A water transfer printing method for contact lenses surface 2D MXene modification to resist bacterial infection and inflammation.

Contact lenses (CLs) are prone to adhesion and invasion by pollutants and pathogenic bacteria, leading to infection and inflammatory diseases. However, the functionalization of CL (biological functions such as anti-fouling, antibacterial, and anti-inflammatory) and maintaining its transparency still face great challenges. In this work, as a member of the MXenes family, vanadium carbide (V2C) is modified onto CL via a water transfer printing method after the formation of a tightly arranged uniform film at the water surface under the action of the Marangoni effect. The coating interface is stable owing to the electrostatic forces. The V2C-modified CL (V2C@CL) maintains optical clarity while providing good biocompatibility, strong antioxidant properties, and anti-inflammatory activities. In vitro antibacterial experiments indicate that V2C@CL shows excellent performance in bacterial anti-adhesion, sterilization, and anti-biofilm formation. Last, V2C@CL displays notable advantages of bacteria elimination and inflammation removal in infectious keratitis treatment.

pH-Activatable Organic Nanoparticles for Efficient Low-Temperature Photothermal Therapy of Ocular Bacterial Infection.

Low-temperature photothermal therapy (PTT) systems constructed by integrating organic photothermal agents with other bactericidal components that initiate bacterial apoptosis at low hyperthermia possess a promising prospect. However, these multicomponent low-temperature PTT nanoplatforms have drawbacks in terms of the tedious construction process, suboptimal synergy effect of diverse antibacterial therapies, and high laser dose needed, compromising their biosafety in ocular bacterial infection treatment. Herein, a mild PTT nanotherapeutic platform is formulated via the self-assembly of a pH-responsive phenothiazinium dye. These organic nanoparticles with photothermal conversion efficiency up to 84.5% necessitate only an ultralow light dose of 36 J/cm2 to achieve efficient low-temperature photothermal bacterial inhibition at pH 5.5 under 650 nm laser irradiation. In addition, this intelligent mild photothermal nanoplatform undergoes negative to positive charge reversion in acid biofilms, exhibiting good penetration and highly efficient elimination of drug-resistant E. coli biofilms under photoirradiation. Further in vivo animal tests demonstrated efficient bacterial elimination and inflammatory mitigation as well as superior biocompatibility and biosafety of the photothermal nanoparticles in ocular bacterial infection treatment. Overall, this efficient single-component mild PTT system featuring simple construction processes holds great potential for wide application and clinical transformation.

Killing three birds with one stone: Near-infrared light triggered nitric oxide release for enhanced photodynamic and anti-inflammatory therapy in refractory keratitis.

Stubborn resistant bacteria, bacterial biofilms and severe inflammation are challenging issues in refractory keratitis treatment. Herein, we design a multifunctional near-infrared light-responsive nanoplatform for efficient therapy of refractory keratitis based on a "three-birds-with-one-stone" strategy, which integrates the bacteria targeting photodynamic therapy, nitric oxide (NO) sterilization, and NO-mediated anti-inflammatory property into one system. This nanoplatform (UCNANs) is constructed using the dual-emissive upconversion nanoparticles (UCNPs) as cores coated with mesoporous silica for the loading of photosensitizers with aggregation-induced emission (AIE) property and the grafting of NO donors and bacteria targeting molecules. Upon irradiation of 808 nm light, UCNPs simultaneously produce UV emission and visible emission to trigger NO release and reactive oxygen species (ROS) such as superoxide radical (O2•-) generation. Furthermore, O2•- resulting from PDT can react with NO to yield powerful oxidizing and nitrating agent peroxynitrite (ONOO-). The three components work synergistically to enhance the antibacterial outcome confirmed by in vitro and in vivo tests. The short-distance light excitation and excitation light absorption are important reasons for reducing the toxicity of materials, especially ultraviolet light damage. Moreover, bacteria elimination reduced endotoxin secretion and the released NO simultaneously inhibit the NF-κB pathways by regulating the expression of toll-like receptor 2 (TRL2) and tumor necrosis factor-α (TNF-α), which significantly relieves the inflammation of cornea. Given its excellent antibacterial and anti-inflammatory properties, UCNANs provides a competitive strategy for refractory keratitis therapy.

Drug-free contact lens based on quaternized chitosan and tannic acid for bacterial keratitis therapy and corneal repair.

Bacterial keratitis (BK) and related inflammatory diseases causes irreversible damage to the corneal tissue. In this study, a novel polyacrylamide semi-interpenetrating network hydrogel including quaternized chitosan and tannic acid (PAM-QCS-TA) were used to construct a novel antibacterial and antioxidant contact lens. The obtained hydrogels showed high water content (>85%), swelling resistance, light transmittance (>90%) and adjustable mechanical property. Both quantitative and qualitative antibacterial experiments against Staphylococcus aureus and Escherichia coli (E. coli) indicated excellent sterilization function especially against E. coli (almost 100%). Due to the presence of tannin acid, it showed obvious antioxidant properties, which relieved oxidative stress and protect cells from reactive oxygen species-induced cytotoxicity. Animal experiments also indicated the shortened treatment time of BK (only 3 days) as well as the protection of eye tissue structure. Therefore, such drug-free antibacterial and antioxidant contact lens avoiding the development of drug resistance is a potential candidate in ocular infectious and inflammatory diseases treatment.