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.

Described herein are processes and compositions for ultrasound-triggered liposome payload release, including a process for gelation and a process for enzyme catalysis.

One aspect of the invention provides a method for freeze-drying surfactant-stabilized microbubbles. The method includes: preparing vials comprising a mixture comprising microbubbles; partially submerging the vials in a chilled water bath, wherein the water bath has a sub-freezing temperature; placing the vials on a cooled shelf of a lyophilizer; freeze-drying the vials in the lyophilizer; and capping the freeze-dried vials. Another aspect of the invention provides a method for annealing surfactant-stabilized microbubbles. The method includes: preparing vials comprising a mixture comprising microbubbles; passing the vials in and out of liquid nitrogen (LN.sub.2) until the mixture is frozen; holding the vials at −20° C.; placing the vials on a cooled shelf of a lyophilizer; freeze-drying the vials in the lyophilizer; and capping the freeze-dried vials.

Provided herein are improved methods for preparing phospholipid formulations including phospholipid UCA formulations.

Provided herein are improved methods for preparing phospholipid formulations including phospholipid UCA formulations.

Provided herein are improved methods for preparing phospholipid formulations including phospholipid UCA formulations.

Methods and devices for producing a population of liposomes are provided. Aspects of the methods include applying a centrifugal force to a suspension of liposomes in a manner sufficient to pass the liposomes through a porous membrane to produce a population of liposomes. Aspects of the invention further include devices, systems and kits useful for performing the methods.

Provided herein are improved methods for preparing phospholipid formulations including phospholipid UCA formulations.

Provided herein are improved methods for preparing phospholipid formulations including phospholipid UCA formulations.

The present disclosure provides imaging agents that are useful for the detection and evaluation of heart conditions, such as myocardial infarction. Upon activation, the imaging agents of the present disclosure may be detected using an ultrasound imaging device.