Gelatin Encapsulated Nitrogen Microbubbles as Ultrasonic Contrast Agents

Personalized nanomedicine advancements for stem cell tracking

“…For years, echogenic bubbles have been used as an ultrasonic contrast agent [230,231]. The second harmonic wave provided a background-free signal using an ultrasonic device[232].…”

Echocontrast enhancers — how safe are they?

“…Several investigators [28][29][30] have studied gelatin-encapsulated micro bubbles as potential ECAs, using a preparation from Rasor Associates (Sunnyvale, California), which was later withdrawn by the manufacturers. Meltzer et al [31] found commercially available gelatin to be a suitable medium for the generation of precision micro bubbles for experimental contrast echocardiographic use.…”

“…"Haemaccel" (Hoechst) is a gelatin-based solution, still commercially available in Europe, that is effective clinically as an echo contrast enhancer, giving contrast that lasts for as long as 60 seconds [33,34]. Unfortunately, mild transient sideeffects (transient second degree atrio-ventricular block, QRS axis deviation, transient T wave changes) were always present in a few patients, although the majority (21 of 25), experienced no significant electrocardiographic changes [30]. Berwing et al [35,36] tested a new ECM based on a commercially available agent, "Gelifundol" (Biotest Pharma ERG), consisting of 5.4% oxypolygelatin, widely used outside the USA as a plasma substitute.…”

Polymeric Microbubbles for Ultrasonic Molecular Imaging and Targeted Therapeutics

“…To improve microbubbles stability and optimizing diameter, researchers developed long-lived gas-filled microbubbles composed of stable membrane material like surfactant [6], albumin [5,7], galactose [8,9] and lipid [10,11]. The gas filled in microbubbles has advanced from air to CO 2 [12], N 2 [13] and to low-solubility gases such as SF 6 [14] and perfluorocarbon gases [15].…”