Antiproliferative drug-loaded multi-functionalized intraocular lens for reducing posterior capsular opacification

Preparation and Application of Hemostatic Hydrogels

Hemorrhage remains a critical challenge in various medical settings, necessitating the development of advanced hemostatic materials. Hemostatic hydrogels have emerged as promising solutions to address uncontrolled bleeding due to their unique properties, including biocompatibility, tunable physical characteristics, and exceptional hemostatic capabilities. In this review, a comprehensive overview of the preparation and biomedical applications of hemostatic hydrogels is provided. Particularly, hemostatic hydrogels with various materials and forms are introduced. Additionally, the applications of hemostatic hydrogels in trauma management, surgical procedures, wound care, etc. are summarized. Finally, the limitations and future prospects of hemostatic hydrogels are discussed and evaluated. This review aims to highlight the biomedical applications of hydrogels in hemorrhage management and offer insights into the development of clinically relevant hemostatic materials.

Self-assembled coating with a metal-polyphenolic network for intraocular lens modification to prevent posterior capsule opacification

Posterior capsule opacification (PCO) is a main complication after cataract surgery and intraocular lens (IOLs) implantation and is attributed to residual lens epithelial cells (LECs) migrating to the IOL surface and posterior capsules. IOL surface modification has been a newly-developing research filed in recent years; however, the applicability and economical acquisition of modified materials remain unsolved. In this study, we first applied a metal-polyphenolic network coating with a self-assembly technique on the IOL surface by using tannic acid (TA) combined with AlCl3, which are easily acquire and applying on the IOL surface to solve the IOL transmittance affair. Using wound healing and Transwell assay to verify AZD0364 inhibits cell migration (P< 0.05), the lipopolysaccharide-induced macrophage inflammation model to verify pterostilbene (PTE) inhibits the inflammatory reaction (P< 0.01). By optimizes its self-assembly coating parameters and calculating its drug release kinetics, we successfully loaded these two drugs on the coating, named TA (AZD0364/PTE) IOL. Its surface morphology characteristics were analyzed by scanning electron microscope, x-ray photoelectron spectrometer and water contact angle. The optical performance was carefully investigated by optical instruments and equipment (n= 3). Thein vitroresults showed that TA (AZD0364/PTE) IOL can significantly inhibit cell adhesion and acute inflammation (n= 3,P< 0.0001). Importantly, afterin vivoimplantation for 28 d with eight rabbits PCO models in two groups, the TA (AZD0364/PTE) IOL group maintained clear refracting media and decreased the inflammatory reaction compared with the original IOL group (P< 0.05). This study provides a new applicable and economical strategy for preventing PCO and offers a reference for the next generation of IOLs that benefit cataract patients.

Innovation in the Development of Synthetic and Natural Ocular Drug Delivery Systems for Eye Diseases Treatment: Focusing on Drug-Loaded Ocular Inserts, Contacts, and Intraocular Lenses

Nowadays, ocular drug delivery still remains a challenge, since the conventional dosage forms used for anterior and posterior ocular disease treatments, such as topical, systemic, and intraocular administration methods, present important limitations mainly related to the anatomical complexity of the eye. In particular, the blood-ocular barrier along with the corneal barrier, ocular surface, and lacrimal fluid secretion reduce the availability of the administered active compounds and their efficacy. These limitations have increased the need to develop safe and effective ocular delivery systems able to sustain the drug release in the interested ocular segment over time. In the last few years, thanks to the innovations in the materials and technologies employed, different ocular drug delivery systems have been developed. Therefore, this review aims to summarize the synthetic and natural drug-loaded ocular inserts, contacts, and intraocular lenses that have been recently developed, emphasizing the characteristics that make them promising for future ocular clinical applications.

Quartz Crystal Microbalance-Based Aptasensors for Medical Diagnosis

Aptamers are important materials for the specific determination of different disease-related biomarkers. Several methods have been enhanced to transform selected target molecule-specific aptamer bindings into measurable signals. A number of specific aptamer-based biosensors have been designed for potential applications in clinical diagnostics. Various methods in combination with a wide variety of nano-scale materials have been employed to develop aptamer-based biosensors to further increase sensitivity and detection limit for related target molecules. In this critical review, we highlight the advantages of aptamers as biorecognition elements in biosensors for target biomolecules. In recent years, it has been demonstrated that electrode material plays an important role in obtaining quick, label-free, simple, stable, and sensitive detection in biological analysis using piezoelectric devices. For this reason, we review the recent progress in growth of aptamer-based QCM biosensors for medical diagnoses, including virus, bacteria, cell, protein, and disease biomarker detection.

Rapid and Economical Drug-Eluting IOL Preparation via Thermoresponsive Agarose Coating for Effective Posterior Capsular Opacification Prevention

Posterior capsular opacification (PCO), the highest incidence complication after cataract surgery, is mainly due to the attachment, proliferation, and migration of the residual lens epithelial cells (LECs). Although the drug-eluting IOLs have been proved to be an effective way to prevent PCO incidence, its preparations are time consuming and require tedious preparation steps. Herein, the thermoreversible agarose is adopted to prepare drug-eluting IOL. Such functional coating can be obtained easily by simple immersion in the antiproliferative drug containing hot agarose and taken out for cooling, which not only does not affect the optical property but also can effectively decrease the PCO incidence after intraocular implantation. As a result, the proposed agarose coating provides a rapid and economical alternative of drug-eluting IOL fabrication for PCO prevention.

