3D Printed Hydrogels for Ocular Wound Healing

Abstract

Corneal disease is one of the most significant causes of blindness around the world. Presently, corneal transplantation is the only way to treat cornea blindness. It should be noted that the amount of cornea that people donate is so much less than that required (1:70). Therefore, scientists have tried to resolve this problem with tissue engineering and regenerative medicine. Fabricating cornea with traditional methods is difficult due to their unique properties, such as transparency and geometry. Bioprinting is a technology based on additive manufacturing that can use different biomaterials as bioink for tissue engineering, and the emergence of 3D bioprinting presents a clear possibility to overcome this problem. This new technology requires special materials for printing scaffolds with acceptable biocompatibility. Hydrogels have received significant attention in the past 50 years, and they have been distinguished from other materials because of their unique and outstanding properties. Therefore, hydrogels could be a good bioink for the bioprinting of different scaffolds for corneal tissue engineering. In this review, we discuss the use of different types of hydrogel for bioink for corneal tissue engineering and various methods that have been used for bioprinting. Furthermore, the properties of hydrogels and different types of hydrogels are described.

A novel wound dressing material for full-thickness skin defects composed of a crosslinked acellular swim bladder

“…Allogeneic skin-graft materials have been studied as another alternative (Łabuś et al, 2022), but they still face several drawbacks, such as immunological rejection and the potential spread of infectious diseases (Qiu et al, 2016). In addition, these materials are always associated with the disadvantage of poor mechanical strength, while high mechanical strength is an essential factor in constructing skin repair materials (Aghamirsalim et al, 2022). There is therefore a pressing need to prepare materials with excellent mechanical properties and biocompatibility comparable with those of human skin.…”

Hydrogels in Cutaneous Wound Healing: Insights into Characterization, Properties, Formulation and Therapeutic Potential

“…It can quickly lose its shape and stability due to enzymatic degradation [ 77 ]. Moreover, the long gelation time and low mechanical strength of printed collagen-based hydrogels pose additional challenges [ 78 , 79 ].…”

“…It is a highly porous, hydrophilic, moisture-permeable, biostable, highly biocompatible, biodegradable, and non-toxic polymer. Furthermore, it is widely recognized as safe, readily available in nature, inherently non-adhesive, easy to process, and possesses good resistance in acidic media [ 1 , 21 , 38 , 39 , 44 , 53 , 128 , 129 ] and transparency [ 78 , 92 ]. Moreover, alginate is renewable [ 130 , 131 ], has an eco-friendly nature [ 131 , 132 , 133 , 134 ], and is cost-effective [ 1 , 39 , 44 , 129 , 130 , 132 , 134 ].…”

Application Prospect and Preliminary Exploration of GelMA in Corneal Stroma Regeneration

“…In ophthalmology, corneal diseases, such as keratitis and corneal epithelial cell loss due to trauma, often result in a complete loss of transparency and function of the cornea, which ultimately ends in blindness. But corneal donors are again extremely scarce, and according to statistics, for every 70 patients worldwide who need a corneal transplantation, only one is able to obtain a corneal donor [ 12 ]. Therefore, scientists have been working to find an alternative to corneal donors, and keratocytes can grow stably in GelMA material with good transparency and stability.…”

“…Although these potential drawbacks of the use of human donor stromal tissue can be significant, the main drawback of stromal replacement with human donor tissue is the global shortage of donated corneas, especially in China [ 10 , 11 ]. According to the literature, for every 70 patients in the world who need a corneal transplant, only one is able to obtain a corneal donor [ 12 ]. The implantation of an allogenic corneal lenticule obtained by small-incision lenticule extraction (SMILE) can improve the visual acuity of patients by increasing the thickness of the corneal stroma, but it is also dependent on corneal donors and has great technical difficulties [ 13 , 14 ].…”