A Glucose Biosensor Based on Phosphorescence Lifetime Sensing and a Thermoresponsive Membrane

Abstract

The adoption of existing continuous glucose monitors (CGMs) is limited by user burden. Herein, a design for a glucose biosensor with the potential for subcutaneous implantation, without the need for a transcutaneous probe or affixed transmitter, is presented. The design is based on the combination of an enzyme‐driven phosphorescence lifetime‐based glucose‐sensing assay and a thermoresponsive membrane anticipated to reduce biofouling. The metalloporphyrin, Pd meso‐tetra(sulfophenyl)‐tetrabenzoporphyrin ([PdPh4(SO3Na)4TBP]3, HULK) as well as glucose oxidase (GOx) are successfully incorporated into the UV‐cured double network (DN) membranes by leveraging electrostatic interactions and covalent conjugation, respectively. The oxygen‐sensitive metalloporphyrin is incorporated at different levels within the DN membranes. These HULK‐containing membranes retain the desired thermosensitivity, as well as glucose diffusivity and primary optical properties of the metalloporphyrin. After subsequently modifying the membranes with GOx, glucose‐sensing experiments reveal that membranes prepared with the lowest GOx level exhibit the expected increase in phosphorescent lifetime for glucose concentrations up to 200 mg dL−1. For membranes prepared with relatively higher GOx, oxygen‐limited behavior is considered the source of diminished sensitivity at higher glucose levels. This proof‐of‐concept study demonstrates the promising potential of a biosensor design integrating a specific optical biosensing chemistry into a thermoresponsive hydrogel membrane.

Silicone-containing thermoresponsive membranes to form an optical glucose biosensor

“…7d). In our prior work, 62 the SiHy -0 biosensor ( t ∼ 1.2 mm) exhibited glucose sensitivity limited to concentrations of 50 to 100 mg dL −1 . Herein, by reducing SiHy -0 biosensor thickness ( t ∼ 0.5 mm), glucose sensitivity was achieved from 100 to 150 mg dL −1 .…”

“…In our recent report, a distinct DN hydrogel membrane was prepared to leverage electrostatic interactions and covalent bonding with the assay components. 62 This membrane was based on a NIPAAm and cationic (3-acrylamidopropyl)trimethylammonium chloride at 75 : 25 mol% 1 st network [P(NIPAAm- co -APTAC)] and loosely crosslinked NIPAAm and acrylamide 2 nd network [P(NIPAAm- co -AAm)]. The VPTT was precisely tuned with AAm to afford the aforementioned targeted VPTT profile.…”

Enhancement of Sensitivity for Retroreflection‐Based Biosensor by Controlling Polymer Brush on Janus Particles

“…Biomolecular assays for proteins, peptides, and nucleic acids have played a key role in diagnosis and early detection. A broad range of methods have been reported, including strip-type (pregnancy test, [1][2][3][4][5][6] COVID-19 test [7][8][9] ), electrochemical sensing (field effect transistor type, [10][11][12][13] blood glucose sensor-type [14][15][16][17] ), and fluorescence type, [18][19][20][21][22] among others. Researchers have focused on increasing the sensitivity of these technologies for the early DOI: 10.1002/macp.202300382 detection of possible harmful substances, such as viruses and biological warfare agents.…”

Glucose biosensors based on Michael addition crosslinked poly(ethylene glycol) hydrogels with chemo-optical sensing microdomains

“…These sensors rely on materials that are engineered to transduce glucose concentration into an optical signal by combining an oxygen-sensitive phosphorescent metalloporphyrin dye with glucose oxidase (GOX). 10 GOX simultaneously consumes β- d -glucose and oxygen, resulting in a change in the phosphorescence emission lifetime of the porphyrin; if mass transfer is properly controlled to make the reaction glucose diffusion-limited, oxygen will be consumed in proportion to glucose concentration. 11 Phosphorescence lifetime is not dependent on implant depth or phosphor concentration, which eliminates the large variation that leads to inaccurate readings and the need for calibration.…”