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Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds
Published on: September 8, 2021
Daptomycin eluted from calcium sulfate appears effective against Staphylococcus.
Nathan D Webb1, Jonathan D McCanless, Harry S Courtney
1University of Memphis, Memphis, TN, USA. nwebb1@memphis.edu
Clinical Orthopaedics and Related Research
|April 24, 2008
Summary
Daptomycin antibiotic eluted from calcium sulfate pellets maintained its effectiveness against Gram-positive bacteria, offering a potential new treatment for osteomyelitis.
Area of Science:
- Orthopedics
- Infectious Diseases
- Biomaterials
Background:
- Osteomyelitis treatment is challenged by resistant Gram-positive bacteria.
- Daptomycin shows promise but is underutilized for osteomyelitis.
- Local drug delivery vehicles are needed for osteomyelitis therapy.
Purpose of the Study:
- To evaluate daptomycin's retained activity when eluted from calcium sulfate.
- To assess calcium sulfate as a local delivery vehicle for daptomycin in osteomyelitis treatment.
Main Methods:
- Daptomycin was mixed with calcium sulfate hemihydrate (lab powder and commercial kit).
- Hardened pellets were formed and daptomycin elution was measured.
- Bacterial growth inhibition assays were performed using Staphylococcus aureus and Staphylococcus epidermidis.
Main Results:
- Daptomycin eluted from calcium sulfate retained its inhibitory activity against Gram-positive bacteria.
- Activity was observed for eluates collected up to 28 days post-pellet formation.
- Sterilized daptomycin-calcium sulfate pellets demonstrated sustained antibacterial effects.
Conclusions:
- Calcium sulfate is a viable local delivery vehicle for daptomycin in osteomyelitis.
- Daptomycin eluted from calcium sulfate maintains antibacterial activity against key Gram-positive pathogens.
- This combination presents a promising therapeutic strategy for resistant osteomyelitis infections.
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