Sugar-Breathing Glycopolymersomes for Regulating Glucose Level

Abstract

Diabetes mellitus is a chronic, life-threatening illness that affects people of every age and ethnicity. It is a long-term pain for those who are affected and must regulate their blood glucose level by frequent subcutaneous injection of insulin every day. Herein, we propose a noninsulin and antidiabetic drug-free strategy for regulating blood glucose level by a nanosized "sugar sponge" which is a lectin-bound glycopolymersome capable of regulating glucose due to the dynamic recognition between the lectin and different carbohydrates. The glycopolymersome is self-assembled from poly(ethylene oxide)-block-poly[(7-(2-methacryloyloxyethoxy)-4-methylcoumarin)-stat-2-(diethylamino)ethyl methacrylate-stat-(α-d-glucopyranosyl)ethyl methacrylate] [PEO-b-P(CMA-stat-DEA-stat-GEMA)]. The lectin bound in the glycopolymersome has different affinity for the glucose in the blood and the glucosyl group in the glycopolymersome. Therefore, this sugar sponge functions as a glucose storage unit by dynamic sugar replacement: The lectin in the sugar sponge will bind and store the glucose from its surrounding solution when the glucose concentration is too high and will release the glucose when the glucose concentration is too low. In vitro, this sugar-breathing behavior is characterized by a remarkable size change of the sugar sponge due to the swelling/shrinkage at high/low glucose levels, which can be used for blood sugar monitoring. In vivo, this sugar sponge showed an excellent antidiabetic effect for type I diabetic mice within 2 days upon one dose, which is much longer than traditional long-acting insulin. Overall, this concept of "controlling sugar levels with sugar" opens new avenues for regulating the blood glucose level without the involvement of insulin or other antidiabetic drugs.

Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry

“…Therefore chlorine desorption and full-copper-monolayer formation are plausible explanations 50,52,53 of the two peaks, with our first-principles predictions reproducing well the peak spacing (0.09 eV versus 0.12 eV in experiment), and placing the absolute locations of the peaks to within 0.07 eV. Similar accuracy has been achieved in comparison to experiment for onset potentials and product selectivity in CO reduction on Cu(111) 15,56 and the oxygen evolution reaction on IrO2(110) 57 in concurrent work using exactly the same calculation protocol as here: fixed-potential DFT in JDFTx using the PBE exchangecorrelation functional and the CANDLE solvation model. The partial 2x2 monolayer of copper (Figure 12(d)) proposed by others 51 as the reason for the second peak is not the most stable configuration in our calculations at any potential, lying a significant 0.3 eV above the other phases at relevant potentials.…”

Electrochemical CO Reduction Builds Solvent Water into Oxygenate Products

“…[11][12][13][14] It is generally accepted that on various Cu surfaces, CO 2 reduces first to CO. 15,16 At low pH, CO can further reduce to *HCO or *OCH and then to *CH 2 OH, leading to methane or methanol formation. 14,17 At pH> 7, CO can undergo C-C coupling to generate a *CO-CO dimer, 14,[17][18][19][20][21] which then forms *OC-COH. 22 Subsequent steps leading to ethylene and ethanol have been further studied in quantum mechanics (QM) based theory papers.…”

“…22 Subsequent steps leading to ethylene and ethanol have been further studied in quantum mechanics (QM) based theory papers. [17][18][19][23][24][25] Recently, we published the first complete determination of the atomistic reaction mechanism for reduction of CO on Cu (100) using QM based metadynamics in full solvent to determine the free-energy barriers and kinetics at 298 K. 18 We showed that sol-vent water on the Cu surface plays an essential role in the mechanisms by providing hydrogen to the intermediates and products. This role of surface water, which involves transferring hydrogen to these intermediates, often through a Grotthuss mechanism involving other solvent waters, was a new result.…”

Glucose‐Responsive Insulin and Delivery Systems: Innovation and Translation

“…Mater. 2020, 32,1902004 www.advmat.de www.advancedsciencenews.com polymer grafted with glucose for glucose breathing, [71] and coassembly from Con A and amylopectin [72] have also been studied.…”