Chemical and Biomolecular Engineering - Research Publications
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ItemAn Engineered Nanosugar Enables Rapid and Sustained Glucose-Responsive Insulin Delivery in Diabetic Mice(WILEY-V C H VERLAG GMBH, 2023-03-12)Glucose-responsive insulin-delivery platforms that are sensitive to dynamic glucose concentration fluctuations and provide both rapid and prolonged insulin release have great potential to control hyperglycemia and avoid hypoglycemia diabetes. Here, biodegradable and charge-switchable phytoglycogen nanoparticles capable of glucose-stimulated insulin release are engineered. The nanoparticles are "nanosugars" bearing glucose-sensitive phenylboronic acid groups and amine moieties that allow effective complexation with insulin (≈95% loading capacity) to form nanocomplexes. A single subcutaneous injection of nanocomplexes shows a rapid and efficient response to a glucose challenge in two distinct diabetic mouse models, resulting in optimal blood glucose levels (below 200 mg dL-1 ) for up to 13 h. The morphology of the nanocomplexes is found to be key to controlling rapid and extended glucose-regulated insulin delivery in vivo. These studies reveal that the injected nanocomplexes enabled efficient insulin release in the mouse, with optimal bioavailability, pharmacokinetics, and safety profiles. These results highlight a promising strategy for the development of a glucose-responsive insulin delivery system based on a natural and biodegradable nanosugar.
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ItemEngineering Flexible Metal-Phenolic Networks with Guest Responsiveness via Intermolecular Interactions(WILEY-V C H VERLAG GMBH, 2023-03-24)Flexible metal-organic materials are of growing interest owing to their ability to undergo reversible structural transformations under external stimuli. Here, we report flexible metal-phenolic networks (MPNs) featuring stimuli-responsive behavior to diverse solute guests. The competitive coordination of metal ions to phenolic ligands of multiple coordination sites and solute guests (e.g., glucose) primarily determines the responsive behavior of the MPNs, as revealed experimentally and computationally. Glucose molecules can be embedded into the dynamic MPNs upon mixing, leading to the reconfiguration of the metal-organic networks and thus changes in their physicochemical properties for targeting applications. This study expands the library of stimuli-responsive flexible metal-organic materials and the understanding of intermolecular interactions between metal-organic materials and solute guests, which is essential for the rational design of responsive materials for various applications.
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Item2-nm-Thick Indium Oxide Featuring High Mobility(WILEY, 2023-02-25)Thin film transistors (TFTs) are key components for the fabrication of electronic and optoelectronic devices, resulting in a push for the wider exploration of semiconducting materials and cost-effective synthesis processes. In this report, a simple approach is proposed to achieve 2-nm-thick indium oxide nanosheets from liquid metal surfaces by employing a squeeze printing technique and thermal annealing at 250 °C in air. The resulting materials exhibit a high degree of transparency (>99 %) and an excellent electron mobility of ≈96 cm2 V−1 s−1, surpassing that of pristine printed 2D In2O3 and many other reported 2D semiconductors. UV-detectors based on annealed 2D In2O3 also benefit from this process step, with the photoresponsivity reaching 5.2 × 104 and 9.4 × 103 A W−1 at the wavelengths of 285 and 365 nm, respectively. These values are an order of magnitude higher than for as-synthesized 2D In2O3. Utilizing transmission electron microscopy with in situ annealing, it is demonstrated that the improvement in device performances is due to nanostructural changes within the oxide layers during annealing process. This work highlights a facile and ambient air compatible method for fabricating high-quality semiconducting oxides, which will find application in emerging transparent electronics and optoelectronics.
