A multi-signal fluorescent probe, represented by:

##STR00001##

A method for preparing the multi-signal fluorescent probe includes: (a) adding 2-methoxyphenothiazine and ethyl iodide into a mixture of dichloromethane (DCM) and acetonitrile followed by a first reaction and a first post-treatment to obtain 10-ethyl-2-methoxy-10H-phenothiazine; (b) adding boron tribromide into the 10-ethyl-2-methoxy-10H-phenothiazine under an inert gas followed by a second reaction under an ice bath and a second post-treatment to obtain 10-ethyl-10H-phenothiazin-2-ol; and (c) mixing the 10-ethyl-10H-phenothiazin-2-ol, malonic acid, zinc chloride and phosphorus oxychloride followed by a third reaction and a third post-treatment to obtain the multi-signal fluorescent probe. A use of the multi-signal fluorescent probe in the detection of intracellular ONOO.sup.- and Na.sub.2S.sub.2 is also provided.

The instant invention provides near-infrared fluorescent biological contrast agents and methods of using them.

Herein described are solid oral compositions of dyes for use in diagnostic endoscopy, preferably colon endoscopy.

The present invention discloses a preparation technique of composite nanodots based on carbon nanodots, and their use in the field of fluorescent imaging, wherein, the main components of the composition are carbon nanodots, which are material with superior biocompatibility characteristics, and supporting component is methylene blue, and particle diameter range is 100-500 nanometers, and the zeta potential is −35 to 10 millivolts. The above said techniques for preparation of composite nanodots are safe, quick and simple, low cost, and easy to perform for industrialized production. Composite carbon nanodots have good biocompatibility and safety, high fluorescence imaging sensitivity, and they are promising in gaining wider use in the fields of biomedical imaging, targeting diagnosis and therapy, drug screening and optimization, and in vivo labelling and tracing, and have potential value in personalized medicine.

Disclosed are a film-forming agent composition for contrast agent, a film-forming lipid solution including the film-forming agent composition, a contrast agent including the film-forming lipid solution, and a preparation method thereof. The film-forming agent composition for contrast agent includes a lipid, an emulsifier and a surface charge modifier; relative to 100 parts by weight of the lipid, the content of the emulsifier is 20-50 parts by weight, and the content of the surface charge modifier is 10-35 parts by weight; and the lipid is a carboxylated phospholipid, and the surface charge modifier is a polyelectrolyte. Based on the composition, the nanodroplets of the resulting contrast agent have more uniform particle size, higher stability and better controllability, as well as a lower threshold value for ultrasonic gasification.

Provided herein is a drug delivery (DD) system for ratiometric luminescence determination of drug release degree in drug delivery monitoring, which includes a drug, a switchable reporter and non-switchable reporter providing two distinguishable signals for detection; or a single switchable reporter providing two distinguishable signals for detection, and a cleavable linker connecting a drug to a switchable reporter, as well as a method for ratiometric luminescence determination of drug release in a target (in vivo or in vitro), which is effected by administering the DD system provided herein that is capable of releasing a drug from the DD system, measuring two luminescent signals provided by the switchable reporter and the non-switchable reporter, or the single switchable reporter, determining the ratio between these two luminescence signals, and determining the drug release degree through the ratio between the two luminescence signals.

Methods for detecting the presence of atherosclerotic structures in order to diagnose or prevent atherosclerosis are provided herein. In particular, it has been found that methylene blue injected intravenously acts as an excellent indicator because the compound targets high-risk plaque, atheroma, macrophages, and other atherosclerotic structures formed within the endothelial walls of a vessel of a subject. Because the compound provides a unique binding profile with uptake only in plaque or atheroma, and not the normal or healthy vascular interstitial tissue, methylene blue maintains a good plaque-to-background ratio for imaging purposes. This enables healthcare providers to determine the status of atherosclerosis development in vivo within a patient with higher certainty and at lower costs. The disclosed methods allow for high-resolution mapping of plaque build-up, plaque pathobiology, and other atherosclerotic structures within a vessel of a subject by using methylene blue as an imaging agent.

The present invention relates to the field of medicine, specifically to ophthalmic surgery, more specifically to an improved staining composition for ophthalmic surgery with low toxicity and increased staining efficiency.

The instant invention provides near-infrared fluorescent biological contrast agents and methods of using them.

The instant invention provides near-infrared fluorescent nerve contrast agents and methods of using them.