Reduction of Staphylococcus aureus and Pseudomonas aeruginosa colonisation on PVC through covalent surface attachment of fluorinated thiols.
OBJECTIVE
This study reports the development, characterisation and microbiological testing of surface-modified polyvinylchloride (PVC) films for the purpose of reducing bacterial adherence.


METHODS
Irreversible covalent surface modification was achieved via nucleophilic substitution of fluorinated thiol-terminated compounds onto the polymer backbone. Four fluorinated modifiers, 2,3,5,6-tetrafluorothiophenol (TFTP), 4-(trifluoromethyl)thiophenol (TFMTP), 3,5-bis(trifluoromethyl)benzenethiol (BTFMBT) and 3,3,4,4,5,5,6,6,7, 7,8,8,9,9,10,10,10-heptadecafluoro-decane-1-thiol (HDFDT), were investigated. Modification was confirmed using attenuated total reflectance infrared spectroscopy; Raman mapping demonstrated that modification was homogenous on the macroscopic scale. The influence of fluorination on surface hydrophobicity was studied by contact angle analysis. The effect on microbial adherence was examined using Pseudomonas aeruginosa and Staphylococcus aureus.


RESULTS
The resultant changes in contact angle relative to control PVC ranged from -4 degrees to +14 degrees . In all cases, adherence of P. aeruginosa and S. aureus was significantly reduced relative to control PVC, with adherence levels ranging from 62% and 51% for TFTP-modified PVC to 32% and 7% for TFMTP-modified PVC.


CONCLUSIONS
These results demonstrate an important method in reducing the incidence of bacterial infection in PVC medical devices without compromising mechanical properties.
McCoy
Colin P
CP
School of Pharmacy, Queen's University, 97 Lisburn Road, Belfast BT9 7BL, UK. c.mccoy@qub.ac.uk
Cowley
John F
JF
Gorman
Sean P
SP
Andrews
Gavin P
GP
Jones
David S
DS
D001422:Bacterial Adhesion / Q000187:drug effects*; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D011143:Polyvinyl Chloride / Q000737:chemistry*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development; D013059:Spectrum Analysis, Raman; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
D006845:Hydrocarbons, Fluorinated; D013438:Sulfhydryl Compounds; D011143:Polyvinyl Chloride