Molecular dosimeter for biological radiation dose

Abstract

A biological molecular dosimeter includes a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100); a radiation-sensitive molecule or nanoparticle (103) within the central cavity (106); and a fluid (104) within the central cavity (106) in which the radiation-sensitive molecule or nanoparticle (103) is suspended. The rsLNP has a central cavity (106), and a radiation-stable membrane (107) configured to protect the central cavity (106) and its contents from enzymatic and biological processes.

Description

MOLECULAR DOSIMETER FOR BIOLOGICAL RADIATION DOSESTATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0001] This invention was made with United States Government support from the National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce. The Government has certain rights in this invention.CROSS-REFERENCE TO RELATED APPLICATIONThis application claims the benefit of U.S. Provisional Patent Application No. 63 / 621 ,892, filed January 17, 2024, which is incorporated by reference herein in its entirety.COPYRIGHT NOTICE

[0002] This patent disclosure may contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the U.S. Patent and Trademark Office patent file or records, but otherwise reserves any and all copyright rights.BACKGROUND

[0003] The present invention generally relates to the fields of radiation and radiotherapy and more particularly to techniques and materials for measuring the effect of different ionizing radiation on different material.

[0004] Radiation is employed across many modern industries and for an enormous variety of purposes, ranging from the processing of materials to the sterilization of food to medical radiotherapy. Nonetheless, the effects of radiation remain difficult to predict, calculate, measure, or quantify.BRIEF DESCRIPTION

[0005] Disclosed is a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100).

[0006] Also disclosed is a method for using a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) as a biological molecular dosimeter to measure the effect of ionizing radiation on a radiation-sensitive molecule or nanoparticle (103), further utilizing such a measurement to retrospectively calculate absorbed dose on a material.

[0007] The current standard for quantifying radiation delivery in any prescribed scenario is the absorbed dose - the energy per unit mass - and neither the type of radiation nor its target is taken into account.

[0008] Ionizing radiation may be of different types with varying energy and interaction characteristics, leading to different effects on the material absorbing the radiation, even if the absorbed dose of radiation is the same.

[0009] Likewise, different materials may be more or less susceptible to the effects of ionizing radiation, such as crosslinking, fragmentation, and free radical formation, even if the absorbed dose is constant.

[0010] The current state of radiotherapy requires clinicians to estimate the necessary dose of ionizing radiation using methods that can result in large uncertainties.

[0011] Further, biological dosimetry measurements are often confounded by enzymatic processes taking place within an organism, such as enzymatic digestion or DNA repair.

[0012] Greater reliability in assessing the effects of ionizing radiation and calculating dosages might be achieved through materials and methods that are resistant to the inner enzymatic processes of living organisms, allowing for a clearer measure of the true absorbed dose regardless of biological repair mechanisms.

[0013] Greater reliability in assessing the effects of ionizing radiation and calculating dosages would enhance the precision of radiotherapies, potentially leading to improved patient outcomes.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The following descriptions cannot be considered limiting in any way. Various objectives, features, and advantages of the disclosed subject matter can be more fully appreciated with reference to the following detailed description of the disclosed subject matter when considered in connection with the following drawings, in which like reference numerals identify like elements.

[0015] FIG. 1 shows a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) in cross-section, according to some embodiments.

[0016] FIG. 2 shows a method for using a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) to measure the effect of ionizing radiation on a radiation-sensitive molecule or nanoparticle (103), further utilizing such a measurement to retrospectively calculate absorbed dose on a material, according to some embodiments.

[0017] FIG. 3 shows a method for using a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) to measure the effect of ionizing radiation on a radiation-sensitive molecule or nanoparticle (103), further utilizing such a measurement to retrospectively calculate absorbed dose on a tissue, according to some embodiments.DETAILED DESCRIPTION

[0018] A detailed description of one or more embodiments is presented herein by way of exemplification and not limitation.

[0019] A biological molecular dosimeter measures ionizing radiation. In an embodiment, with reference to FIG. 1 , a biological molecular dosimeter includes: a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100), which itselfhas a central cavity (106) and a radiation-stable membrane (107) configured to protect the central cavity (106) and its contents from enzymatic and biological processes; a radiation-sensitive molecule or nanoparticle (103) within the central cavity (106); and a fluid (104) within the central cavity (106) in which the radiation-sensitive molecule or nanoparticle (103) is suspended.

[0020] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-stable membrane (107) comprising a plurality of amphiphilic molecules (105), and wherein each amphiphilic molecule comprises a polar hydrophilic head group (101 ) and a non-polar hydrophobic tail (102).

