Ice Confinement Enabled Click Conjugation of DNA Oligonucleotides and Macromolecules

DNA bioconjugates integrate the programmable recognition and structural precision of nucleic acids with the diverse properties of (bio)polymers, enabling functional architectures across sensing, biomedicine, and nanotechnology. While versatile conjugation chemistry (e.g., click reaction) is available, linking DNA oligonucleotides with synthetic polymers and biomacromolecules is hampered by steric shielding and length-dependent masking of reactive sites. Here, we report a facile freezing strategy that exploits ice confinement to drive highly efficient, template-free coupling of DNA oligonucleotides with diverse (bio)polymers. Our freezing strategy enables near-quantitative (>90%) coupling of oligonucleotides with synthetic polymers (polyethylene glycol) and biopolymers (bovine serum albumin and anti-PD-L1) with preserved cell targeting/uptake capability. Moreover, the accelerated template-free ligation allows us to obtain ssDNA with architectures previously challenging, such as long strands (>150 nt), strands with inverted orientations (5′–5′, 3′–3′), and branched structures. By unifying multiple conjugation chemistries under biocompatible, low-temperature conditions, our results establish freezing as a general strategy for constructing DNA-(bio)polymer conjugates, with broad implications for analytical chemistry, chemical biology, nanotechnology, and precision medicine.