Fixation of Transparent Bone Pins with Photocuring Biocomposites

Abstract

Bone fractures are in need of rapid fixation methods, but the current strategies are limited to metal pins and screws, which necessitate secondary surgeries upon removal. New techniques are sought to avoid surgical revisions, while maintaining or improving the fixation speed. Herein, a method of bone fixation is proposed with transparent biopolymers anchored in place via light-activated biocomposites based on expanding CaproGlu bioadhesives. The transparent biopolymers serve as a UV light guide for the activation of CaproGlu biocomposites, which results in evolution of molecular nitrogen (from diazirine photolysis), simultaneously expanding the covalently cross-linked matrix. Osseointegration additives of hydroxyapatite or Bioglass 45S5 yield a biocomposite matrix with increased stiffness and pullout strength. The structure−property relationships of UV joules dose, pin diameter, and biocomposite additives are assessed with respect to the apparent viscosity, shear modulus, spatiotemporal pin curing, and lap-shear adhesion. Finally, a model system is proposed based on ex vivo investigation with bone tissue for the exploration and optimization of UV-active transparent biopolymer fixation.

Color changing bioadhesive barrier for peripherally inserted central catheters

“…22,45 For example, modulus increases up to three-times with resorbable bioglass. 45 Zinc-containing bioglass would provide additional method of antibacterial protection. 47…”

“…CathoGlu is derived from previously reported carbene-based bioadhesives for fixation of soft tissues in vivo/ex vivo (iliac artery anastomosis). [22][23][24]45 The base consists of a hydrophobic, liquid polycaprolactone that allows dissolution of organic additives, 26,27 including the BTB pH indicator demonstrated herein. 22 In contrast to cyanoacrylate adhesives, CathoGlu is relatively soft and flexible.…”

“…If a stiffer modulus is required, additional organic 27 and inorganic additives are available to induce stiffer resins. 22,45 For example, modulus increases up to three-times with resorbable bioglass. 45 Zinc-containing bioglass would provide additional method of antibacterial protection.…”

“…22,45 For example, modulus increases up to three-times with resorbable bioglass. 45 Zinc-containing bioglass would provide additional method of antibacterial protection. 47 Other strategies are known for preventing catheter infections, but these rely on antibiotic impregnated adhesive films (BioPatch®, GuardIVa™) that may exacerbate resistance.…”

“…bioglass microparticles). 45 The standard E. coli cultures provide a fundamental information for assessment of barrier physical properties. Methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus are responsible for most blood stream infections related to catheter insertion.…”