[0021] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-stable membrane (107) comprising a plurality of amphiphilic molecules (105) having a concentration of carbon-to-carbon double bonds sufficient to impart radiation stability.

[0022] Although depicted for clarity as having a bilayer membrane comprising a plurality of lipid-like molecules, optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-stable membrane (107) comprising: a plurality of diblock-copolymers (forming a bilayer membrane); a plurality of triblock-copolymers (in which hydrophilic head groups 101 bind on both sides of a hydrophobic tail 102 forming a monolayer membrane); or a plurality of sequence-defined polymers based on artificial lipids or poly-peptoids.

[0023] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-stable membrane (107) from two to ten nanometers in length.

[0024] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-stable membrane (107) configured to protect the central cavity (106) and its contents from enzymatic and biological processes.

[0025] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-sensitive molecule or nanoparticle(103) within the central cavity (106) and wherein the radiation-sensitive molecule or nanoparticle (103) is a known size, sequence, or structure.

[0026] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a radiation-sensitive molecule or nanoparticle (103) within the central cavity (106), and wherein the radiation-sensitive molecule or nanoparticle (103) comprises one of a DNA segment; a protein; a peptide; or a known physical standard.

[0027] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a fluid (104) within the central cavity (106), and wherein the fluid (104) is configured to mimic the composition of the medium under investigation.

[0028] Optionally, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) includes a fluorescent dye.

[0029] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be used to measure the effect of the absorbed dose on a targeted material. In an embodiment, with reference to FIG. 2, a method for using a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is shown at 200. At block 210, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is introduced into a material. At block 220, ionizing radiation is applied to the material. At block 230, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is retrieved from the irradiated material. At block 240, the radiation-sensitive molecule or nanoparticle (103) is extracted from the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100). At block 250, the effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103) is measured. At block 260, the measurement is used to retrospectively calculate absorbed dose on a material.

[0030] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be used to measure the effect of the absorbed dose on a tissue. In an embodiment, with reference to FIG. 3, a method for using a radiation-stabilized synthetic liposomal like nanoparticle (rsLNP) (100) is shown at 300. At block 310, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is introduced into a tissue. At block 320, ionizing radiation is applied to the tissue. At block 330,the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is retrieved from the irradiated material. At block 350, the radiation-sensitive molecule or nanoparticle (103) is extracted from the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100). At block 360, the effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103) is measured. At block 360, the measurement is used to retrospectively calculate absorbed dose on a material.

[0031] Optionally, at block 301 , he process may begin with the generation of artificial tissue configured to mimic the structure and composition of a target tissue.

[0032] Optionally, at block 302, the central cavity (106) of the radiation- stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may contain a fluid (104) configured to mimic the conditions present in a target tissue. In such an embodiment, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be introduced into an artificial tissue.

[0033] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be prepared using any of a number of conventional methods for the preparation of a liposome that are known in the art, many of which are driven by the self-assembling nature of liposomes.

[0034] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be prepared by methods including: mechanical extrusion through a porous membrane; electroformation; or with a continuous-flow microfluidic device, for example.

[0035] One exemplary method for the preparation of a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may include: dissolving an amphiphilic molecule (105) and a radiation-sensitive molecule or nanoparticle (103) in an organic solvent; spreading the solution across a clean glass surface; evaporating the solvent to leave a thin film; resuspending the material remaining on the glass surface in a fluid (104); and reducing the size of the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) by extrusion through a membrane or sonicating in a bath.

[0036] Another exemplary method for the preparation of a radiation- stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may include: dissolving an amphiphilic molecule (105) in an organic solvent; dissolving a radiation-sensitive molecule or nanoparticle (103) in a fluid (104); and utilizing microfluidic hydrodynamic focusing on the materials.

[0037] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be introduced into a material or tissue using any of a number of conventional methods that are known in the art, including through electroporation or a similar loading process, for example.

[0038] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be identified within a material or tissue using any of a number of conventional methods that are known in the art, including by introducing a fluorescent dye into the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP), for example.

[0039] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be retrieved from a material or tissue using any of a number of conventional methods that are known in the art, including through chromatography or electrophoresis, for example.

[0040] Measuring the effect of ionizing radiation on a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) may be performed using any of a number of conventional methods that are known in the art, including through gel electrophoresis, mass spectrometry, or nanopore spectroscopy, for example.

