Longyi Chen

The interaction of chemicals, nanoparticles, and circulating cells with the endothelium depends on the magnitude of the mechanical shear produced by the flow of blood. When simulating those interactions with microphysiological systems (MPSs), it is critical to reproduce those shear conditions faithfully. For example, unidirectional flow of a specific magnitude keeps the endothelium healthy with normal barrier tissue function, while bidirectional flow mimics disease conditions with compromised barrier function. Additionally, in MPS, recirculating fluid may be necessary to retain tissue-derived factors and metabolites. However, existing MPS designs struggle to achieve medium recirculation of small volumes of liquid with precise flow control. Here, we present an MPS design that is highly versatile and overcomes this limitation. We demonstrate how the device can produce a wide range of fluidic flow rates that can accommodate both low shear conditions suitable for tissues that typically are only exposed to interstitial flow and high shear conditions suitable for barrier tissues that experience blood flow. We demonstrate the device’s functionality by culturing human umbilical vein endothelial cells (HUVEC) and confirming their flow-aligned morphology through immunostaining of the adherens junction protein (VE-cadherin) and actin filaments. Furthermore, we present a mathematical model that can be used to calculate operating parameters for culturing any tissue under optimum conditions. We also discuss how the device can be adjusted to recirculate liquid volumes ranging from 100 µL to 5 mL. This versatile system holds promise for commercial applications, including the investigation of expensive compounds that are limited to very small volume samples such as rare cells (e.g., circulating tumor cells) or engineered therapeutic cells with barrier tissues. By offering precise control over a wide range of flow conditions with medium recirculation of small liquid volumes, our device addresses a critical gap in current MPS technology.

Peripheral nerve injury accounts for 2-5% of all trauma admissions worldwide and is a significant clinical challenge. In this research, a novel nerve guidance conduit biomaterial based on a tungsten oxide nanomaterial-decorated oxidized bacterial cellulose hydrogel was developed for repairing sciatic nerve injury. The bacterial cellulose was oxidized by sodium periodate, and aldehyde functional groups were introduced to enhance its reactivity and biocompatibility. At the same time, the incorporation of the tungsten oxide nanomaterial not only significantly improved its antibacterial properties but also rendered the material antioxidant. The functional recovery of the sciatic nerve in the rat transection model was assessed by the sciatic functional index, gastrocnemius histological analysis, and nerve histological analysis. This bacterial cellulose/tungsten oxide nanoparticle hybrid hydrogel biocomposite can effectively promote sciatic axon regeneration, Schwann cell activity, and nerve function recovery. This novel biocomposite provides a new therapeutic strategy for the repair of a sciatic nerve injury.

The realization of the oriented immobilization of antibodies onto the surfaces of solid or nanometal particles constitutes a significant approach for enhancing the performance of electrochemical immunosensors. In light of the research findings of predecessors, this review showcases several immobilization methods, categorizing them into covalent binding pathways, bioaffinity techniques, and other binding modalities for elaboration. Emphasis is placed on expounding the binding sites, binding mechanisms, as well as the merits and drawbacks of binding techniques such as those involving disulfide bonds, glycan chains, protein A, G, and DNA.

Elaeagnus angustifolia gum offers a good polysaccharide biomass source for producing porous biochar. The incorporation of CoO cracked nanoplate and the biochar gave a promising application in analysis of clinical urine.

A novel Zn-doped Fe ₃ O ₄ nanoparticle@N, S and P doped Elaeagnus angustifolia gum derived carbon hybrid electrocatalyst was prepared, characterized and applied for electrochemical sensing of acetaminophen covering urinary physiological concentration.

Acetaminophen (N-acetyl-p-aminophenol, APAP) is regularly used for antipyretic and analgesic purposes. Overdose or long-term exposure to APAP could lead to liver damage and hepatotoxicity. In this study, the approach of enhanced electrochemical detection of APAP by nanostructured biomass carbon/silver was developed. Porous biomass carbon derived from Elaeagnus Angustifolia gum was prepared by pyrolysis with co-doping of electron-rich elements of nitrogen, sulfur, and phosphorus. The electrodeposition of silver onto a glassy carbon electrode modified with porous carbon could enhance the sensing signal towards APAP. Two linear ranges from 61 nM to 500 μM were achieved with a limit of detection of 33 nM. The developed GCE sensor has good anti-interference, stability, reproducibility, and human urine sample analysis performance. The silver-enhanced biomass carbon GCE sensor extends the application of biomass carbon, and its facile preparation approach could be used in constructing disposable sensing chips in the future.