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ItemNo Preview AvailableUltrasonics in polymer science: applications and challenges(Elsevier BV, 2023-07-01)Ultrasonic waves in a liquid media generate both chemical and mechanistic effects that are actively used to perform chemical reactions, polymer synthesis, nanoparticle synthesis, colloids, food processing and so on. The application of sonochemistry in polymer science has been an interesting topic of research in the recent years. Ultrasonication acts as an external stimulus to initiate free radical polymerization (FRP) by the homolysis of the solvent, thereby generating radicals. The recent utilization of high frequency ultrasound (>100 KHz) for polymer synthesis has evoked new interest in the use of sonochemistry in the field of polymer chemistry, especially in chain growth polymerization reactions including reversible-deactivation radical polymerization (RDRP) techniques and novel applications. This review presents the principles of sonochemisty and the fundamental aspects governing the cavitation process and the radical generation process. A historical overview of the development of ultrasound-assisted polymerization with a focus on chain-growth polymerizations operating under pseudo-“living” conditions including nitroxide-mediated polymerization (NMP), atom transfer radical polymerization (ATRP) and reversible addition–fragmentation chain transfer (RAFT) polymerization is provided. The utilization of ultrasound in polymer applications such as hydrogels, biomedical nanostructures, drug delivery, nanocomposite synthesis is also discussed. Unlike conventional FRP, ultrasound-initiated polymerization does not involve any external toxic chemical initiators, adds temporal control to the polymerization process, offers excellent control over the molecular weight and the microstructure of the final polymers, etc. The ultrasound assisted polymerization is a novel, clean and green technology, which can be investigated further by coupling with thermo-, mechano- or photochemical stimuli or flow chemistry. It has the potential to be scaled up into an industrial process.
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ItemNo Preview AvailableMaximise Your Research Outcomes – Engage the Expertise Available at the MCFP( 2023-03-07)Oral presentation
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ItemNo Preview AvailableAdvanced fluorescence imaging with Zeiss Elyra( 2022-05-19)Oral presentation, MCFP 2022 Webinar Series
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ItemNo Preview AvailableEGCG-Infused Lipid Nanoparticles for Protein Delivery( 2022-11-28)Oral presentation, Internal Meeting
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ItemNo Preview AvailablePolyphenol Nanoparticles for Therapeutic Delivery( 2023-03-10)Oral presentation at HIV Program Grant Annual Meeting
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ItemNo Preview AvailableThe effectiveness of dietary polyphenols in obesity management: A systematic review and meta-analysis of human clinical trials(ELSEVIER SCI LTD, 2023-03-15)Dietary polyphenols have been postulated to be effective in preventing obesity through various multitargeted mechanisms of weight loss. A meta-analysis of recent clinical trials was carried out to evaluate the effectiveness of polyphenols in obesity management in adults through assessing obesity-related anthropometric measures. Forty-four articles with 40 randomised clinical trials published between 2010 and 2021 met the eligibility trial criteria. Pooled results showed that polyphenols had a statistically significant reduction in body weight, body mass index and waist circumference. No significant lowering effect on body fat percentage was reported. Subgroup analysis suggested that polyphenol intake significantly changed anthropometric parameters in subjects aged <50 years, in Asian populations, in patients with obesity-related health issues, for periods of ≥ 3 months, and at dosages of <220 mg d-1. Overall, dietary polyphenols show promise in the prevention and management of obesity for certain adults.
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ItemDirect synthesis of amorphous coordination polymers and metal-organic frameworks(NATURE PORTFOLIO, 2023-03-06)Coordination polymers (CPs) and their subset, metal-organic frameworks (MOFs), can have porous structures and hybrid physicochemical properties that are useful for diverse applications. Although crystalline CPs and MOFs have received the most attention to date, their amorphous states are of growing interest as they can be directly synthesized under mild conditions. Directly synthesized amorphous CPs (aCPs) can be constructed from a wider range of metals and ligands than their crystalline and crystal-derived counterparts and demonstrate numerous unique material properties, such as higher mechanical robustness, increased stability and greater processability. This Review examines methods for the direct synthesis of aCPs and amorphous MOFs, as well as their properties and characterization routes, and offers a perspective on the opportunities for the widespread adoption of directly synthesized aCPs.