Syntheses of Platinum-Sulindac Complexes and Their Nanoparticles as Targeted Anticancer Drugs.

Platinum(II)-sulindac complexes [{η2 -C5 H4 SN(O)}Pt(DMSO){O(C=O)Sulindac}], [{η2 -C5 H4 SN(O)}PtCl{(S=O)Sulindac}], [{η2 -C5 H4 SN(O)}PtCl{(S=O)Sulindac-succinimide}], and [{η2 -C5 H4 SN(O)}PtCl{(S=O)Sulindac-thymidine}] were synthesized that exhibited IC50 values of 2.9-4.8 µm against human oral cancer cells OECM1. The poly(lactic-co-glycolic acid) (PLGA) encapsulated [{η2 -C5 H4 SN(O)}PtCl{(S=O)Sulindac}] also showed cytotoxic activity although less potent than the pristine species.

Elastic and Self-Healing Copolymer Coatings with Antimicrobial Function.

The revolutionary self-healing function for long-term and safe service processes has inspired researchers to implement them in various fields, including in the application of antimicrobial protective coatings. Despite the great advances that have been made in the field of fabricating self-healing and antimicrobial polymers, their poor transparency and the trade-off between the mechanical and self-healing properties limit the utility of the materials as transparent antimicrobial protective coatings for wearable optical and display devices. Considering the compatibility in the blending process, our group proposed a self-healing, self-cross-linkable poly{(n-butyl acrylate)-co-[N-(hydroxymethyl)acrylamide]} copolymer (AP)-based protective coating combined with two types of commercial cationic antimicrobial agents (i.e., dimethyl octadecyl (3-trimethoxysilylpropyl) ammonium chloride (DTSACL) and chlorhexidine gluconate (CHG)), leading to the fabrication of a multifunctional modified compound film of (AP/b%CHG)-grafted-a%DTSACL. The first highlight of this research is that the reactivity of the hydroxyl group in the N-(hydroxymethyl)acrylamide of the copolymer side chains under thermal conditions facilitates the "grafting to" process with the trimethoxysilane groups of DTSACL to form AP-grafted-DTSACL, yielding favorable thermal stability, improvement in hydrophobicity, and enhancement of mechanical strength. Second, we highlight that the addition of CHG can generate covalent and noncovalent interactions in a complex manner between the two biguanide groups of CHG with the AP and DTSACL via a thermal-triggered cross-linking reaction. The noncovalent interactions synergistically serve as diverse dynamic hydrogen bonds, leading to complete healing upon scratches and even showing over 80% self-healing efficiency on full-cut, while covalent bonding can effectively improve elasticity and mechanical strength. The soft nature of CHG also takes part in improving the self-healing of the copolymer. Moreover, it was discovered that the addition of CHG can enhance antimicrobial effectiveness, as demonstrated by the long-term superior antibacterial activity (100%) against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria and the antifouling function on a glass substrate and/or a silica wafer coated by the modified polymer.

The down regulation of target genes by photo activated DNA nanoscissors.

An artificial, targeted, light-activated nanoscissor (ATLANS) was developed for precision photonic cleavage of DNA at selectable target sequences. The ATLANS is comprised of nanoparticle core and a monolayer of hydrazone-modified triplex-forming oligonucleotides (TFOs), which recognize and capture the targeted DNA duplex. Upon photo-illumination (lambda = 460 nm), the attached hydrazone scissor specifically cleaves the targeted DNA at a pre-designed nucleotide pair. Electrophoretic mobility shift and co-precipitation assays revealed sequence-specific binding with the short-fragment and long-form plasmid DNA of both TFO and TFO-nanoparticle probes. Upon photo-illumination, ATLANS introduced a precise double-stranded break 12bp downstream the TFO binding sequence and down-regulated the target gene in HeLa cell system. Gold nanoparticles multiplexed the cutting efficiency and potential for simultaneous manipulation of multiple targets, as well as protected DNA from non-specific photo-damage. This photon-mediated DNA manipulation technology will facilitate high spatial and temporal precision in simultaneous silencing at the genome level, and advanced simultaneous manipulation of multiple targeted genes.