Since the 20th century, with the development of synthetic chemistry and genome editing technology, biomedical materials have entered a new era, especially in the fields of polymer materials, nanomaterials, metal-organic frameworks, and biosynthetic materials. Biomedical materials are mainly used to diagnose, treat, repair, and replace diseased tissues or organs of living organisms to improve their functionality. As early as ancient times, some natural materials, such as cotton, linen fibers, and horse hair, were used as sutures to heal wounds. In addition, false teeth, noses, and ears have been found in tombs in ancient China and Egypt. Nowadays, with the continuous development of the economy and the elevation of people’s living quality, there is an increased demand for biomedical materials and related technologies, especially for joints, artificial teeth, cardiovascular systems, skin, tissue engineering, and special surgical instruments. Therefore, as driven by intelligent technology, novel biomaterials such as alloys, ceramics, bioglass, carbon-based materials, polymers, and injectable gels are continuously derived with rapidly increasing varieties. Currently, biomedical materials have become one of the fastest developing and most promising directions in the field of materials science, and the biomedical material industry has also become a representative of emerging industries with low energy consumption and high added values. MedMat was born in response to the rapid development of biomedical materials. As a flagship comprehensive open-access journal, MedMat aims to address health challenges such as diagnosis and treatment of major diseases, precise drug delivery, regenerative medicine, tissue engineering, translational medicine, and healthcare. MedMat is expected to achieve milestones in material science and display high academic influence. It is worth mentioning that MedMat will cover a broad scope of topics, including but not limited to medical materials, material-derived therapies, devices and systems for healthcare, biosensors, and bioelectronics, which are specifically designed or engineered for potential medical applications. Specifically, it includes materials for targeted controlled-release vectors, bioelectrodes, stimulus-response materials, integrated diagnosis and treatment systems, smart sensors, and implantable/wearable biomedical devices. MedMat is a comprehensive and cross-field journal that is expected to advance the science and technology related to materials, medicine, and devices, as well as improve the quality of life and health of human beings. Welcome global friends and colleagues to contribute your wonderful works to MedMat. Thank you for your support and contribution!

Bioorthogonal chemistry uses abiotic reactions that do not interfere with natural biological processes.[1] The use of catalysts in bioorthogonal chemistry offers the ability to control nonnative reactions inside complex living systems, enabling localized generation of bioactive molecules. This emerging field of bioorthogonal catalysis has been integrated into a wide range of synthetic biochemical reactions, including prodrug activation, protein transformation, and cellular engineering. In antibacterial applications, bioorthogonal catalysis enables the positioning of these catalytic reactions within close proximity of microbes to allow continual production of antimicrobials at high local concentrations. This strategy is both effective and timely in addressing increasingly challenging infections such as bacterial biofilms and intracellular pathogens (Figure 1).[1] Traditional antibiotics fare poorly in these therapies as they often fail to penetrate biofilms and cell membranes at sufficient concentrations necessary to kill microbes.[2,3] The alarming spread of antimicrobial resistance to antibiotics has also significantly reduced their efficacy toward recalcitrant infections.[4] Additionally, a lack of novel antibiotics in the discovery pipeline worsens the ongoing crisis. Consequently, recent developments in bioorthogonal catalytic activation of antibiotic prodrugs provide a potential solution to both resistance development and access to bacteria (Figure 1). These catalytic reactions also offer chemical tools for utilizing existing antibiotics more effectively by increasing their production at infection sites.

Programmed cell death (PCD) is defined as regulated cell death controlled by an intracellular program. While apoptosis was once thought to be the only kind of PCD, current understanding has expanded to include other forms such as pyroptosis, autophagy, and necroptosis. These processes, especially apoptosis and necroptosis, serve as natural defenses that restrict cancer cells from surviving and disseminating. However, cancer cells have evolved various strategies to evade PCD, including genetic mutations and epigenetic modifications in key modulators of PCD pathways. With the continuous development of nanotechnology, emerging nanomaterials (NMs) are considered to break through this bottleneck due to their intrinsic physicochemical properties. Especially, new kinds of cell death induced by NMs, such as ferroptosis, cuproptosis, and calcium overload, show gratifying potential in cancer therapy, which is closely linked to the role of metal ions. Additionally, other metal ions-induced cell death such as sodium and zinc have also emerged in an endless stream. Hence, we propose the term “metalloptosis” to describe cell death induced by metal ions and summarize its application in cancer therapy through NMs. This review will delve into the critical design principles for engineering NMs involved in metalloptosis and provide a comprehensive summary of current metal ions-mediated cancer therapies, focusing on nanoplatforms and their mechanisms of action. We hope that this review will provide a new perspective on metal ions-mediated cancer therapy based on nanotechnology.

The energy harvesting technology based on piezoelectricity promises to achieve a self-powered mode for portable medical electronic devices. Piezoelectric materials, as crucial components in electromechanical applications, have extensively been utilized in portable medical electronic devices. Especially, degradable piezoelectric biomaterials have received much attention in the medical field due to their excellent biocompatibility and biosafety. This mini-review mainly summarizes the types and structural characteristics of degradable piezoelectric biomaterials from degradable piezoelectric small-molecule crystals to piezoelectric polymers. Afterward, medical applications are briefly introduced, including energy harvester and sensor, actuator and transducer, and tissue engineering scaffold. Finally, from a material perspective, some challenges currently faced by degradable piezoelectric biomaterials are proposed.

Organic afterglow luminescent probes (OALPs), characterized by their long-lasting luminescence after irradiation (by light, ultrasound, or X-rays) cessation, are pivotal tools in autofluorescence-free optical imaging. They exhibit ultra-low background noise interference, enhancing imaging sensitivity and ensuring clearer, more reliable imaging results. Moreover, they offer deeper tissue penetration compared to traditional optical imaging modalities, providing various information from deep tissues. Recently developed sonoafterglow and radioafterglow further enhance tissue penetration depth. This review outlines 2 design approaches for OALPs: coencapsulation and conjugation, which are derived from their luminescent mechanism. Guided by these strategies, researchers have designed 3 types of OALPs: near-infrared OALPs, responsive OALPs, and ratiometric OALPs. Additionally, we also provided examples of how OALPs are integrated with therapy and applied in the field of cancer theranostics. Finally, we discuss certain challenges encountered in the advancement of the next generation of OALPs, aiming to broaden their scope of applications.