Spatially Specific Liposomal Cancer Therapy Triggered by Clinical External Sources of Energy

Abstract

This review explores the use of energy sources, including ultrasound, magnetic fields, and external beam radiation, to trigger the delivery of drugs from liposomes in a tumor in a spatially-specific manner. Each section explores the mechanism(s) of drug release that can be achieved using liposomes in conjunction with the external trigger. Subsequently, the treatment’s formulation factors are discussed, highlighting the parameters of both the therapy and the medical device. Additionally, the pre-clinical and clinical trials of each triggered release method are explored. Lastly, the advantages and disadvantages, as well as the feasibility and future outlook of each triggered release method, are discussed.

Using a Microfluidics System to Reproducibly Synthesize Protein Nanoparticles: Factors Contributing to Size, Homogeneity, and Stability

“…NP colloidal systems can, thus, be used to avoid the problems associated with formulation vehicles, in addition to protecting the drug from premature degradation [5]. While stable drug plasma levels can be achieved through the gradual release of the drug from its carrier, burst doses of the drug can also be delivered to specific locations using external triggers, such as ultrasound or ionizing radiation [6,7]. Although NPs are promising for drug delivery in medical applications, issues such as their limited drug encapsulation efficiency, biocompatibility, and colloidal stability have thus far prevented their widespread use in the clinic [8].…”

Enhanced Radiosensitization for Cancer Treatment with Gold Nanoparticles through Sonoporation

“…[4]. Most of the clinically utilized sensitizers are administered systemically, and so generalized adverse effects remain of great concern in daily clinical practice [5,6]. Radiosensitization that could work synergistically with local irradiation both spatially and temporally therefore warrants further exploration.…”

Ultrasound‐Triggered Enzymatic Gelation

“…We thus anticipate that the greatest benefit of this method will be in the ability to trigger catalysis or gelation in conventionally inaccessible scenarios found in industry (e.g., opaque containers/pipes), academia (e.g., closed microfluidic systems), and medicine (e.g., in vivo gelation). Many of these applications would require further optimization, e.g., an enzyme system with higher ion threshold would be required for in vivo applications, while the use of higher frequency focused ultrasound would enable more biocompatible and remote triggering . It should be noted that while transglutaminase was used as an exemplar in this work, this method is modular, with the cofactor loaded in the liposomes and the enzyme present in the surrounding solution.…”

“…Many of these applications would require further optimization, e.g., an enzyme system with higher ion threshold would be required for in vivo applications, while the use of higher frequency focused ultrasound would enable more biocompatible and remote triggering. [52] It should be noted that while transglutaminase was used as an exemplar in this work, this method is modular, with the cofactor loaded in the liposomes and the enzyme present in the surrounding solution. Thus, the exact same principles could be applied to other enzymes with ionic cofactors, which include many oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases.…”