Properties of erythromycin‐loaded polymeric dicalcium phosphate dehydrate bone graft substitute

Abstract

A self-setting, injectable polymeric dicalcium phosphate dehydrate bone graft substitute that is mechanically strong and has excellent cohesion was developed.We assessed the performance of erythromycin-loaded polymeric dicalcium phosphate dehydrate cement. Its properties include drug release, growth inhibition against Staphylococcus aureus and biocompatibility with osteoblastic MC3T3 cells.The impact of erythromycin loading on cement injectability, setting time, and mechanical strength were also evaluated. A sustained, low burst release of erythromycin was observed. Eluents collected from erythromycin-loaded cement showed a considerable zone of inhibition for up to 28 days. Direct contact of erythromycin-loaded cement discs with agar plate showed a similarly sizable zone of inhibition for up to 22 days. Degraded ceramic residues had strong zones of inhibition as well. While the erythromycin-loaded cement was injectable, a notable delay of the setting time was observed (49.2 ± 6.8 min) as compared with control (drug-free cement, 12.2 ± 2.6 min). A slight increase in compressive strength (60.83 ± 6.28 MPa) was observed in erythromycin-loaded cement as compared with control (59.41 ± 6.48 MPa). Erythromycin-loaded cement was biocompatible although reduced cell growth was observed in the presence of the cement eluent.We propose that the bactericidal efficacy of erythromycin-loaded cement was caused by the combined effects of erythromycin released and exposed on the contact surface of degrading ceramics. Our data may elucidate the future application of polymeric dicalcium phosphate dehydrate bone graft substitute for the treatment of orthopedic infections and opportunities to use other antibiotics and applications considering its comparable handling and mechanical strength to poly (methyl methacrylate) cements.

Osteoblastic differentiation and bactericidal activity are enhanced by erythromycin released from PCL/PLGA-PVA coaxial nanofibers

“…The released EM concentrations were measured using a method we have previously described. 28 A mixture of 0.1 mL eluent with 0.1 mL of 3 m sulfuric acid was heated at 50°C for 30 min. The absorbance was recorded using a UV/VIS Spectrophotometer (Synergy HT; BioTek Instruments) at a wavelength of 485 nm ( n = 3 per group).…”

A slow and sustained release of methotrexate (MTX) from a new polymeric dicalcium phosphate dehydrate cement (P-DCPD)

“…plays a critical role in the mechanical performance of P-DCPD. For example, loading of erythromycin 28 and/or tobramycin 27 at high concentration (10% wt/wt) had little impacts on the mechanical performance of P-DCPD. Doxorubicin is one of the effective and broad spectrum anticancer drugs.…”

“…25 To the best of our knowledge, no ceramic cement using similar technologies has been reported before. P-DCPD represents a new bone void filler with significant advantages, including strong mechanically strength, 26 excellent cohesion, 24 as well as a mean of sustained drug delivery 27,28 because of its unique ionic binding and intrinsic entanglement of polyphosphate chains with embedded drugs. 29 The handling properties of P-DCPD is similar to PMMA cement and other commercially available CPCs.…”

Repair of a rat calvaria defect with injectable strontium (Sr)‐doped polyphosphate dicalcium phosphate dehydrate (P‐DCPD) ceramic bone grafts

“…12 The compressive strength of the material tested without any drug ranged between 60 and 70 MPA. 12 P-DCPD represents a promising means of tailoring drug delivery, in particular, antibiotics, 15,16 due to its ionic binding and intrinsic disentangled polyphosphate chains. 15 Strontium (Sr), a minor element, is found naturally in human bodies and in our diets.…”

“…12 P-DCPD represents a promising means of tailoring drug delivery, in particular, antibiotics, 15,16 due to its ionic binding and intrinsic disentangled polyphosphate chains. 15 Strontium (Sr), a minor element, is found naturally in human bodies and in our diets. 17 Sr has a long history of use in health supplements or toothpastes to strengthen bones and teeth.…”