Origamilike RNA nanostructures are stable and efficient as drug carriers for controlled drug release. Virus-like particles (VLPs) are organized protein complexes resembling a native virus capsid. VLPs are either naturally occurring empty virus shells or are synthesized by the expression of viral structural proteins that self-assemble into a virus-like structure. VLPs are attractive drug delivery platforms due to their biocompatibility, biodegradability, and targeting ability. VLPs produced in vivo are used for various medical applications such as drug and vaccine delivery 373 , including the COVID-19 vaccine Novavax (NVX-CoV2373) currently in phase III trials . In vivo and in vitro cargo loading has been demonstrated for VLPs. Quantum dots (QDs) are semiconductor crystalline nanoparticles with unique tunable optical properties including nearly 100-fold greater brightness and 1000-fold better stability against photobleaching versus organic dyes and luminescent proteins. Their fluorescence emission can be adjusted by the particle size, known as the quantum size effect. QDs emit narrow wavelength bands under a wide excitation range, can be appropriately functionalized, and are desirable vectors for imaging-guided therapy. Since they can efficiently deliver RNAs into target cells and can be used to track the RNA distribution in cells 377 , they may serve as an effective theranostic RNA delivery agent. The application of theranostic agents with appropriate targeted, controlled delivery and imaging capabilities has the potential to significantly advance gene therapy.