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:

Oily nanosuspension for long-acting intramuscular delivery of curcumin didecanoate prodrug: Preparation, characterization and in vivo evaluation. The objective of this study was to prepare the nanocrystals of curcumin didecanoate (CurDD) by wet ball milling and to investigate the comparative pharmacokinetics of oily nano- and micro-suspensions after intramuscular (i.m.) administration to rats. Upon optimizing the wet ball milling parameters, CurDD nanocrystals were produced with median particle size of ∼500nm and the freeze-dried nanocrystals were readily dispersed in peanut oil to form stable nanosuspensions. Although the nanosuspension appeared to exhibit slower clearance from the injection site after i.m. injection, compared to microsuspension (∼5μm), a significantly higher maximum plasma curcumin concentration (69.0ng/ml) was observed for the former than that for the latter (18.5ng/ml). In addition, the nanosuspension provided significant higher plasma curcumin concentrations and brain CurDD contents for at least 15days than the microsuspension, except for the initial times. A single i.m. injection of nanosuspension appeared to achieve reversal effect on reserpine-induced hypothermia for at least 13days. This study demonstrates that CurDD nanosuspension may act as a long-acting i.m. injectable for sustained delivery of curcumin, potentially applicable to elicit a long-lasting antidepressant effect.
{"Chemical": ["curcumin", "curcumin didecanoate", "CurDD", "reserpine"]}