Long acting anti-infection constructs on titanium

Abstract

Peri-prosthetic joint infections (PJI) are a serious adverse event following joint replacement surgeries; antibiotics are usually added to bone cement to prevent infection offset. For uncemented prosthesis, alternative antimicrobial approaches are necessary in order to prevent PJI; however, despite elution of drug from the surface of the device being shown one of the most promising approach, no effective antimicrobial eluting uncemented device is currently available on the market. Consequently, there is a clinical need for non-antibiotic antimicrobial uncemented prosthesis as these devices present numerous benefits, particularly for young patients, over cemented artificial joints. Moreover, non-antibiotic approaches are driven by the need to address the growing threat posed by antibiotic resistance.We developed a multilayers functional coating on titanium surfaces releasing chlorhexidine, a wellknown antimicrobial agent used in mouthwash products and antiseptic creams, embedding the drug between alginate and poly-beta-amino-esters.Chlorhexidine release was sustained for almost 2 months and the material efficacy and safety was proven both in vitro and in vivo. The coatings did not negatively impact osteoblast and fibroblast cells growth and were capable of reducing bacterial load and accelerating wound healing in an excisional wound model.As PJI can develop weeks and months after the initial surgery, these materials could provide a viable solution to prevent infections after arthroplasty in uncemented prosthetic devices and, simultaneously, help the fight against antibiotic resistance.

Molecular Sizes and Antibacterial Performance Relationships of Flexible Ionic Liquid Derivatives

“…53 Bacterial infection and suppuration formation were disadvantageous to the blood flow, and inhibited the normal delivery of nutrients to the wound areas. 54 As shown in Figure 7c, the infected wounds treated by ILD-6 and ILD-12 had better blood flow than ILD-8, demonstrating the better therapeutic effect of ILD-6 and ILD-12. The wound tissues of the rats at Day 7 were harvested and sliced for H&E staining to assess the anti-infection abilities of ILDs against PAO1 (Figure 7d).…”

“…To further evaluate the therapeutic effect of ILDs, laser Doppler flowmetry was used to measure the cutaneous blood flow under the wound area during healing . Bacterial infection and suppuration formation were disadvantageous to the blood flow, and inhibited the normal delivery of nutrients to the wound areas . As shown in Figure c, the infected wounds treated by ILD-6 and ILD-12 had better blood flow than ILD-8, demonstrating the better therapeutic effect of ILD-6 and ILD-12.…”

Regenerative Activities of ROS-Modulating Trace Metals in Subcutaneously Implanted Biodegradable Cryogel

“…Adipose tissue ( Figure 8 , 3 ) detected as hollow reticular areas (corresponding to washed-out lipid contents of adipocytes) [ 41 ] was also enlarged and deeply penetrated into the dermis in the presence of Zn and Cu components, respectively, by ca. 1.5 times (day 5) and over 1.7 times (day 10), compared to the control (non-doped cryogel).…”

Amplify Antimicrobial Photo Dynamic Therapy Efficacy With Poly-beta-amino Esters (PBAEs)

“…PBAE were rst described as biodegradable polymers that could be potential gene transfer vectors in light of their positive charges and ability to form complexes with DNA molecules 46 ; subsequent evidence has validated such properties and identi ed key features and optimised the polymer chain backbone in order to maximise the opportunities offered by such polymers to transfer genes into target cells 47,48 . Further applications of PBAEs have been proposed for cancer drug delivery [49][50][51][52] , in layer-by-layer deposition of drug releasing coatings 38,[53][54][55][56][57][58] and drug localisation in cartilage 31,32 . Depending on the application, different PBAE features have been shown to pivot the outcome; for example PBAEs belonging to the family of B3 and A16 are known cell uptake enhancer in DNA delivery [46][47][48] while A5 and B5 are better at driving drug uptake into cartilage 32 ; additionally it has also been proven that end-capping has a further critical role 32,47 .…”