Dynamic Nanostructures from DNA-Coupled Molecules, Polymers, and Nanoparticles.

Dynamic and reconfigurable systems that can sense and react to physical and chemical signals are ubiquitous in nature and are of great interest in diverse areas of science and technology. DNA is a powerful tool for fabricating such smart materials and devices due to its programmable and responsive molecular recognition properties. For the past couple of decades, DNA-based self-assembly is actively explored to fabricate various DNA-organic and DNA-inorganic hybrid nanostructures with high-precision structural control. Building upon past development, researchers have recently begun to design and assemble dynamic nanostructures that can undergo an on-demand transformation in the structure, properties, and motion in response to various external stimuli. In this Review, recent advances in dynamic DNA nanostructures, focusing on hybrid structures fabricated from DNA-conjugated molecules, polymers, and nanoparticles, are introduced, and their potential applications and future perspectives are discussed.

DNA-Grafted Poly(acrylic acid) for One-Step DNA Functionalization of Iron Oxide Nanoparticles.

Here, we report one-step DNA functionalization of hydrophobic iron oxide nanoparticles (IONPs) using DNA-grafted poly(acrylic acid) (PAA- g-DNA). PAA- g-DNA was synthesized by coupling PAA to amine-modified oligonucleotides via solid-phase amide chemistry, which yielded PAA grafted with multiple DNA strands with high graft efficiencies. Synthesized PAA- g-DNA was utilized as a phase-transfer and DNA functionalization agent for hydrophobic IONPs, taking advantage of unreacted carboxylic acid groups. The resulting DNA-modified IONPs were well dispersed in aqueous solutions and possessed DNA binding properties characteristic of polyvalent DNA nanostructures, showing that this approach provides a simple one-step method for DNA functionalization of hydrophobic IONPs.

Multimodal Shape Transformation of Dual-Responsive DNA Block Copolymers.

Herein, we report the self-assembly and multimodal shape transformation of dual-responsive DNA di- and triblock copolymers. Dual-responsive DNA diblock copolymer was synthesized by coupling a thermoresponsive polymer, poly(N-isopropylacrylamide (PNIPAM), and an oligonucleotide. DNA-b-PNIPAM possesses thermoresponsive properties of PNIPAM as well as molecular recognition properties of DNA. Thus, they undergo reversible temperature-triggered transition at lower critical solution temperature (LCST) between molecular DNA and polymer micelles with high density DNA corona. The hybridization of DNA-b-PNIPAM and DNA-modified nanoparticles generates functional nanoparticles showing unique temperature-dependent aggregation and disaggregation behaviors due to the dual-responsive nature of DNA-b-PNIPAM. DNA triblock copolymers of DNA-b-PNIPAM-b-PMA were synthesized by introducing a hydrophobic block, poly(methyl acrylate) (PMA), to DNA/PNIPAM block copolymers, which form spherical micelles at room temperature. They are capable of nanoscale shape transformation through the combination of thermal trigger and DNA binding. DNA-b-PNIPAM-b-PMA micelles undergo sphere-to-cylinder shape changes above LCST due to the conformational change of PNIPAM. The shape change is reversible, and fast cylinder-to-sphere transition occurs when the temperature is lowered below LCST. The low temperature spherical morphology can also be accessed while keeping the temperature above LCST by introducing complementary DNA strands with single stranded overhang regions. These results demonstrate the multidimensional shape changing capability of DNA-b-PNIPAM-b-PMA enabled by the dual-responsive property.

Impact of sleeve gastrectomy on the periodontal status of patients with and without type 2 diabetes: a 1-year prospective real-world study.

Background: Periodontitis is a chronic inflammatory disease potentially associated with obesity and type 2 diabetes (T2D). Sleeve gastrectomy (SG) has shown substantial effect on weight loss and treatment of T2D. However, there is no direct evidence comparing the impact of SG on the periodontal status of patients with and without T2D. Objectives: To determine the impact of SG on the periodontal status of patients with and without T2D in a real-world setting. Methods: In a prospective and two-armed cohort design, participants who were scheduled for SG at an affiliated hospital between April 2022 and December 2022 were approached for eligibility. After a clinical evaluation and oral examination, those with periodontitis were included and further divided into the DM group (diabetic) and the Control group (non-diabetic) with a 1-year follow-up after surgery. The primary outcome was the periodontal status of patients at 12 months after SG. The secondary outcomes included weight loss, diabetes remission, and alterations in inflammatory markers for up to 1 year after SG. Results: Fifty-seven and 49 patients were included in the DM and the Control group, respectively. Before surgery, patients in the DM group had further worsened periodontal condition compared with those in the Control group. Accompanied by weight loss and glucose reduction, patients in both groups demonstrated significant decreases in plaque index (PLI) and bleeding index (BI) with no alterations in probing depth or clinical attachment loss for up to 1 year after SG. Even patients in the DM group achieved less TWL% (32.79 ± 6.20% vs. 37.95 ± 8.34, P<0.01), their periodontal condition had more substantial improvement with no significant difference in PLI and BI between groups at 1 year after SG. We also observed a significant reduction in the levels of high sensitive C-reactive protein and interleukin-6 in both groups at 1 year after SG. Conclusion: Both patients with and without T2D demonstrated improved periodontal status for up to 1 year after SG. Patients with T2D achieved less weight loss but a more substantial improvement in periodontal condition. The significant reduction in inflammatory biomarkers contributed to the improvement of periodontal status after SG.

3D light-curing printing to construct versatile octopus-bionic patches.

Reliable, fast and switchable gluing modes are critically important in medical adhesives and intelligent climbing robot applications. The octopus-bionic patch has attracted the attention of many scholars. The suction cup structure of the octopus achieves adhesion through differential pressure, showing strong adhesion in both dry and wet environments. However, the construction of the octopus-bionic patch remains limited in terms of adaptability, personalization and mass production. Herein, a composite hydrogel consisting of gelatin methacryloyl (GelMA), polyethylene glycol diacrylate (PEGDA) and acrylamide (AAM) was developed, and a structure mimicking the octopus sucker was constructed by digital light processing (DLP). The obtained octopus-bionic patch has strong adhesion, good biocompatibility and multi-functionality. Compared with the template method in most studies, the octopus-bionic patch constructed by the DLP printing method has the advantages of customizability and low cost. In addition, the DLP printing method endows the patch surface with an octopus-like groove structure for a better bionic effect.

Peptide-Driven Shape Control of Low-Dimensional DNA Nanostructures.

We report the rational design and fabrication of unusual low-dimensional DNA nanostructures through programmable and sequence-specific peptide interactions. Dual-bioactive block copolymers composed of DNA and amino acid-based polymers (DNA-b-poly(amino acid)) were synthesized by coupling oligonucleotides to phenylalanine (Phe)-based polymers. Unlike prototypical DNA block copolymers, which typically form simple spherical micelles, DNA-b-poly(amino acid) assemble into various low-dimensional structures such as nanofibers, ribbons, and sheets through controllable amino acid interactions. Moreover, DNA-b-poly(amino acid) assemblies can undergo protease-induced fiber-to-sheet shape transformations, where the morphology change is dictated by the type of enzymes and amino acid sequences. The peptide-based self-assembly reported here provides a programmable approach to fabricate dynamic DNA assemblies with diverse and unusual low-dimensional structures.