t of acetaminophen nanoparticles on liver toxicity in a rat model Original Research (6408) Total Article Views Authors: Esmaeil Biazar, S Mahdi Rezayat, Naser Montazeri, et al Published Date March 2010 Volume 2010:5 Pages 197 - 201 DOI: http://dx.doi.org/10.2147/IJN.S5894 Esmaeil Biazar1, S Mahdi Rezayat2, Naser Montazeri1, Khalil Pourshamsian1, Reza Zeinali3, Azadeh Asefnejad3, Mehdi Rahimi3, Mohammadmajid Zadehzare3, Mehran Mahmoudi3, Rohollah Mazinani3, Mehdi Ziaei3 1Department of Chemistry, Islamic Azad University, Tonekabon Branch, Mazandaran, Iran; 2Department of Pharmacology, School of Medicine, Tehran University of Medical Science, Tehran, Iran; 3Biomedical Engineering, Islamic Azad University, Research and Science Branch, Tehran, Iran Abstract: Acetaminophen, a pain-reliever, is one of the most widely used medications in the world. Acetaminophen with normal dosage is considered a nontoxic drug for therapeutic applications, but when taken at overdose levels it produces liver damage in human and various animal species. By a high energy mechanically activated method, we produced acetaminophen in a nanometer crystalline size (24 nm). Forty-eight hours after injection of crystalline particles with normal and reduced size of our drug, the effect of liver toxicity was compared by determination of liver transferase enzymes such as alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase (ALT). These enzymes were examined by routine colorimetric methods using commercial kits and pathologic investigations. Statistical analysis and pathological figures indicated that ALT delivery and toxicity in reduced size acetaminophen was significantly reduced when compared with normal size acetaminophen. Pathology figures exhibited reduced necrosis effects, especially the confluent necrosis, in the central part of the lobule in the reduced size acetaminophen samples when compared with the normal samples.