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Self-protecting bactericidal titanium alloy surface formed by covalent bonding of daptomycin bisphosphonates.

ABSTRACT: Infections are a devastating complication of titanium alloy orthopedic implants. Current therapy includes antibiotic-impregnated bone cement and antibiotic-containing coatings. We hypothesized that daptomycin, a Gram-positive peptide antibiotic, could prevent bacterial colonization on titanium alloy surfaces if covalently bonded via a flexible, hydrophilic spacer. We designed and synthesized a series of daptomycin conjugates for bonding to the surface of 1.0 cm² Ti6Al4V foils through bisphosphonate groups, reaching a maximum yield of 180 pmol/cm². Daptomycin-bonded foils killed 53 ± 5% of a high challenge dose of 3 × 10? cfu Staphylococcus aureus ATCC 29213.

SUBMITTER: Chen CP

PROVIDER: S-EPMC2987735 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Self-protecting bactericidal titanium alloy surface formed by covalent bonding of daptomycin bisphosphonates.

Chen Chang-Po CP Wickstrom Eric E

Bioconjugate chemistry 20101015 11

Infections are a devastating complication of titanium alloy orthopedic implants. Current therapy includes antibiotic-impregnated bone cement and antibiotic-containing coatings. We hypothesized that daptomycin, a Gram-positive peptide antibiotic, could prevent bacterial colonization on titanium alloy surfaces if covalently bonded via a flexible, hydrophilic spacer. We designed and synthesized a series of daptomycin conjugates for bonding to the surface of 1.0 cm² Ti6Al4V foils through bisphosphon ...[more]

PMID: 20949909

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