In vitro antibacterial efficacy of tetracycline hydrochloride adsorbed onto Bio‐Oss® bone graft

Abstract

Local delivery of antibiotics may provide the advantage of reducing the potential side effects associated with their systemic administration. This study assessed, in vitro, the antimicrobial efficacy of tetracycline hydrochloride (TCH) adsorbed onto Bio-Oss bone grafts against a range of pathogenic bacteria. Various levels of TCH were adsorbed onto Bio-Oss granules by immersing in TCH aqueous solutions of different initial concentrations for 48 h at room temperature. TCH release was assessed in phosphate buffered saline at 37 degrees C, and its antimicrobial efficacy, up to 96 h, was tested against two Gram-negative bacteria associated with periodontal diseases: Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, and Porphyromonas gingivalis, and one Gram-positive bacterium associated with soft-tissue and bone infections: Staphylococcus aureus. The range of TCH concentrations studied was also assessed for cytotoxicity against osteoblast-like human osteosarcoma cell lines. The amount of TCH adsorbed and released from Bio-Oss was concentration dependent. All TCH adsorbed Bio-Oss resulted in a reduction of A. actinomycetemcomitans, P. gingivalis, and S. aureus and higher concentrations were generally more effective in reducing or eliminating bacterial growth. The proliferation of HOS cells was not substantially reduced except for the maximum concentration of TCH. In addition to its osteoconductive role, TCH adsorbed Bio-Oss could also be functional in negating systemically antibiotic prophylactic treatment in the prevention of implant or biomaterial related infections.

Evaluation of antibacterial and cytotoxic effects of nano-sized bioactive glass/collagen composites releasing tetracycline hydrochloride

“…In the study carried out by Dashti et al . (), 0·01 mg ml −1 of TCH was well tolerated by HOS human osteosarcoma cell line. Higher concentrations (0·1 and 1 mg ml −1 ) resulted in the inhibition of cell proliferation.…”

“…This behaviour is in line with Dashti et al . () who reported no statistical differences in Staph. aureus NCTC6571 cell growth inhibition when TCH concentrations were in the range of 0·015–0·065 mg ml −1 .…”

“…Mechanistically, the antibiotic binds with hydroxyapatite by forming complexes with calcium ions (Misra ; Dashti et al . ).…”

pH-controlled delivery of gentamicin sulfate from orthopedic devices preventing nosocomial infections

“…Most of them are based on the biodegradability of biomaterial in which the drugs are dissolved [52,53] and consequently released continuously. Non-biodegradable materials for which the active molecule is dissolved or adsorbed are also used and the drug released is based on diffusion or desorption phenomena [54,55]. In all these cases, the high initial release rate and the prolonged deliverance (few weeks after the surgery) are possible but do not permit a treatment for delayed infection.…”

Characterization, drug loading and antibacterial activity of nanohydroxyapatite/polycaprolactone (nHA/PCL) electrospun membrane

“…0.2% TCH is suitable for cell growth since a higher concentration of TCH can be toxic to cells. TCH at a concentration of 0.01 and 0.1 mg/ml is considered good for cell proliferation, and a higher concentration may inhibit the cells' growth (Dashti et al 2010). The addition of TCH does not affect the morphology of the nanofibers and the water contact angle reduced.…”