Recent Advances of Intraocular Lens Materials and Surface Modification in Cataract Surgery

Advances in cataract surgery have increased the demand for intraocular lens (IOL) materials. At present, the progress of IOL materials mainly contains further improving biocompatibility, providing better visual quality and adjustable ability, reducing surgical incision, as well as dealing with complications such as posterior capsular opacification (PCO) and ophthalmitis. The purpose of this review is to describe the research progress of relevant IOL materials classified according to different clinical purposes. The innovation of IOL materials is often based on the common IOL materials on the market, such as silicon and acrylate. Special properties and functions are obtained by adding extra polymers or surface modification. Most of these studies have not yet been commercialized, which requires a large number of clinical trials. But they provide valuable thoughts for the optimization of the IOL function.

Research Progress Concerning a Novel Intraocular Lens for the Prevention of Posterior Capsular Opacification

Posterior capsular opacification (PCO) is the most common complication resulting from cataract surgery and limits the long-term postoperative visual outcome. Using Nd:YAG laser-assisted posterior capsulotomy for the clinical treatment of symptomatic PCO increases the risks of complications, such as glaucoma, retinal diseases, uveitis, and intraocular lens (IOL) pitting. Therefore, finding how to prevent PCO development is the subject of active investigations. As a replacement organ, the IOL is implanted into the lens capsule after cataract surgery, but it is also associated with the occurrence of PCO. Using IOL as a medium for PCO prophylaxis is a more facile and efficient method that has demonstrated various clinical application prospects. Thus, scientists have conducted a lot of research on new intraocular lens fabrication methods, such as optimizing IOL materials and design, and IOL surface modification (including plasma/ultraviolet/ozone treatment, chemical grafting, drug loading, coating modification, and layer-by-layer self-assembly methods). This paper summarizes the research progress for different types of intraocular lenses prepared by different surface modifications, including anti-biofouling IOLs, enhanced-adhesion IOLs, micro-patterned IOLs, photothermal IOLs, photodynamic IOLs, and drug-loading IOLs. These modified intraocular lenses inhibit PCO development by reducing the residual intraoperative lens epithelial cells or by regulating the cellular behavior of lens epithelial cells. In the future, more works are needed to improve the biosecurity and therapeutic efficacy of these modified IOLs.

Surface Self-Assembly Construction of Therapeutic Contact Lens with Bacterial "Kill-Releasing" and Drug-Reloading Capabilities for Efficient Bacterial Keratitis Treatment

Bacterial keratitis, an ophthalmic emergency, can cause corneal perforation and even endophthalmitis, thus leading to severe visual impairment. To achieve effective treatment of bacterial keratitis, good bioavailability of antimicrobial drugs on the ocular surface is desired. In this investigation, a layer-by-layer (LBL) self-assembly combined with the host-guest recognition was used to construct an antibacterial coating on the surface of corneal contact lens (CLs) to improve drug bioavailability and achieve successful treatment of bacterial keratitis. First, a radical copolymerization of acrylic acid (AA) and 1-adamantan-1-ylmethyl acrylate (AdA) was carried out to synthesize a polyanionic copolymer P(AA-co-AdA) (defined as PAcA). Then, PAcA copolymer combined with poly(ethyleneimine) (PEI) was used for a layer-by-layer (LBL) self-assembly to fabricate multilayer films on the surface of CLs. An antibacterial conjugate, β-cyclodextrin-levofloxacin (β-CD-LEV), was successfully synthesized and utilized to generate antibacterial coating through a host-guest interaction between AdA and β-CD-LEV. The antibacterial ability and treatment effect of bacterial keratitis was evaluated by in vitro assay and in vivo test in an animal model of staphylococcal keratitis, demonstrating that the antibacterial coating had good antibacterial and germicidal efficacy both in vivo and in vitro. We believe that this work will provide a promising strategy for the treatment of bacterial keratitis.

Uniform Mass Sensitivity Distribution of Elliptically Designed Electrodes Based on a Quartz Crystal Microbalance

Uniformization of mass sensitivity distribution is conducive to the application of the quartz crystal microbalance (QCM) in some fields. However, the sensitivity of the QCM sensor surface perpendicular to the displacement direction is higher that of the displacement direction in the mass sensitivity distribution of ring and double-ring QCMs, which leads to poor reproducibility of the sensor. Considering the effect of the electrode structure on the mass sensitivity distribution, we found that for ring- and double-ring-type QCMs, when the elliptical single ring and double-ring electrode structures are combined, an approximately uniform mass sensitivity can be obtained in all directions. Therefore, this study proposes the elliptical single-ring and elliptical double-ring electrode structure design. Through theoretical calculations and three-dimensional finite element analysis verification, a systematic investigation is carried out to quantify the effect of the ratio of the minor axis to the major axis of the elliptical electrode on the mass sensitivity distribution in different directions, and the optimal ratio is found to be 0.8. Comparing the mass sensitivity of the new type of electrodes and the original electrodes, the result shows that the mass sensitivity distribution of the elliptical double-ring electrode structure is more uniform. Hence, these specially designed electrodes are conducive to improving the repeatability.

