Hj. Griesser et al., Elimination of stick-slip of elastomeric sutures by radiofrequency glow discharge deposited coatings, J BIOMED MR, 53(3), 2000, pp. 235-243
Fine elastomeric sutures intended for cardiovascular surgery can exhibit "s
tick-slip" behavior as they are pulled through tissue; the resulting oscill
atory force can damage delicate tissue or cause sutures to snap. To elimina
te this undesirable effect, sutures were surface-modified using a radiofreq
uency glow discharge in a vapor of either hexamethyldisiloxane or hexamethy
ldisilazane, to produce a thin polymeric coating on the suture. The same co
atings were also deposited onto aluminized tape to facilitate their charact
erization by measurement of air/water contact angles and by X-ray photoelec
tron spectroscopy. Coatings from both monomers were found to be very hydrop
hobic, The hexamethyldisiloxane glow discharge coatings underwent negligibl
e oxidation when stored in air, and thus remained stable over a shelf-life
period akin to what may be required of sutures. The hexamethyldisilazane gl
ow discharge coatings, in contrast, incorporated substantial amounts of oxy
gen over a 3-month period. The coatings did not measurably alter the tensil
e properties of the sutures. The frictional properties of coated sutures we
re assessed by measuring the dynamic friction between the suture and ovine
myocardium. Both coatings were effective in removing the inherent stick-sli
p behavior of polybutester sutures in this model. The coatings remained int
act after several passes and proved to be robust and efficacious under vari
ous strain regimes. (C) 2000 John Wiley & Sons, Inc.