Viscoelastic Effects of Silicone Gels at the Micro- and Nanoscale

AbstractThere has been an increased use of silicone gel for applications such as cell traction force measurements as well as lab- and organ-on-chip systems. However, silicone gel is a viscoelastic material which tends to undergo non-elastic deformation and displays time-dependent and strain rate-dependent responses. Here, we evaluated the mechanical responses of two types of commonly used silicone gels, Sylgard-184 and CY52-276, when subjected to nanoNewton force and micrometer displacement length scales. Using different mechanical characterization tools and theoretical models, we characterized and quantified the viscoelastic parameters of these substrates. Our experimental results showed that silicone substrates with high stiffness and elasticity and negligible strain rate-dependency and creep responses will be most suited for use at the nanoNewton force and micrometer displacement length scales such as that encountered in cell traction force assays

Nanotechnology in peripheral nerve repair and reconstruction

The recent progress in biomaterials science and development of tubular conduits (TCs) still fails in solving the current challenges in the treatment of peripheral nerve injuries (PNIs), in particular when disease-related and long-gap defects need to be addressed. Nanotechnology-based therapies that seemed unreachable in the past are now being considered for the repair and reconstruction of PNIs, having the power to deliver bioactive molecules in a controlled manner, to tune cellular behavior, and ultimately guide tissue regeneration in an effective manner. It also offers opportunities in the imaging field, with a degree of precision never achieved before, which is useful for diagnosis, surgery and in the patientâ s follow-up. Nanotechnology approaches applied in PNI regeneration and theranostics, emphasizing the ones that are moving from the lab bench to the clinics, are herein overviewed.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the financial support provided to Joaquim M. Oliveira (IF/01285/2015) and Joana Silva-Correia (IF/00115/2015) under the program “Investigador FCT”.info:eu-repo/semantics/publishedVersio

Disposable sensors in diagnostics, food and environmental monitoring

Disposable sensors are low‐cost and easy‐to‐use sensing devices intended for short‐term or rapid single‐point measurements. The growing demand for fast, accessible, and reliable information in a vastly connected world makes disposable sensors increasingly important. The areas of application for such devices are numerous, ranging from pharmaceutical, agricultural, environmental, forensic, and food sciences to wearables and clinical diagnostics, especially in resource‐limited settings. The capabilities of disposable sensors can extend beyond measuring traditional physical quantities (for example, temperature or pressure); they can provide critical chemical and biological information (chemo‐ and biosensors) that can be digitized and made available to users and centralized/decentralized facilities for data storage, remotely. These features could pave the way for new classes of low‐cost systems for health, food, and environmental monitoring that can democratize sensing across the globe. Here, a brief insight into the materials and basics of sensors (methods of transduction, molecular recognition, and amplification) is provided followed by a comprehensive and critical overview of the disposable sensors currently used for medical diagnostics, food, and environmental analysis. Finally, views on how the field of disposable sensing devices will continue its evolution are discussed, including the future trends, challenges, and opportunities

Do biomedical engineers dream of graphene sheets?

During the past few years, graphene has outstandingly emerged as a key nanomaterial for boosting the performance of commercial, industrial and scientific related technologies. The popularity of this novel nanomaterial in biomedical engineering is due to its excellent biological, electronic, optical and thermal properties that, as a whole, surpasses the features of commonly used biomaterials and consequently open a wide range of applications so far within the reach of science fiction. In this minireview, the potential of graphene and its based materials in the expanding biomedical field is highlighted with focus on groundbreaking diagnostic, monitoring and therapeutic strategies. Some of the major challenges related to the synthesis and safety of graphene-based materials are also briefly discussed because of their critical importance in bringing this class of carbon materials closer to the clinic.publishe

NANO-BIO INTERACTIONS OF GRAPHENE OXIDE WITH BLOOD-RELATED ENTITIES AND THEIR APPLICATIONS IN HEALTH AND DISEASE

Ph.DDOCTOR OF PHILOSOPH

Synthesis, optical properties, and chemical-biological sensing applications of one-dimensional inorganic semiconductor nanowires

10.1016/j.pmatsci.2013.01.001Progress in Materials Science585705-748PRMS

Bioorthogonal reactions and AIEgen-based metabolically engineered theranostic systems

10.1016/j.chempr.2023.04.004Chem982078-209

Enhancing the Theranostic Performance of Organic Photosensitizers with Aggregation-Induced Emission

10.1021/accountsmr.2c00039ACCOUNTS OF MATERIALS RESEARCH3