Protease-Activated Melanin Precursors for Naked-Eye Tumor Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical surgical navigation using fluorescent contrast agents is hindered by the need for instrumentation, darkened operating conditions, and regulatory challenges, and there is a desire for naturally-occurring, biocompatible contrast agents that provide optical contrast visible to the naked eye without additional instrumentation.
Innovation Solution
A composition comprising a melanin precursor that spontaneously synthesizes melanin in vivo, covalently bonded or indirectly linked to a peptide, which blocks melanin synthesis in healthy tissue but activates in tumors with protease activity, allowing for optical surgical navigation using melanin contrast.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If fluorescent contrast agents are used for optical surgical navigation, then tumor detection capability is improved, but device complexity and regulatory burden increase
Solution Approach 1:
The patent employs melanin, a naturally-occurring pigment that serves as its own contrast agent. Tumor cells naturally produce melanin or can be engineered to do so, eliminating the need for external fluorescent agents and complex imaging instrumentation. The melanin itself provides the optical contrast needed for tumor visualization during surgery.
Solution Approach 2:
The invention extracts and utilizes the naturally-occurring melanin pigment from biological systems, removing the need for synthetic fluorescent contrast agents. By leveraging endogenous melanin production or simple melanin administration, the complex regulatory and instrumentation requirements of fluorescent agents are eliminated.
2Measurement precision
If fluorescent contrast agents are used, then tumor highlighting is improved, but operating conditions become more restrictive
Solution Approach 1:
Melanin provides intrinsic optical absorption properties that create contrast without requiring external fluorescence excitation sources or specialized imaging systems. This allows surgeons to operate under normal lighting conditions while still achieving effective tumor visualization through the natural optical properties of melanin.
3Measurement precision
If fluorescent contrast agents are used, then tumor visibility is improved, but compliance and regulatory burden increase
Solution Approach 1:
The invention replaces synthetic fluorescent contrast agents with naturally-occurring melanin, a substance that is already present in biological systems and has established safety profiles. This extraction of the contrast function from synthetic agents to natural pigments significantly reduces regulatory hurdles and compliance requirements.
Solution Approach 2:
By using melanin, a substance that is chemically and biologically similar to endogenous pigments already present in the body, the invention achieves better compatibility and reduces regulatory concerns associated with introducing foreign synthetic molecules into the human body.
4Measurement precision
If melanin precursor is linked to peptide, then spontaneous melanin synthesis is blocked in healthy tissue, but tumor detection is enabled through protease activity
Solution Approach 1:
The melanin precursor is pre-linked to a peptide sequence that acts as a protective block, preventing spontaneous melanin synthesis in healthy tissue. This preliminary blocking action ensures that melanin production only occurs when and where the specific protease is active, namely in tumor cells, thereby achieving selective activation without complex delivery systems.
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
Enables efficient tumor detection and resection guided by melanin contrast visible to the naked eye, reducing the need for fluorescence-based instrumentation and improving surgical precision.
Implementation Method 1
a melanin precursor that spontaneously synthesizes a melanin when in free form in vivo
Implementation Method 2
a peptide directly covalently bonded to or indirectly linked to the melanin precursor, wherein the direct covalent bond or indirect link of the peptide to the melanin precursor blocks spontaneous synthesis of the melanin
Implementation Method 3
the direct covalent bond or indirect link of the peptide to the melanin precursor blocks spontaneous synthesis of the melanin in vivo in the absence of protease activity
Implementation Method 4
surgically resecting the tumor, wherein the surgical resection is guided at least in part by contrast imparted by the melanin
Data Source
AI summary
We disclose a composition, comprising a compound, comprising a melanin precursor that spontaneously synthesizes a melanin when in free form in vivo, and a peptide directly covalently bonded to or indirectly linked to the melanin precursor, wherein the direct covalent bond or indirect link of the peptide to the melanin precursor blocks spontaneous synthesis of the melanin in vivo in the absence of protease activity. We also disclose methods of tumor imaging, tumor detection, diagnosis, and treatment, including methods comprising administering, to a patient suffering from a tumor, the composition; and either surgically resecting the tumor or thermally ablating the tumor, wherein the surgical resection is guided at least in part by contrast imparted by, or the thermally ablating targets cells containing, the melanin, wherein the melanin is spontaneously synthesized in the tumor after administering the composition.