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DNA-functionalized colloidal nanoparticles assemble through flexible, nanoscale DNA hybridization interactions that limit atomic-level structural order. Here, we report a valence-centric strategy that enables DNA-bonded, protein single crystals with unconventional mechanical properties. An octameric enzyme, glutarate L-2-hydroxylase, was site- and number-selectively conjugated with eight self-complementary single-stranded DNA, yielding octavalent molecular bonds. The resulting conjugate assembled into the designed body-centered tetragonal crystals that diffracted to 1.42- to 2.61-angstrom resolution, with contacts mediated by B-form DNA helices spanning 17 to 25 angstroms. Increasing oligonucleotide length induces anisotropic lattice expansion while preserving atomic periodicity, even with partial DNA occupancy. Mechanistic studies suggest that the dynamic motion of unhybridized DNA facilitates crystallization, analogous to fluctuating electron clouds in atomic bonding. Compared with native protein crystals, DNA-hybridized crystals are 23-fold softer. These results challenge the assumption that flexibility is incompatible with structural order and establish a programmable framework for biomolecular crystallization and nanomaterials engineering with atomic precision. 

Genome editing with CRISPR–Cas systems hold promise for treating a wide range of genetic disorders and cancers. However, efficient delivery of genome editors remains challenging due to the requirement for the simultaneous delivery or intracellular generation of Cas proteins, guide RNAs, and, in some applications, donor DNAs. Furthermore, the immunogenicity and toxicity of delivery vehicles can limit the safety and efficacy of genetic medicines. Here, we combine two nucleic acid delivery approaches to create CRISPR lipid nanoparticle–spherical nucleic acids (LNP–SNAs) that are both efficient and biocompatible. Compared to lipid nanoparticles (LNPs) lacking a surface-bound DNA shell, CRISPR LNP–SNAs exhibit two- to three-fold higher cellular uptake, reduced cytotoxicity, and improved gene transfection efficiency. Across multiple cell lines and genomic loci, CRISPR LNP–SNAs induce insertion–deletion mutations at average frequencies two- to three-fold higher than those observed with LNPs. When codelivered with donor templates, CRISPR LNP–SNAs enable homology-directed repair at an average efficiency of 21 ± 7%, a 2.5-fold improvement over LNPs (8 ± 4%). The ease of synthesis and biocompatibility of CRISPR LNP–SNAs highlight their potential as a versatile delivery platform for CRISPR–Cas and other gene therapies. 

ABSTRACT Spherical nucleic acids (SNAs) are nanostructures consisting of densely packed, radially oriented oligonucleotides arranged on nanoparticle cores. They are highly relevant to nanomedicine due to their unique physicochemical and biological properties, including efficient uptake across a broad range of cell types (over 50). This uptake is mediated in part by interactions between the oligonucleotide shell and scavenger receptors, making the DNA charge and sequence critical factors governing cellular internalization pathways. Recent advances in deoxynucleic guanidines (DNGs), nucleic acid analogues featuring positively charged guanidinium backbones, provide an opportunity to systematically probe how DNA charge influences SNA uptake. In this work, we report the synthesis of SNAs incorporating DNG‐DNA chimeras and evaluate how DNG incorporation alters SNA properties and cellular internalization. We find that cellular uptake increases with the number of DNG inserts, but only when these modifications are displayed on the outer surface of the SNA architecture. Furthermore, receptor blocking experiments indicate that uptake depends not only on scavenger receptor interactions but also on broader cell membrane composition. These findings demonstrate that both structural design and chemical composition can be tuned to control SNA uptake, underscoring the promise of structural nanomedicine for directing SNA‐cell interactions and rationally designing next‐generation nanotherapeutics. 

Proteins can template the heterogeneous nucleation and growth of size-confined nanocrystals. However, protein-templated mineralization often leads to particles that exhibit low colloidal stability, poor crystal quality, and/or diminished photoluminescence. Here, we report protein cage–spherical nucleic acids (SNAs) that can be used as nanoreactors for quantum dot (QD) synthesis and subsequent intracellular delivery. The resulting QD-SNA structures are monodisperse, colloidally stable, and photoluminescent in aqueous solution. The nanoreactors were prepared using two different proteins (~10 and 12 nanometers in diameter), and CdS, CdSe, and PbSe nanocrystals were synthesized. Moreover, the extent of surface defects and crystallinity depends on the relative concentrations of ionic precursors, which control the growth rate and the number of ionic vacancies. By optimizing conditions, CdS-SNAs that exhibit near-zero reabsorption loss were synthesized. Last, QD-SNAs exhibit enhanced cellular uptake and minimal cytotoxicity when compared to commercial QD-protein conjugates, making them potentially useful in bioimaging and diagnostic applications.