Pharmacokinetics and biodistribution of amikacin encapsulated in carrier erythrocytes.
OBJECTIVE
To study the changes in the pharmacokinetics and tissue distribution of the aminoglycoside amikacin in rats using amikacin carrier erythrocytes as a delivery system.


METHODS
Amikacin-loaded erythrocytes were obtained using a hypotonic dialysis method. The pharmacokinetic and tissue distribution of amikacin were studied in three groups of rats receiving intravenous amikacin in saline solution, amikacin-loaded erythrocytes and amikacin-loaded erythrocytes treated with glutaraldehyde. Pharmacokinetic analysis was accomplished using model-independent methods.


RESULTS
Administration of the antibiotic using carrier erythrocytes elicited a sustained release effect, with an increase in the plasma half-life and in the area under the curve of the antibiotic. The tissue pharmacokinetics of amikacin using carrier erythrocytes in comparison with a control group revealed an accumulation of the antibiotic in specific tissues such as the liver and spleen, a similar pharmacokinetics in the lung and moderate changes in the pharmacokinetics in the kidney. Studies of tissue concentrations after the injection of glutaraldehyde-treated loaded erythrocytes demonstrated important changes in organs of the reticulo-endothelial system (RES) in comparison with the results observed for standard carrier erythrocytes, higher levels being observed in the liver whereas spleen levels decreased.


CONCLUSIONS
The administration of amikacin in loaded erythrocytes in rats leads to significant changes in the pharmacokinetic behaviour of the antibiotic, a greater accumulation being observed in RES organs such as liver and spleen. This shows that loaded erythrocytes are potentially useful for the delivery of antibiotics in phagocytic cells located in the RES.
Gutiérrez Millán
Carmen
C
Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Salamanca, Salamanca, Spain.
Zarzuelo Castañeda
Aránzazu
A
González López
Francisco
F
Sayalero Marinero
María Luisa
ML
Lanao
José M
JM
D000583:Amikacin / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics*; D000818:Animals; D004337:Drug Carriers / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics*; D004339:Drug Compounding / Q000379:methods; D004912:Erythrocytes / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution / Q000187:drug effects / Q000502:physiology
D004337:Drug Carriers; D000583:Amikacin