Chitosan functionalized gold-nickel bimetallic magnetic nanomachines for motion-based deoxyribonucleic acid recognition

Graphene Quantum Dot-Based Gold-Nickel Micromotors for Sensitive Detection of Ferric Ions

The development of nano and micromotors has revolutionized the field of nanotechnology, offering innovative solutions for applications in biomedical engineering, environmental monitoring, and chemical sensing. Among these nano/micromotors, graphene quantum dot (GQD)-based micromotors have gained significant attention due to their unique optical and electronic properties. This study presents the synthesis and characterization of novel graphene quantum dot-based gold-nickel (GQD-Au-Ni) micromotors. These micromotors were synthesized using an electrochemical template deposition process, allowing precise control over their composition and structure. The GQD-Au-Ni micromotors exhibit multifunctionality, employing fluorometric, magnetic, and electrochemical methods for the selective and sensitive detection of ferric ions (Fe³⁺), with a remarkable limit of detection (LOD). The study highlights the potential of these micromotors in environmental monitoring paving the way for future research into multifunctional micromotors for a wide range of applications. The findings underscore the promise of GQD-based systems in advancing sensor technology and addressing critical challenges in environmental and health monitoring.

Ultrasound meets nanomedicine: towards disease treatment and medical imaging

As a kind of mechanical wave, ultrasound has been widely employed in the biomedical field due to its superiors of deep tissue penetration, non-destructiveness and non-toxicity. In this review, we highlight current progress and prospects in using ultrasound as a powerful tool for disease treatment and medical imaging, including (1) ultrasound as energy input for driving nano/micromotor in drug delivery, this part first introduces the synthesis and motion behavior of nano/micromotors, then reviews the small molecular and macromolecular compounds that the nano/micromotors are delivering; (2) sonosensitive nanomaterials for disease therapy, the sonodynamic, sonopiezoelectric, sonothermal, and sonomechanical therapy will all be covered; (3) ultrasound as a non-invasive technique for nano/micromotor tracking or medical imaging; (4) the sonoporation of nano/microbubble. Future challenges in using ultrasound for disease treatment or medical imaging will also be described in the conclusion part.

Modified Au:Fe-Ni magnetic micromotors improve drug delivery and diagnosis in MCF-7 cells and spheroids

Nano/micromotors hold immense potential for revolutionizing drug delivery and detection systems, especially in the realm of cancer diagnosis and treatment, owing to their distinctive features, including precise propulsion, maneuverability, and meticulously designed surface modifications. In this study, we explore the capabilities of modified and magnetically driven micromotors as active drug delivery systems within 2D and 3D cell culture environments and cancer diagnosis. We synthesized gold (Au) and iron-nickel (Fe-Ni) metallic-based magnetic micromotors (Au:Fe-Ni MMs) through electrochemical methods, equipping them with functionalities for controlled doxorubicin (DOX) release and cancer cell recognition. In 2D and spheroids of MCF-7 adenocarcinoma cells, the Au segment of these micromotors was utilized to help DOX loading through poly(sodium-4-styrenesulfonate) (PSS) functionalization, and the attachment of antiHER2 antibodies for specific recognition. This innovative approach enabled controlled drug release within the cancerous microenvironment, coupled with magnetic (Fe-Ni) propulsion for biocompatible drug delivery to MCF-7 cells. Furthermore, antiHER2 immobilized Au:Fe-Ni MMs effectively interacted with receptors, capitalizing on the overexpression of HER2 antigens on MCF-7 cells. Encouraging outcomes were observed, particularly in spheroid models, underscoring the remarkable potential of these multifunctional micromotors for advancing intelligent drug delivery methodologies and diagnostic purposes.

Biocompatible polymer-based micro/nanorobots for theranostic translational applications

Recently, micro/nanorobots (MNRs) with self-propulsion have emerged as a promising smart platform for diagnostic, therapeutic and theranostic applications. Especially, polymer-based MNRs have attracted huge attention due to their inherent biocompatibility and versatility, making them actively explored for various medical applications. As the translation of MNRs from laboratory to clinical settings is imperative, the use of appropriate polymers for MNRs is a key strategy, which can prompt the advancement of MNRs to the next phase. In this review, we describe the multifunctional versatile polymers in MNRs, and their biodegradability, motion control, cargo loading and release, adhesion, and other characteristics. After that, we review the theranostic applications of polymer-based MNRs to bioimaging, biosensing, drug delivery, and tissue engineering. Furthermore, we address the challenges that must be overcome to facilitate the translational development of polymeric MNRs with future perspectives. This review would provide valuable insights into the state-of-the-art technologies associated with polymeric MNRs and contribute to their progression for further clinical development.

Advancements in artificial micro/nanomotors for nucleic acid biosensing: a review of recent progress

Artificial micro/nanomotors represent a class of well-designed tools that exhibit dynamic motion and remote-control capabilities, endowing them with the capacity to perform complex tasks at the micro/nanoscale. Their utilization in nucleic acid biosensing has been paid significant attention, owing to their ability to facilitate targeted delivery of detection probes to designated sites and enhance hybridization between detection probes and target nucleic acids, thereby improving the sensitivity and specificity of biosensing. Within this comprehensive overview, we elucidate the advancement of nucleic acid biosensing through the integration of micro/nanomotors over the past decade. In particular, we provide an in-depth exploration of the diverse applications of micro/nanomotors in nucleic acid biosensing, including fluorescence recovery-based biosensing, velocity change-based biosensing, and aggregation-enhanced biosensing. Additionally, we outline the remaining challenges that impede the practical application of artificial micro/nanomotors in nucleic acid detection, and offer personal insights into prospective avenues for future development. By overcoming these obstacles, we anticipate that artificial micro/nanomotors will revolutionize conventional nucleic acid detection methodologies, providing enhanced sensitivity and reduced diagnostic timeframes, thereby facilitating more effective disease diagnosis.

Biocompatible micromotors for biosensing

Micro/nanomotors are nanoscale devices that have been explored in various fields, such as drug delivery, environmental remediation, or biosensing and diagnosis. The use of micro/nanomotors has grown considerably over the past few years, partially because of the advantages that they offer in the development of new conceptual avenues in biosensing. This is due to their propulsion and intermixing in solution compared with their respective static forms, which enables motion-based detection methods and/or decreases bioassay time. This review focuses on the impacts of micro/nanomotors on biosensing research in the last 2 years. An overview of designs for bioreceptor attachment to micro/nanomotors is given. Recent developments have focused on chemically propelled micromotors using external fuels, commonly hydrogen peroxide. However, the associated fuel toxicity and inconvenience of use in relevant biological samples such as blood have prompted researchers to explore new micro/nanomotor biosensing approaches based on biocompatible propulsion sources such as magnetic or ultrasound fields. The main advances in biocompatible propulsion sources for micro/nanomotors as novel biosensing platforms are discussed and grouped by their propulsion-driven forces. The relevant analytical applications are discussed and representatively illustrated. Moreover, envisioning future biosensing applications, the principal advantages of micro/nanomotor synthesis using biocompatible and biodegradable materials are given. The review concludes with a realistic drawing on the present and future perspectives.