[Acute pulmonary toxicity of rats caused by different sized SiO2 nanoparticles].

Objective: To study the pulmonary toxicity to rats induced by different sized SiOz particles.

Methods: One hundred and five male SD rats were divided into seven groups randomly according to their weight. Experimental rats were exposed to 20, 50, 80, 140, 280 and 800 nm SiO2 particles at the dose of 400 mg/m3 by inhalation for 2 hours respectively.

Quantification of cholesterol in foods using non-aqueous capillary electrophoresis.

A simple method for the rapid quantification of cholesterol in egg yolk and milk by non-aqueous capillary electrophoresis (NACE) is described in this paper. The samples were treated with saponification and then quantified by NACE, in which 100 mM sodium acetate-acetic acid in methanol was employed as the running buffer. The correlation coefficient between the cholesterol concentration and the corresponding peak area was 0.