Injectable Functional Biomaterials for Minimally Invasive Surgery

Abstract

Injectable materials represent very attractive ready‐to‐use biomaterials for application in minimally invasive surgical procedures. It is shown that this approach to treat, for example, vertebral fracture, craniofacial defects, or tumor resection has significant clinical potential in the biomedical field. In the last four decades, calcium phosphate cements have been widely used as injectable materials for orthopedic surgery due to their excellent properties in terms of biocompatibility and osteoconductivity. However, few clinical studies have demonstrated certain weaknesses of these cements, which include high viscosity, long degradation time, and difficulties being manipulated. To overcome these limitations, the use of sol‐gel technology has been investigated, which has shown good results for synthesis of injectable calcium phosphate‐based materials. In the last few decades, injectable hydrogels have gained increasing attention owing to their structural similarities with the extracellular matrix, easy process conditions, and potential applications in minimally invasive surgery. However, the need to protect cells during injection leads to the development of double network injectable hydrogels that are capable of being cross‐linked in situ. This review will provide the current state of the art and recent advances in the field of injectable biomaterials for minimally invasive surgery.

Preparation of Single, Heteromorphic Microspheres, and Their Progress for Medical Applications

“…Therefore, microsphere is a superb material with great potential in the field of hemostasis in vitro. [ 124,125 ]…”

Recent Advances in Injectable Hydrogels for Controlled and Local Drug Delivery

“…This property is also crucial for more precise implantation and site-specific drug delivery into poorly reachable tissue sites and interface tissues, where wound healing takes a long time. Injectable hydrogels [8] can be generated in situ by using chemically and/or physically crosslinking hydrogels; thus they can be delivered into the body or a targeted site of a tissue through a catheter or by a syringe. Injectable hydrogels are particularly attractive biomaterials for use in soft tissues such as the brain and spinal cord, [9,10] since they have viscoelastic and unique rheological properties that can mimic the mechanical characteristics of soft tissues.…”

Structure–property relations in linear viscoelasticity of supramolecular hydrogels

“…[1][2][3] Owing to the transient nature of physical bonds between chains (that associate and dissociate being driven by external stimuli), these gels demonstrate high strength, 4 exceptional stretchability, 5 high fracture toughness 6 and fatigue resistance, 7 and rapid self-recovery. 8 Among other important features of supramolecular gels, it is worth mentioning (i) their self-healing ability, 9,10 (ii) shape memory property, 11,12 (iii) self-assembling (the ability to undergo sol-gel-sol transitions driven by mechanical and chemical triggers), 13,14 and (iv) the ability to secure strong and robust adhesion to a variety of surfaces. [15][16][17] As the mechanical behavior of supramolecular gels is strongly affected by rearrangement (dissociation and re-association) of temporary bonds between chains, a number of studies analyzed the kinetics of this process by means of the standard rheological tests (shear oscillations in the frequency sweep mode).…”