[0041] One exemplary method for measuring the effect of ionizing radiation on a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) comprising a radiation-sensitive molecule or nanoparticle (103) that is DNA may include: extracting the irradiated DNA from the central cavity (106) of the radiation- stabilized synthetic liposomal-like nanoparticle (rsLNP) (100); detecting radiation- induced DNA lesions by attaching neutral water soluble polymers to the DNA through site-directed enzymatic processes; and quantitating the DNA-lesions using molecular counting tools, such as a resistive pulse nanopore detector.

[0042] A radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) has numerous advantages as a biological molecular dosimeter. First, a radiation- stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) has a radiation-stable membrane (107) configured to protect the central cavity (106) and its contents from enzymatic and biological processes. This protection may include protecting the central cavity (106) from outside enzymatic and / or chemical / biological processes, such as those that occur naturally within living organisms and humans specifically. These processes, including enzymatic digestion and DNA repair, often render biological dosimetry measurements unreliable, as they may cloak the effects of ionizing radiation on a human tissue. Employing a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) with a radiation-stable membrane (107) prevents those naturally occurring processes from altering a radiation-sensitive molecule or nanoparticle (103) within the central cavity (106) of the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) after irradiation. Such a radiation-stable membrane (107) provides such protection from the naturally occurring processes of the surrounding tissue without interfering with the effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103) contained within the central cavity (106). I.e., the radiation-stable membrane (107) neither diminishes nor enhances the ionizing radiation and its effects on the radiation-sensitive molecule or nanoparticle (103). Further, the radiation-stable membrane (107) allows the radiation-sensitive molecule or nanoparticle (103) to be suspended in a fluid (104) configured to mimic the surrounding environment without making the radiation-sensitive molecule or nanoparticle (103) vulnerable to such environment.

[0043] After the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is retrieved from an irradiated tissue, the effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103) contained within the central cavity (106) and protected by the radiation-stable membrane (107) may be measured, and such a measurement of the effect of ionizing radiation will offer a high degree of confidence, particularly as compared with a biological dosimeter that has been vulnerable to the naturally occurring processes in the surrounding tissue.

[0044] In a biological dosimeter utilizing DNA as a radiation-sensitive molecule or nanoparticle (103) where the effect of ionizing radiation is calculated bymeasuring the number of chemical bonds broken within the DNA molecule after irradiation, the biological dosimeter and its contents may be vulnerable to naturally occurring processes within the surrounding tissue. These processes can alter the DNA after irradiation, including the introduction of additional broken chemical bonds or the repair of already broken chemical bonds. As a result, the measurement of chemical bond breaks attributable to the ionizing radiation may become confounded by these biological processes, leading to uncertainty in the assessment of radiation-induced damage. Therefore, conventional biological dosimeters subject to repair mechanisms do not reflect the true extent of damage caused by the absorbed dose.

[0045] By comparison, a biological molecular dosimeter can utilize a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100). This nanoparticle features a radiation-stable membrane (107) configured to protect the central cavity (106) and a radiation-sensitive molecule or nanoparticle (103), such as, for example, DNA, from the effects of external enzymatic processes in the surrounding tissue. With this protection, the effect of ionizing radiation on the DNA - specifically, the number of the broken chemical bonds attributable to the quantity and type of absorded radiation- can be measured. In such an instance, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) can be introduced into either the target tissue of an organism or an artificial tissue configured to mimic the structure and composition of the target tissue. After irradiation, the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is retrieved, and the DNA extracted from it will exhibit only those chemical bond breaks that are attributable to the absorbed ionizing radiation.

[0046] In addition, where such a radiation-sensitive molecule or nanoparticle (103) is suspended in a fluid (104) configured to mimic the composition of a target tissue within the central cavity (106) of the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) with a radiation-stable membrane (107) that is configured to protect the central cavity (106) and its contents from the effects of natural processes occurring in the surrounding tissue, the effect of ionizing radiation on the radiationsensitive molecule or nanoparticle (103) will form a precise basis for calculating the effect of ionizing radiation on the target tissue.

[0047] Many other variations than those described herein will be apparent from this disclosure. For example, depending on the embodiment, certain acts, events, or functions described herein can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the invention). Moreover, in certain embodiments, acts or events can be performed concurrently, rather than sequentially. In addition, different tasks or processes may be performed independently.

[0048] While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. Embodiments herein can be used independently or can be combined.

[0049] All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The ranges are continuous and thus contain every value and subset thereof in the range. Unless otherwise stated or contextually inapplicable, all percentages, when expressing a quantity, are weight percentages. The suffix (s) as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including at least one of that term (e.g., the colorant(s) includes at least one colorants). Option, optional, or optionally means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event occurs and instances where it does not. As used herein, combination is inclusive of blends, mixtures, alloys, reaction products, collection of elements, and the like.