Preparation of 5-fluorouracil loaded chitosan microtube via in situ precipitation for glaucoma drainage device application: in vitro and in vivo investigation

The main reason for the failure of glaucoma drainage devices is the chronic inflammatory reaction caused by the poor biocompatibility of biomaterials, which leads to the migration and proliferation of scleral fibroblasts surrounding the devices thus forming the encapsulation that will block the aqueous humor drainage channel. In order to inhibit the reaction of scleral fibroblasts after glaucoma drainage device implantation, this study designed and fabricated a 5-fluorouracil (5-FU) loaded chitosan microtube (CMT) for glaucoma aqueous humor drainage. The CMTs were made by template based adsorption-precipitation method using chitosan with excellent biocompatibility as raw material due to its characteristic of pH dependent solubility. The physical properties of CMTs were investigated. The in vitro and in vivo biocompatibilities were studied as well. The developed drainage device is expected to possess the dual function of reducing intraocular pressure and inhibiting excessive fibrosis after glaucoma drainage device implantation, thereby providing a novel way for the research of glaucoma drainage devices.

Drug-Eluting Hydrophilic Coating Modification of Intraocular Lens via Facile Dopamine Self-Polymerization for Posterior Capsular Opacification Prevention

Posterior capsular opacification (PCO) is the most important complication in cataract phacoemulsification and intraocular lens (IOL) implantation surgery, mainly stemming from the adhesion, proliferation, and transdifferentiation of the postsurgically residual lens epithelial cells (LECs). Previous investigations mainly focused on the hydrophilic surface modification of the IOLs for PCO prevention, such as heparinization. However, the long-term clinical investigations show that there is no significant difference between pristine and heparinized IOLs. In the present study, a synergetic coating with properties of drug-eluting and hydrophilicity was designed and modified onto the IOL surface via facile dopamine self-polymerization. The antiproliferative drug doxorubicin (DOX) was loaded when a polydopamine (PDA) coating was formed on the IOL surface. The hydrophilic 2-methacryloyloxyethyl phosphorylcholine (MPC) could be subsequently grafted onto the drug-loaded PDA coating surface easily. The hydrophilic outer layer could slow down drug-eluting from underneath the drug-incorporated coating. In vitro and in vivo investigations demonstrated that such multifunctionalized coating-modified IOLs could not only thoroughly and effectively prevent PCO development by induced cell apoptosis but also render safety and biocompatibility to the surrounding tissues.

Facile multifunctional IOL surface modification via poly(PEGMA-co-GMA) grafting for posterior capsular opacification inhibition

Posterior capsule opacification (PCO) is a significant complication of intraocular lens (IOL) implantation in cataract surgery, in which the adhesion and proliferation of lens epithelial cells (LECs) on the implanted IOL surface play an important role. The surface modification of IOL to prevent LEC adhesion and proliferation is a practical way to reduce the incidence of PCO. In this study, a multifunctional binary copolymer of poly(ethylene glycol) methacrylate (PEGMA) and glycidyl methacrylate (GMA) was synthesized (poly(PEGMA-co-GMA), PPG) and chemically grafted onto the aminolyzed IOL surface, utilizing the coupling reaction of epoxy and amino groups. Doxorubicin (DOX) was subsequently immobilized on the surface coating via the reaction of epoxy and amino groups as well. Taking advantages of the hydrophilicity of the PEG segments in the copolymer coating and the anti-proliferative effects of the DOX, a multifunctional surface coating was easily established by the synthesized copolymer PPG. Such anti-proliferative drug immobilized hydrophilic coating modification may effectively reduce the cell adhesion and proliferation and thus it is hypothesized to have great potential in PCO inhibition. The synthesis of PPG was confirmed by proton nuclear magnetic resonance spectroscopy (¹H-NMR) and Fourier transform infrared spectroscopy (FTIR). The surface coating immobilization was demonstrated by X-ray photoelectron spectroscopy (XPS). The in vitro drug release profiles and the cell behaviors were also investigated to validate the multifunctional coating inhibition effect on cellular adhesion and antiproliferation. Finally, the in vivo ocular implantation was carried out on rabbit eyes to evaluate the effect of the coating modified IOL on the inhibition of postoperative PCO. It followed that such multifunctional coating modification can effectively inhibit the adhesion and proliferation of LECs and significantly reduce the incidence of PCO. All these results reveal that such PPG copolymer modification provides a facile yet effective way to inhibit PCO formation after IOL implantation.

Drug eluting and hydrophilic intraocular lens surface coating was facilely fabricated via poly(PEGMA-co-GMA) grafting. Such a multifunctional coating reduced posterior capsular opacification incidence after implantation effectively.