Wearable Microneedle Patch for Colorimetric Detection of Multiple Signature Biomarkers in vivo Toward Diabetic Diagnosis.

Type 2 diabetes is rapidly emerging as a global public health problem. While blood glucose monitoring has been the primary method of managing diabetes for decades, the increasing global prevalence of the disease suggests that there might be a need to identify additional biomarkers for a more precise early diagnosis. Herein, a microneedle patch based wearable sensor is developed for the purpose of diabetic diagnosis. Utilizing methacrylic acid modified gelatin and polyvinyl alcohol in the fabrication of microneedles has improved their mechanical properties for skin penetration and increased swelling capacity for interstitial fluid extraction, thanks to the double crosslinking mechanism. The fabricated microneedles are further integrated with test paper functionalized with enzyme and dye molecules to detect multiple signature biomarkers of diabetes in vivo through a colorimetric reaction. Such a wearable microneedle patch  holds significant promise for the real-time monitoring of various biomarkers related to chronic diseases and aging.

Ligand Mediation for Tunable and Oxide Suppressed Surface Gold-Decorated Liquid Metal Nanoparticles.

Gallium-based liquid metal systems hold vast potential in materials science. However, maximizing their possibilities is hindered by gallium's native oxide and interfacial functionalization. In this study, small-molecule ligands are adopted as surfactants to modify the surface of eutectic gallium indium (EGaIn) nanoparticles and suppress oxidation. Different p-aniline derivatives are explored. Next, the reduction of chloroanric acid (HAuCl4 ) onto these p-aniline ligand modified EGaIn nanoparticles is investigated to produce gold-decorated EGaIn nanosystems. It is found that by altering the concentrations of HAuCl4 or the p-aniline ligand, the formation of gold nanoparticles (AuNPs) on EGaIn can be manipulated. The reduction of interfacial oxidation and presence of AuNPs enhances electrical conductivity, plasmonic performance, wettability, stability, and photothermal performance of all the p-aniline derivative modified EGaIn. Of these, EGaIn nanoparticles covered with the ligand of p-aminobenzoic acid offer the most evenly distributed AuNPs decoration and perfect elimination of gallium oxides, resulting in the augmented electrical conductivity, and highest wettability suitable for patterning, enhanced aqueous stability, and favorable photothermal properties. The proof-of-concept application in photothermal therapy of cancer cells demonstrates significantly enhanced photothermal conversion performance along with good biocompatibility. Due to such unique characteristics, the developed gold-decorated EGaIn nanodroplets are expected to offer significant potential in precise medicine.

Natural Polymer-Based Hydrogels with Enhanced Mechanical Performances: Preparation, Structure, and Property.

Hydrogels based on natural polymers have bright application prospects in biomedical fields due to their outstanding biocompatibility and biodegradability. However, the poor mechanical performances of pure natural polymer-based hydrogels greatly limit their application prospects. Recently, a variety of strategies has been applied to prepare natural polymer-based hydrogels with enhanced mechanical properties, which generally exhibit stiffening, strengthening, and stretchable behaviors. This article summarizes the recent progress of natural polymer-based hydrogels with enhanced mechanical properties. From a structure point of view, four kinds of hydrogel are reviewed; double network hydrogels, nanocomposite hydrogels, click chemistry-based hydrogels, and supramolecular hydrogels. For each typical hydrogel, its preparation, structure, and mechanical performance are introduced in detail. At the end of this article, the current challenges and future prospects of hydrogels based on natural polymers are discussed and it is pointed out that 3D printing may offer a new platform for the development of natural polymer-based hydrogels.