Polymer nanomaterials for use as adjuvant surgical tools

Abstract

Materials employed in the treatment of conditions encountered in surgical and clinical practice frequently face barriers in translation to application. Shortcomings can be generalized through their reduced mechanical stability, difficulty in handling, and inability to conform or adhere to complex tissue surfaces. To overcome an amalgam of challenges, research has sought the utilization of polymer-derived nanomaterials deposited in various fashions and formulations to improve the application and outcomes of surgical and clinical interventions. Clinically prevalent applications include topical wound dressings, tissue adhesives, surgical sealants, hemostats, and adhesion barriers, all of which have displayed the potential to act as superior alternatives to current materials used in surgical procedures. In this review, emphasis will be placed not only on applications, but also on various design strategies employed in fabrication. This review is designed to provide a broad and thought-provoking understanding of nanomaterials as adjuvant tools for the assisted treatment of pathologies prevalent in surgery. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Implantable Materials and Surgical Technologies > Nanoscale Tools and Techniques in Surgery.

Keywords: adhesion barrier; hemostat; surgical sealant; tissue adhesive; wound dressing.

Figure 1:

Schematic of intended function, metrics for clinical assessment, and failure modes for materials deployed in surgery. (a) Wound dressings often encounter minimal shrinkage of damaged tissue as quantified via epidermal wound closure. (b) Tissue adhesives fail due to a combination of bulk and interfacial modes as assessed via adhesion strength. (c) Surgical sealants are ineffective if low burst pressure values are presented in sealing of a defect. (d) Hemostats have limited utility if long clotting times and significant blood loss is encountered. (e) Adhesion barrier failure leads to post-operative scar tissue formation that can be quantified via a scoring rubric.

Figure 2:

Schematic of application approaches for nanomaterials used in surgery. (a) Solution blow spinning employs pressure driven flow through a nozzle to generate a collection of fibers with nanoscale diameter and porosity. (b) Electrospinning utilizes a high voltage current and conductive substrate to deposit a nanofiber mat onto a collector and harvested for application to tissue. (c) Hydrogels are synthesized through either combination of a monomer solution with crosslinking agents and initiators or a standalone, neat polymer solution. Injectable hydrogels are ones that display shear thinning behavior and can be injected through a syringe (left). Non-injectable solutions are either mixed in an attached tip of a dual-barrel syringe (middle) or are mixed as bulk solutions in a mold (right) that are then formed for specific application.