Oxygen-Loaded Microbubbles for Sonodynamic Therapy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current treatments for deep-seated tumors, such as pancreatic cancer, are invasive and associated with significant side effects, limiting their efficacy and accessibility, especially for tumors that are difficult to reach with conventional photodynamic therapy (PDT) due to the limited penetration of visible light and the complexity of catheter-directed procedures.
Innovation Solution
The use of oxygen-loaded microbubbles conjugated with sonosensitisers and anti-metabolites, which are selectively targeted and activated by ultrasound, generating reactive oxygen species to destroy tumor cells while minimizing side effects through controlled delivery and release of both agents at the tumor site.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional chemotherapy and surgery are used to treat deep-seated tumors, then tumor treatment efficacy is improved, but patient side effects and surgical complexity increase significantly
Solution Approach 1:
The treatment approach segments the therapy into targeted components: microbubbles deliver sonosensitisers specifically to tumor sites, allowing localized activation by ultrasound. This segmentation enables effective tumor treatment while isolating the therapeutic action to the target site, thereby reducing systemic side effects compared to conventional chemotherapy.
Solution Approach 2:
Microbubbles serve as intermediaries that carry sonosensitisers to the tumor site and facilitate controlled release upon ultrasound exposure. This intermediary mechanism enables precise spatial and temporal control of drug delivery, improving treatment efficacy at the target while minimizing exposure and side effects in healthy tissues.
2Reliability
If photodynamic therapy is used to treat deep-seated tumors, then tumor cell destruction is achieved, but light penetration depth is insufficient and catheter procedures become complex
Solution Approach 1:
The patent replaces the optical activation mechanism of PDT with acoustic activation using ultrasound. Ultrasound waves can penetrate deep into tissues without requiring catheter insertion, substituting the complex mechanical catheter-delivery system with a non-invasive acoustic field that achieves the same therapeutic goal of activating sensitisers at the tumor site.
Solution Approach 2:
Ultrasound serves multiple functions in this approach: it activates the sonosensitisers bound to microbubbles, enables deep tissue penetration without catheters, and can be applied externally to reach tumors at various depths. This multi-functionality simplifies the overall procedure compared to catheter-directed PDT while maintaining effective tumor cell destruction.
3Length of stationary object
If microbubble-sonosensitiser complexes are used for SDT, then treatment penetration depth is improved, but oxygen availability in hypoxic tumors limits ROS generation
Solution Approach 1:
Oxygen-loaded microbubbles are administered beforehand to accumulate at the tumor site before ultrasound activation. This preliminary action ensures that oxygen is pre-positioned at the target location, so when the microbubbles are activated by ultrasound, immediate ROS generation can occur despite the hypoxic tumor environment, overcoming the limitation of insufficient oxygen availability.
Solution Approach 2:
The patent changes the oxygen parameter by loading microbubbles with oxygen gas, transforming them from oxygen-depleted to oxygen-rich carriers. This parameter change enables the microbubbles to serve as oxygen reservoirs that can locally supply oxygen for ROS generation upon activation, directly addressing the hypoxia limitation in deep-seated tumors.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the therapeutic index of sonodynamic therapy by increasing oxygen delivery and cytotoxic effects at the tumor site, reducing side effects and improving treatment outcomes for deep-seated tumors compared to conventional chemotherapy and PDT methods.
Implementation Method 1
activation of the sonosensitiser by acoustic energy results in the generation of reactive oxygen species
Implementation Method 2
Sonodynamic therapy (SDT) is a more recent concept and involves the combination of ultrasound and a sonosensitising drug
Implementation Method 3
The use of a microbubble also leads to a reduction in toxic side-effects due to the shielding of the sonosensitiser from potential light activation prior to reaching the desired target site
Data Source
AI summary
The invention relates to methods of sonodynamic therapy comprising the co-administration of a microbubble-chemotherapeutic agent complex together with a microbubble-sonosensitiser complex. It further relates to pharmaceutical compositions comprising these complexes and their use in methods of sonodynamic therapy and/or sonodynamic diagnosis. Such methods find particular use in the treatment of cancer, e.g. pancreatic cancer.