With the development of regenerative medicine, tissue repair at the molecular, cellular, tissue, and organ level has seen continuous improvements over traditional techniques. As the core of tissue repair, seed cells are widely used in various fields of regenerative medicine. However, their use is still associated with problems such as decreased cell survival and regeneration capacity after transplantation, immune rejection, and ethical concerns. Therefore, it is difficult to universally and safely apply stem cell banks for regenerative medicine. The paracrine effects of cells, especially secretion of exosomes, play vital roles in cell communication, immune response, angiogenesis, scar formation, tissue repair, and other biological functions. Exosomes are a type of nanoscale extracellular vesicle that contain biologically active molecules such as RNA and proteins; therefore, exosomes can replicate the functions of their parental cells. Meanwhile, exosomes can be used as nanocarriers to deliver active factors or small molecules to promote tissue repair. Preclinical studies of exosomes in tissue engineering and regenerative medicine have been carried in the fields of bone/cartilage repair, nerve regeneration, liver and kidney regeneration, skin repair, vascular tissue regeneration, etc. This review introduces exosomes from the aspects of biogenesis, composition, identification, and isolation, and focuses on the development status of scaffold materials for exosome delivery. In addition, we highlight examples of exosome-laden scaffolds for preclinical applications in tissue repair. We look forward to the broad application prospects of exosome-laden scaffolds.

Oxygen vacancies implantation is an efficient way to adjust the physical and chemical properties of metal oxide nanomaterials to meet the requirements for particular applications. Through reasonable defects design, oxygen-deficient metal oxides with excellent optical and electrical properties are widely applied for environmental protection and energy uses. This review discusses recent advances in synthetic approaches of oxygen-deficient metal oxides and their applications in photocatalysis, electrocatalysis, and energy storage devices. The perspectives of oxygen-deficient metal oxides for increased energy demand and environmental sustainability are also examined. Open image in new window

Photothermal properties of GNSs and GNRs are compared both experimentally and theoretically, and results show that GNSs exhibit a higher molar heating rate than GNRs.

Three-dimensional (3D) bioprinting is an emerging technology based on 3D digital imaging technology and multi-level continuous printing. The precise positioning of biological materials, seed cells, and biological factors, known as “additive biomanufacturing”, can provide personalized therapy strategies in regenerative medicine. Over the last two decades, 3D bioprinting hydrogels have significantly advanced the field of cartilage and bone tissue engineering. This article reviews the development of 3D bioprinting and its application in cartilage tissue engineering, followed by a discussion of the current challenges and prospects for 3D bioprinting. This review presents foundational information on the future optimization of the design and manufacturing process of 3D additive biomanufacturing.

In this paper, we present a stable silver-based surface plasmon resonance (SPR) sensor using a self-assembled monolayer (SAM) as a protection layer and investigated its efficiency in water and 0.01 M phosphate buffered saline (PBS). By simulation, silver-based SPR sensor has a better performance in field enhancement and penetration depth than that of a gold-based SPR sensor, which are 5 and 1.4 times, respectively. To overcome the instability of the bare silver film and investigate the efficiency of the protected layer, the SAM of 11-mercapto-1-undecanol (MUD) was used as a protection layer. Stability experiment results show that the protected silver film exhibited excellent stability either in pure water or 0.01 M PBS buffer. The sensitivity of the silver-based SPR sensor was calculated to be 127.26 deg/RIU (refractive index unit), measured with different concentrations of NaCl solutions. Further, a very high refractive resolution for the silver-based SPR sensor was found to be 2.207 × 10⁻⁷ RIU, which reaches the theoretical limit in the wavelength of 632.8 nm for a SPR sensor reported in the literature. Using a mixed SAM of 16-mercaptohexadecanoic acid (MHDA) and a MUD layer with a ratio of 1:10, this immunosensor for the rabbit immunoglobulin G (IgG) molecule with a limit of detection as low as 22.516 ng/mL was achieved.

Microfluidic biosensors integrate microfluidic and biosensing technologies to achieve the miniaturization, integration, and automation of disease diagnosis, and show great potential for application in the fields of cancer liquid biopsy, pathogenic bacteria detection, and POCT. This paper reviews the recent advances related to microfluidic biosensors in the field of laboratory medicine, focusing on their applications in the above three areas. In cancer liquid biopsy, microfluidic biosensors facilitate the isolation, enrichment, and detection of tumor markers such as CTCs, ctDNA, miRNA, exosomes, and so on, providing support for early diagnosis, precise treatment, and prognostic assessment. In terms of pathogenic bacteria detection, microfluidic biosensors can achieve the rapid, highly sensitive, and highly specific detection of a variety of pathogenic bacteria, helping disease prevention and control as well as public health safety. Pertaining to the realm of POCT, microfluidic biosensors bring the convenient detection of a variety of diseases, such as tumors, infectious diseases, and chronic diseases, to primary health care. Future microfluidic biosensor research will focus on enhancing detection throughput, lowering costs, innovating new recognition elements and signal transduction methods, integrating artificial intelligence, and broadening applications to include home health care, drug discovery, food safety, and so on.