Antifouling Polymeric coating for implantable cardiac devices

HridhayCoeur

Mechanical Heart Valve

• Preferred Prosthetic heart valve for 70,000 patients

• Approximately US$754.3 million of the healthcare market share

Drawbacks in Current Mechanical Heart Valve

Pannus Formation Dislocation of heart valves

Obstructive Thrombus formation

Drawbacks in Current Mechanical Heart Valve

Drawbacks in Current Mechanical Valves

Outcome Mechanical valve

Overall survival 43 %

Likelihood of structural failure Negligible

Likelihood of periprosthetic valve

leaks17 %

Risk of bleeding 42 %

Needs Statement

“To find a method to improve the biocompatibility of mechanical heart valve replacement devices, hence reducing the

post-operative complications”

Ultralow Fouling Polymers

Polymers containing acidic open ring structures such as Carboxylates or zwitterions

Ultralow fouling defined as less than 5 ng cm-2 of fibrinogen

adhesion onto surface

Attachment of these polymers can be through self assembly on the

substrate, plasma modification or using catechols.

Action of the polymer is by the resistance and repulsion of

proteins through the charge rich carboxylates or the zwitterions.

CB-OH

Modified from Manipulating Sticky and Non-Sticky Properties in a Single Material,Cao et al.,Smart Materials

Carboxylate ring with addition of –OH group to enhance the anti-fouling

effect

Stable in pH 7-pH 10 with optimal stability at pH7.6

• Single protein adhesion undetectable ( <0.3 ng cm-2)• Fibrinogen and Platelet adhesion is 3.1±1.0 ng cm-2

Zwitterionic effect enhances anti-fouling by repelling

other micro-organisms, cells and bacteria

Potential anti-thrombotic applications for implantable medical devices

Structure of polymer allows coating mechanisms such as

Atom transfer radical Polymerization or Plasma

deposition of polymer