Contact lens containing a photonic crystal

Patent metadata

Field	Value
Publication number	US-2018267331-A1
Application number	US-201715789440-A
Country	US
Kind code	A1
Filing date	Oct 20, 2017
Priority date	Mar 17, 2017
Publication date	Sep 20, 2018
Grant date	—

Abstract

A contact lens containing a photonic crystal which is configured to change color depending on a concentration of an analyte in the tears of a subject. The change in color is reversible. The contact lens may be useful for monitoring the concentration of glucose in tears of a diabetic subject or a prediabetic subject.

First claim

1 . A contact lens, comprising:
a photonic crystal comprising:
a plurality of metal nanoparticle stacks comprising metal nanoparticles, wherein the plurality of metal nanoparticle stacks are spaced such that each metal nanoparticle stack is substantially parallel to one another; and
a hydrogel matrix comprising polyhydroxyethylmethacrylate;
wherein the plurality of metal nanoparticle stacks is arranged within the hydrogel matrix.

2 . The contact lens of claim 1 , wherein the metal nanoparticles comprise at least one metal selected from the group consisting of silver, gold, titanium, platinum, iron, cobalt, chromium, molybdenum, vanadium, tin, nickel, and niobium.

3 . The contact lens of claim 1 , wherein each metal nanoparticle stack comprises 20-200 metal nanoparticles.

4 . The contact lens of claim 1 , wherein the photonic crystal comprises up to 100 metal nanoparticle stacks.

5 . The contact lens of claim 4 , wherein the photonic crystal comprises 3-6 metal nanoparticle stacks.

6 . The contact lens of claim 1 , wherein a distance between adjacent metal nanoparticle stacks is in a range of 140-250 nm.

7 . The contact lens of claim 1 , wherein the plurality of metal nanoparticle stacks has a tilt angle in a range of 1-30° measured from a plane of a metal nanoparticle stack to a surface plane of the photonic crystal.

8 . The contact lens of claim 1 , wherein the metal nanoparticles are substantially spherical.

9 . The contact lens of claim 1 , wherein the metal nanoparticles have an average diameter in a range of 2-20 nm.

10 . The contact lens of claim 9 , wherein the average diameter of the metal nanoparticles varies between each metal nanoparticle stack.

11 . The contact lens of claim 1 , wherein the metal nanoparticles are randomly dispersed within each metal nanoparticle stack.

12 . The contact lens of claim 1 , wherein each metal nanoparticle stack comprises metal nanoparticles of substantially uniform diameter.

13 . The contact lens of claim 1 , wherein a distance between adjacent metal nanoparticle stacks increases or decreases in response to a concentration of an analyte thereby producing a shift in a photonic band gap and a color change in the photonic crystal.

14 . The contact lens of claim 13 , wherein the shift in the photonic band gap is reversible.

15 . The contact lens of claim 13 , wherein the color change is reversible.

16 . The contact lens of claim 13 , wherein the analyte is glucose.

17 . The contact lens of claim 16 , further comprising a sensor for measuring the shift in photonic band gap.

18 . A method for detecting a glucose concentration of a subject, the method comprising:
wearing the contact lens of claim 17 , thereby contacting the contact lens to tears produced by the subject; and detecting the shift in the photonic band gap.

19 . The method of claim 18 , wherein the photonic crystal changes color in response to the glucose concentration in the tears.

20 . The method of claim 18 , wherein the subject has diabetes.

Assignees

• Univ Imam Abdulrahman Bin Faisal

Inventors

• Abbasi Badaruddin
• Almasoud Naif Nasser

Classifications

• A61B5/14532

  for measuring glucose, e.g. by tissue impedance measurement · CPC title

• G02C7/049 Primary

  Contact lenses having special fitting or structural features achieved by special materials or material structures · CPC title

• A61B5/6821

  Eye · CPC title

• A61B5/14546

  for measuring analytes not otherwise provided for, e.g. ions, cytochromes · CPC title

• A61B5/14551

  for measuring blood gases · CPC title