You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

A novel colloidal gold-based lateral flow immunoassay for rapid simultaneous detection of cyromazine and melamine in foods of animal origin. A rapid and sensitive lateral flow immunoassay (LFIA) based on competitive format was developed and validated for simultaneous detection of cyromazine (CA) and melamine (MA) in foods of animal origin. With this method, the cut-off value for the two test lines were achieved at 25 ng/g, which was lower than the maximum residue levels (MRLs) established for CA and MA. At three fortified levels (50, 100, and 150 ng/g), the recoveries for CA and MA ranged from 73.9% to 104.2% with the relative standard deviation (RSD) less than 11.9%, based on within day and interday analysis. The lower detection limit for CA and MA in matrix sample were 0.22 ng/ml and 0.26 ng/ml, respectively, which were lower than those of published literatures. A parallel analysis of CA and MA in real samples conducted by HPLC showed comparable results to those obtained from LFIA. The results of LFIA were in good agreement with those of high performance liquid chromatography (HPLC) in the analysis of CA and MA in foods of animal origin, demonstrating the practical applicability of the developed assay in real samples. Overall, to our knowledge, this is the first report of quantitative or semi-quantitative simultaneous detection for CA and MA by immunochromatographic assay.
{"Chemical": ["melamine", "cyromazine"]}