Preparation and biodistribution of [131I]linezolid in animal model infection and inflammation

Linezolid is the first of new class of antibiotics, the oxazolidinones, and exhibits activity against many gram-positive organisms, including vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus, and penicillin-resistant Streptococcus pneumoniae. Aim of the study: Linezolid was to label with I-131 and potential of the radiolabeled antibiotic was to investigate in inflamed rats with S. aureus (S. aureus) and sterile inflamed rats with turpentine oil. Linezolid was labeled with I-131 by iodogen method. Biodistribution of [131I]linezolid was carried out in bacterial inflamed and sterile inflamed rats. Radiolabeling yield of [131I]linezolid was determined as 85 ± 1% at pH 2. After injecting of [131I]linezolid into bacterial inflamed and sterile inflamed rats, radiolabeled linezolid was rapidly removed from the circulation via the kidneys. Binding of [131I]linezolid to bacterial inflamed muscle (T/NT = 77.48 at 30 min) was five times higher than binding to sterile inflamed muscle (T/NT = 14.87 at 30 min) of rats. [131I]linezolid showed good localization in bacterial inflamed tissue. It was demonstrated that [131I]linezolid can be used to detect S. aureus inflammation in rats. (author)