Influence of a new surface modification of intraocular lenses with fluoroalkylsilan on the adherence of endophthalmitis-causing bacteria in vitro.
BACKGROUND
Dynasilan is a fluoroalkylsilan that is able to interact with surface active centres on intraocular lenses (IOL), offering a new way for surface modification of different IOL materials. The purpose of this in vitro study was to investigate the influence of this new surface modification on the adherence of two typical endophthalmitis causing bacteria (Staphylococcus epidermidis, Propionibacterium acnes).


METHODS
In a pilot experiment, the effect of Dynasilan coating on the adherence of S. epidermidis was tested on glass slides. Forty-two Dynasilan-modified and 42 unmodified IOL (14 PMMA, 14 silicone and 14 hydrogel) were incubated at 37 degrees C in brain heart infusion broth (10(8) CFU/ml) with either S. epidermidis for 24 h or with P. acnes for 1 h. Subsequently, the adherent bacteria were resuspended using ultrasonification at 35 kHz for 3x45 s. After dilution series and incubation at 37 degrees C on Petri dishes for 24 h and 3 days, respectively, the colonies were counted.


RESULTS
In the pilot experiment, a markedly lower number of adherent S. epidermidis was observed on Dynasilan-modified glass slides. Of all IOL materials incubated with S. epidermidis, those modified with Dynasilan showed a lower mean number of adherent bacteria (mean 1.37x10(7); SD 2.37x10(7)) than those untreated (2.43x10(7); SD 3.04x10(7)). IOLs incubated with P. acnes showed a significantly lower mean number of adherent bacteria of 2.51x10(4) (SD 2.71x10(4)) on Dynasilan-modified IOLs versus 6.27x10(4) (SD 7.70x10(4)) on untreated IOLs.


CONCLUSIONS
The presented in vitro results indicate that Dynasilan surface modification is able to reduce the adherence of S. epidermidis and P. acnes on all IOL materials tested. Further studies regarding the stability of this modification and its biocompatibility must be performed.
Kienast
Antonia
A
University Eye Clinic Lübeck, Lübeck, Germany.
Kämmerer
Regine
R
Weiss
Claudia
C
Klinger
Matthias
M
Menz
Dirk-Henning
DH
Dresp
Joachim
J
Ohgke
Helge
H
Solbach
Werner
W
Laqua
Horst
H
Hoerauf
Hans
H
D001422:Bacterial Adhesion / Q000502:physiology*; D020099:Coated Materials, Biocompatible; D015169:Colony Count, Microbial; D009877:Endophthalmitis / Q000382:microbiology*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007910:Lenses, Intraocular / Q000382:microbiology*; D008855:Microscopy, Electron, Scanning; D019904:Polymethyl Methacrylate; D011425:Propionibacterium acnes / Q000502:physiology*; D012821:Silanes; D012826:Silicone Elastomers; D013212:Staphylococcus epidermidis / Q000502:physiology*; D005466:Fluorocarbons
D020099:Coated Materials, Biocompatible; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D019904:Polymethyl Methacrylate; D012821:Silanes; D012826:Silicone Elastomers; C516498:3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilan; D005466:Fluorocarbons