Adenosine Triphosphatases ; chemistry ; Antineoplastic Agents ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; Drug Screening Assays, Antitumor ; Female ; Humans ; Liver Neoplasms ; pathology ; Luminescence ; Luminescent Measurements ; Male ; Middle Aged ; Tumor Cells, Cultured

Immunoassays greatly contribute to veterinary drug residue analysis. However, there are few reports on detecting neomycin residues by immunoassay. Here, a rapid and sensitive chemiluminescent enzyme immunoassay (CLIEA) was successfully developed for neomycin residue analysis. CLIEA demonstrated good cross-reactivity for neomycin, and the IC50 value was 2.4 ng/mL in buffer. The average recovery range was 88.5%-105.4% for spiked samples (10, 50, and 100 μg/kg), and the coefficient of variation was in the range of 7.5%-14.5%. The limit of detection of CLEIA was 9.4 μg/kg, and this method was compared with the liquid chromatography-tandem mass spectrometry method using naturally contaminated samples, producing a correlation coefficient of >0.95. We demonstrate a reliable CLIEA for the rapid screening of neomycin in milk.
Animals ; Anti-Bacterial Agents ; metabolism ; Drug Residues ; metabolism ; Food Contamination ; analysis ; Immunoenzyme Techniques ; veterinary ; Limit of Detection ; Luminescent Measurements ; veterinary ; Milk ; chemistry ; Neomycin ; metabolism

AIMTo establish a new and simple flow injection method for the rapid determination of acetylspiramycin (ASPM).

METHODSASPM was determined by chemiluminescence (CL) method combined with flow injection (FI) technology, which was based on the inhibitive effect of ASPM on the chemiluminescence reaction of the luminol-K3Fe (CN)6 system.

RESULTSThe decrease of chemiluminescence intensity was proportional to the logarithm of ASPM concentration (0.1-100) microgram.L-1, the detection limit was 40 ng.L-1 (3 sigma). The whole process, including sampling and washing, could be completed in 0.5 min with a RSD less than 3.0% (n = 5).

CONCLUSIONThe FI-CL method is of both high sensitivity and good selectivity giving a throughput of 120 h-1. The proposed method was applied successfully to the determination of ASPM in pharmaceutical preparations and human urine without any pre-treatment. It was found that the ASPM concentration reached its maximum after being orally administrated for two hours.

Anti-Bacterial Agents ; analysis ; blood ; urine ; Flow Injection Analysis ; Humans ; Luminescent Measurements ; Luminol ; chemistry ; Male ; Microchemistry ; Spiramycin ; analogs & derivatives ; analysis ; blood ; urine

Various Leishmania species were engineered with green fluorescent protein (GFP) using episomal vectors that encoded an antibiotic resistance gene, such as aminoglycoside geneticin sulphate (G418). Most reports of GFP-Leishmania have used the flagellated extracellular promastigote, the stage of parasite detected in the midgut of the sandfly vector; fewer studies have been performed with amastigotes, the stage of parasite detected in mammals. In this study, comparisons were made regarding the efficiency for in vitro G418 selection of GFP-Leishmania amazonensis promastigotes and amastigotes and the use of in vivo G418 selection. The GFP-promastigotes retained episomal plasmid for a prolonged period and G418 treatment was necessary and efficient for in vitro selection. In contrast, GFP-amastigotes showed low retention of the episomal plasmid in the absence of G418 selection and low sensitivity to antibiotics in vitro. The use of protocols for G418 selection using infected BALB/c mice also indicated low sensitivity to antibiotics against amastigotes in cutaneous lesions.
Amebicides/*pharmacology ; Animals ; Flow Cytometry ; Gentamicins/*pharmacology ; Green Fluorescent Proteins/*chemistry ; Host-Parasite Interactions ; Leishmania mexicana/drug effects/genetics/*growth & development ; Leishmaniasis, Cutaneous/*parasitology ; Luminescent Agents/*chemistry ; Macrophages, Peritoneal/parasitology ; Mice ; Mice, Inbred BALB C ; Organisms, Genetically Modified ; Spectrometry, Fluorescence