BACKGROUND AND PURPOSE: Antibiotic-releasing bioresorbable implants are used for local treatment of bone infections, but most drug delivery systems release antibiotic for too short a time. METHODS: We used pellets (0.9 x 1.0 mm) made of bioabsorbable poly(DL) lactic acid matrix, ciprofloxacin (7.3 +/- 0.4 wt%), and bioactive glass microspheres of 90-125 microm (29.3 +/- 0.2 wt%). The ciprofloxacin release and antibacterial activity was measured in elution tests in vitro and local tissue concentrations were measured in rabbits. RESULTS: In elution tests in vitro, the therapeutic level (> 2 microg/mL) of ciprofloxacin was achieved within 6 h of the start of the test, and it was maintained for up to 300 days. The antibacterial activity of the antibiotic released from sterilized composites was similar to that of the unprocessed ciprofloxacin. In vivo measurements showed high local tissue concentrations (16-86 micrg/g of bone tissue) for 3 months. Compared to previous experiments on two-component polymeric matrices (PLGA or PDLLA) with ciprofloxacin alone, adding bioactive glass microspheres into the composite resulted in morphological changes that facilitated fluid intrusion into the microstructure and quickened ciprofloxacin release. INTERPRETATION: This type of composition of implant may fulfill the requirements of bone infection therapy, for sustained local release of the selected antibiotic over several months.
BACKGROUND AND PURPOSE: Antibiotic-releasing bioresorbable implants are used for local treatment of bone infections, but most drug delivery systems release antibiotic for too short a time. METHODS: We used pellets (0.9 x 1.0 mm) made of bioabsorbable poly(DL) lactic acid matrix, ciprofloxacin (7.3 +/- 0.4 wt%), and bioactive glass microspheres of 90-125 microm (29.3 +/- 0.2 wt%). The ciprofloxacin release and antibacterial activity was measured in elution tests in vitro and local tissue concentrations were measured in rabbits. RESULTS: In elution tests in vitro, the therapeutic level (> 2 microg/mL) of ciprofloxacin was achieved within 6 h of the start of the test, and it was maintained for up to 300 days. The antibacterial activity of the antibiotic released from sterilized composites was similar to that of the unprocessed ciprofloxacin. In vivo measurements showed high local tissue concentrations (16-86 micrg/g of bone tissue) for 3 months. Compared to previous experiments on two-component polymeric matrices (PLGA or PDLLA) with ciprofloxacin alone, adding bioactive glass microspheres into the composite resulted in morphological changes that facilitated fluid intrusion into the microstructure and quickened ciprofloxacin release. INTERPRETATION: This type of composition of implant may fulfill the requirements of bone infection therapy, for sustained local release of the selected antibiotic over several months.
Authors: Amanda E Brooks; Benjamin D Brooks; Sherry N Davidoff; Paul C Hogrebe; Mark A Fisher; David W Grainger Journal: Drug Deliv Transl Res Date: 2013-12 Impact factor: 4.617
Authors: Niina Ahola; Minna Veiranto; Noora Männistö; Matti Karp; Jaana Rich; Alexander Efimov; Jukka Seppälä; Minna Kellomäki Journal: Biomatter Date: 2012 Oct-Dec
Authors: Niina Ahola; Noora Männistö; Minna Veiranto; Matti Karp; Jaana Rich; Alexander Efimov; Jukka Seppälä; Minna Kellomäki Journal: Biomatter Date: 2013-01-01
Authors: Sharad P Parwe; Priti N Chaudhari; Kavita K Mohite; Balaji S Selukar; Smita S Nande; Baijayantimala Garnaik Journal: Int J Nanomedicine Date: 2014-03-26