# US 8,999,720 B2 · Aqueous radiation protecting formulations and methods for making and using them

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,999,720 B2
- Document ID: US8999720B2
- Status: Granted
- Kind: B2
- Application number: 13/660,648
- Filed: 2012-10-25
- Published: 2013-05-23
- Granted: 2015-04-07
- Earliest claimed: 2011-11-17
- Assignees: Medtronic MiniMed, Inc.
- Applicants: Medtronic MiniMed, Inc.
- Inventors: Jesper Svenning Kristensen; Soren Aasmul
- Web page: https://patentgrep.com/patent/US8999720B2

## CPC

- A61L 2/087: Particle radiation, e.g. electron-beam, alpha or beta radiation
- A61B 5/14532: {for measuring glucose, e.g. by tissue impedance measurement}
- A61B 5/1455: using optical sensors, e.g. spectral photometrical oximeters
- A61B 5/14735: {comprising an immobilised reagent}
- A61B 5/14865: {invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors}
- A61L 2/081: Gamma radiation
- G01N 33/5308: {for analytes not provided for elsewhere, e.g. nucleic acids, uric acid, worms, mites}
- A61B 2562/12: Manufacturing methods specially adapted for producing sensors for in-vivo measurements
- A61B 2562/18: Shielding or protection of sensors from environmental influences, e.g. protection from mechanical damage
- A61L 2/02: using physical processes
- A61L 2103/15: Laboratory, medical or dentistry appliances, e.g. catheters or sharps
- A61L 2202/14: Means for controlling sterilisation processes, data processing, presentation and storage means, e.g. sensors, controllers, programs
- G01N 2400/00: Assays, e.g. immunoassays or enzyme assays, involving carbohydrates
- G01N 2458/00: Labels used in chemical analysis of biological material
- Y10T 436/14: Heterocyclic carbon compound [i.e. , O, S, N, Se, Te, as only ring hetero atom]
- Y10T 436/142222: Hetero-O [e.g., ascorbic acid, etc.]
- Y10T 436/143333: Saccharide [e.g., DNA, etc.]
- Y10T 436/144444: Glucose
- A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K)
- A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D)
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Medical devices are typically sterilized in processes used to manufacture such products and their sterilization by exposure to radiation is a common practice. Radiation has a number of advantages over other sterilization processes including a high penetrating ability, relatively low chemical reactivity, and instantaneous effects without the need to control temperature, pressure, vacuum, or humidity. Unfortunately, radiation sterilization can compromise the function of certain components of medical devices. For example, radiation sterilization can lead to loss of protein activity and/or lead to bleaching of various dye compounds. Embodiments of the invention provide methods and materials that can be used to protect medical devices from unwanted effects of radiation sterilization.

## Claims

### Claim 1

A method of inhibiting damage to a saccharide sensor that can result from a radiation sterilization process, the method comprising combining the saccharide sensor with an aqueous radioprotectant formulation during the sterilization process, wherein:
the saccharide sensor comprises a saccharide binding polypeptide having a carbohydrate recognition domain;
the aqueous radioprotectant formulation comprises a saccharide selected for its ability to bind the saccharide binding polypeptide; and
performing the sterilization process under conditions selected so that the saccharide binds the saccharide binding polypeptide, thereby inhibiting damage to the saccharide sensor that can result from the radiation sterilization process.

### Claim 2 (depends on 1)

The method of claim 1, wherein the saccharide binding polypeptide comprises mannan binding lectin, concanavalin A or glucose oxidase.

### Claim 3 (depends on 1)

The method of claim 1, wherein the saccharide comprises glucose, mannose, fructose, melizitose, N-acetyl-D-glucosamine, sucrose or trehalose.

### Claim 4 (depends on 1)

The method of claim 1, wherein the aqueous radioprotectant formulation comprises an antioxidant selected from the group consisting of ascorbate, urate, nitrite, vitamin E, α-tocopherol or nicotinate methylester.

### Claim 5 (depends on 1)

The method of claim 1, wherein:
the saccharide sensor comprises a fluorophore; and
the aqueous radioprotectant formulation comprises a fluorophore quenching composition selected for its ability to quench the fluorophore.

### Claim 6 (depends on 1)

The method of claim 1, wherein the aqueous radioprotectant formulation comprises a buffering agent.

### Claim 7 (depends on 6)

The method of claim 6, wherein the buffering agent is selected from the group consisting of citrate, tris(hydroxymethyl)aminomethane (TRIS) and tartrate.

### Claim 8 (depends on 1)

The method of claim 1, wherein the radiation sterilization process comprises a single dose of radiation.

### Claim 9 (depends on 1)

The method of claim 1, wherein the radiation sterilization process comprises electron beam irradiation.

### Claim 10

A composition of matter comprising:
a saccharide sensor comprising:
a saccharide binding polypeptide having a carbohydrate recognition domain; and
a fluorophore; and
an aqueous radioprotectant formulation comprising:
a saccharide, wherein the saccharide is bound to the carbohydrate recognition domain;
an antioxidant compound, wherein the antioxidant compound is selected from the group consisting of ascorbate, urate, nitrite, vitamin E, α-tocopherol or nicotinate methylester; and
a fluorophore quenching composition.

### Claim 11 (depends on 10)

The composition of claim 10, wherein the fluorophore quenching composition comprises acetaminophen.

### Claim 12 (depends on 11)

The composition of claim 11, wherein the aqueous radioprotectant formulation comprises acetaminophen in a concentration of at least 1 mM to 50 mM.

### Claim 13 (depends on 10)

The composition of claim 10, wherein the aqueous radioprotectant formulation comprises ascorbate in a concentration of at least 1 mM to 100 mM.

### Claim 14 (depends on 10)

The composition of claim 10, wherein the saccharide is selected from the group consisting of glucose, mannose, fructose, melizitose, N-acetyl-D-glucosamine, sucrose or trehalose.

### Claim 15 (depends on 14)

The composition of claim 14, wherein the aqueous radioprotectant formulation comprises mannose in a concentration of at least 1 mM to 100 mM.

### Claim 16 (depends on 14)

The composition of claim 14, wherein the aqueous radioprotectant formulation comprises sucrose in a concentration of at least 10 mM to 1000 mM.

### Claim 17 (depends on 10)

The composition of claim 10, wherein the aqueous radioprotectant formulation comprises a buffering agent; and has a pH of 6 or below.

### Claim 18 (depends on 17)

The composition of claim 17, wherein the buffering agent is selected from the group consisting of citrate, tris(hydroxymethyl)aminomethane (TRIS) and tartrate.

### Claim 19 (depends on 10)

The composition of claim 10, wherein the aqueous radioprotectant formulation comprises a surfactant.