| Abstract: | Despite many advances in catheter design and use, the most common cause of hospital-acquired infections is catheterization of the urinary tract. In the present investigation the adherence of bacteria to catheters coated with heparin was studied. Since heparin itself does not coat the plastic catheter surface, a complex of heparin with tridodecylmethylammonium chloride (TDMAC) was used which results in hydrophobic association of hydrocarbon chains of the TDMAC with the catheter leaving the quaternary ammonium moiety of TDMAC exposed to the surface forming ionic bonds with the highly anionic sulfate groups of heparin. Coating latex catheter material with TDMAC without heparin resulted in 3.6-fold higher adherence whereas coating with the TDMAC-heparin complex reduced adherence to less than 10% of control untreated latex. TDMAC-heparin also significantly reduced bacterial adherence to teflon coated latex (Bardex) and vinyl catheter material. Less than 30% of the original heparin was removed after wash periods of up to one week. These results indicate that TDMAC-heparin coating of urethral catheters reduces bacterial adherence and thereby may delay the acquisition of catheter associated urinary tract infection. |