[0050] As used herein, a combination thereof refers to a combination comprising at least one of the named constituents, components, compounds, or elements, optionally together with one or more of the same class of constituents, components, compounds, or elements.

[0051] All references are incorporated herein by reference.

[0052] The use of the terms “a,” “an,” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwiseindicated herein or clearly contradicted by context. It can further be noted that the terms first, second, primary, secondary, and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. For example, a first current could be termed a second current, and, similarly, a second current could be termed a first current, without departing from the scope of the various described embodiments. The first current and the second current are both currents, but they are not the same condition unless explicitly stated as such.

[0053] The modifier about used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity). The conjunction or is used to link objects of a list or alternatives and is not disjunctive; rather the elements can be used separately or can be combined together under appropriate circumstances.

Claims

CLAIMS1 . A biological molecular dosimeter comprising: a radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) including: a central cavity (106); and a radiation-stable membrane (107) configured to protect the central cavity (106) and contents of the central cavity from enymatic and biological processes; a radiation-sensitive molecule or nanoparticle (103) within the central cavity (106); and a fluid (104) within the central cavity (106) in which the radiation-sensitive molecule or nanoparticle (103) is suspended.

2. The biological molecular dosimeter of claim 1 , wherein a diameter of the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) is 100-1000 nanometers.

3. The biological molecular dosimeter of any preceding claim, wherein the radiation-stable membrane (107) includes a plurality of amphiphilic molecules (105), wherein each of the amphiphilic molecules includes a polar hydrophilic head group (101 ) and a non-polar hydrophobic tail (102).

4. The biological molecular dosimeter of any preceding claim, wherein the radiation-stable membrane (107) includes one of a a diblock-copolymer, a triblockcopolymer, or a sequence-defined polymer.

5. The biological molecular dosimeter of any preceding claim, wherein the radiation-stable membrane (107) has a length of 2-10 nanometers.

6. The biological molecular dosimeter of any preceding claim, wherein the radiation-stable membrane (107) is configured to protect the central cavity (106) and its contents from enzymatic and biological processes.

7. The biological molecular dosimeter of any preceding claim, wherein the radiation-sensitive molecule or nanoparticle (103) is a known size, sequence, or structure.

8. The biological molecular dosimeter of any preceding claim, wherein the radiation-sensitive molecule or nanoparticle (103) includes one of DNA, a protein, a peptide, a carbohydrate, or a known physical standard.

9. The biological molecular dosimeter of any preceding claim, wherein the fluid (104) is configured to mimic a composition of a medium under investigation.

10. The biological molecular dosimeter of any preceding claim, further comprising a fluorescent dye.11 . A method for calculating an absorbed dose on a target material, the method comprising the steps of: introducing the radiation-stabilized synthetic lipsomal-like nanoparticle (rsLNP) (100) of any preceding claim into a material; applying ionizing radiation to the material; retrieving the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100) from the irradiated material; extracting the radiation-sensitive molecule or nanoparticle (103) from the radiation-stabilized synthetic liposomal-like nanoparticle (rsLNP) (100); measuring an effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103); and using the measured effect of the ionizing radiation on the radiation-sensitive molecule or nanoparticle (103) to calculate the absorbed dose on the target material.

12. The method for calculating an absorbed dose on a target material of claim 11 , wherein the material includes a biological tissue or an artificial tissue configured to mimic a target biological tissue.

13. The method for calculating an absorbed dose on a target material of either one of claims 11 or 12, wherein the step of measuring includes using a resistive pulse nanopore detector.

14. The method for calculating an absorbed dose on a target material of any one of claims 11 -13, wherein the target material is a biological or artificial tissue and the radiation-sensitive molecule or nanoparticle (103) is DNA, and wherein the method further comprises the steps of: extracting the irradiated DNA from the central cavity (106) of the radiation- stabilized synthetic liposomal-like nanoparticle (100); and quantitating DNA lesions.

15. The method for calculating an absorbed dose on a target material of claim 14, wherein the step of quantitating includes using a resistive pulse nanopore detector.

16. The method for caclulating an absorbed dose on a target material of any one of claims 11-15, further comprising the steps of: comparing properties of the extracted radiation-sensitive molecule or nanoparticle (103) to a comprehensive reference dataset of effects of known types and quantities of absorbed dose on like radiation-sensitive molecule or nanoparticles (103); identifying a type and quantity of absorbed dose on the extracted radiationsensitive molecule or nanoparticle (103) based on the comparison.

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