Slippery liquid infused fluoropolymer coating for central lines to reduce catheter associated clotting and infections

Abstract

Thrombosis and infections are two grave, interrelated problems associated with the use of central venous catheters (CVL). Currently used antibiotic coated CVL has limited clinical success in resisting blood stream infection and may increase the risk of emerging antibiotic resistant strains. We report an antibiotic-free, fluoropolymer-immobilized, liquid perfluorocarbon-coated peripherally inserted central catheter (PICC) line and its effectiveness in reducing catheter associated thrombosis and pathogen colonization, as an alternative to antibiotic coated CVL. Commercially available polyurethane PICC catheter was modified by a three-step lamination process, with thin fluoropolymer layers to yield fluoropolymer-polyurethane-fluoropolymer composite structure before applying the liquid perfluorocarbon (LP). This high throughput process of modifying commercial PICC catheters with fluoropolymer is quicker, safer and shows higher thromboresistance than fluorinated, omniphobic catheter surfaces, produced by previously reported self-assembled monolayer deposition techniques. The LP immobilized on the fluoropolymer is highly durable in physiological flow conditions for over 60 days and continue to resist Staphylococcus colonization.

Figure 1

Fluoropolymer laminated single lumen PICC catheter manufacturing process to obtain the three-layer PTFE–TPU–FEP structure.

Figure 2

Elemental composition of various pure fluoropolymer (FEP, PFA, PTFE, PVDF, ETFE) surfaces and F-SAM coated PICC.

Figure 3

Comparative picture (A) of thrombus covered BioFlo PICC, BARD PICC, LP/F-SAM PICC and FILP PICC after their exposure to 500 mL/min flow of sheep blood (heparin 1 IU /mL) for 4 h. Percentage of thrombus deposited area (B) on all four test samples. Activated clotting time and the quantified free floating clot at the end of the thrombogenicity test suggest no significant blood clotting happened during the 4 h period of blood circulation on FILP coated PICC.

Figure 4

Biofilm formation on BARD PICC and FILP PICC. (A, B) S. epi biofilm on BARD PICC. (C, D) S. aureus biofilm on BARD PICC. (E) S. epi single pathogen on FILP PICC. (F) S. aureus single pathogen on FILP. A comparison of quantified S. epi (G), S. aureus (H) biofilms in terms of viable cell count per cm (CFU/cm) of BARD PICC and FILP PICC. FILP PICC samples were isolated at various time points after exposing to physiological flow and the subsequent incubation with S. epi pathogen.

Figure 5

Comparison of surface roughness resulting from three different coating processes: F-SAM deposition on PICC under solution phase condition (A), CVD condition (C). Surface roughness (B) of FEP laminated PICC surface.