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The Fitzpatrick Skin Phototype Classification (FSPC) scale is widely used to categorize skin types but has limitations such as the underrepresentation of darker skin phototypes, low classification resolution, and subjectivity. These limitations may contribute to dermatological care disparities in patients with darker skin phototypes, including the misdiagnosis of wound healing progression and escalated dermatological disease severity. This study introduces (1) an optical sensor measuring reflected light across 410–940 nm, (2) an unsupervised K-means algorithm for skin phototype classification using broadband optical data, and (3) methods to optimize classification across the Near-ultraviolet-A, Visible, and Near-infrared spectra. The differentiation capability of the algorithm was compared to human assessment based on FSPC in a diverse participant population (n = 30) spanning an even distribution of the full FSPC scale. The FSPC assessment distinguished between light and dark skin phototypes (e.g., FSPC I vs. VI) at 560, 585, and 645 nm but struggled with more similar phototypes (e.g., I vs. II). The K-means algorithm demonstrated stronger differentiation across a broader range of wavelengths, resulting in better classification resolution and supporting its use as a quantifiable and reproducible method for skin type classification. We also demonstrate the optimization of this method for specific bandwidths of interest and their associated clinical implications. [ABSTRACT FROM AUTHOR]

Interfacial fibrosis is known to dramatically decrease the lifespan, stability, and function of biomedical implants and bone-anchored prosthetics. Bioactive coatings aimed at mitigating fibrous adhesions are one of the approaches to alleviate the problem. In this paper, we are developing a bioactive coating based upon a magnetoelastic (ME) material that vibrates in response to an ac magnetic field. In order to establish these coatings for this purpose, the ME material was first rendered bioactive through the sequential addition of polyurethane and chitosan thin films. Indirect live/dead assays were performed showing increased cell viability for polyurethane and chitosan-coated sensors compared to the uncoated controls. Direct adhesion experiments were performed to test the response of fibroblasts cultured on static and vibrated ME materials. Results showed cells adherent to static but not vibrated coatings. Detached cells showed no viability loss compared to controls. The finding that submicrometer ME vibrations can prevent cell adhesion in vitro without inducing cell death suggests the potential of these coatings to effectively control interfacial fibrosis. Future work will address the effect of vibrations on cell morphology and local gene expression in vitro, as well as fibrous tissue formation in vivo. [ABSTRACT FROM PUBLISHER]

Advances in cell and tissue therapies are slow to be implemented in the clinic due to the limited standardization of safety and quality control techniques. Current approaches for monitoring cell and tissue manufacturing processes are time and labor intensive, costly, and lack commercial scalability. One method to improving in vitro manufacturing processes includes utilizing the coupled magnetic and mechanical properties of magnetoelastic (ME) materials as passive and wireless sensors and actuators. Specifically, ME materials can be used in quantifying cell adhesion, detecting contamination, measuring biomarkers, providing biomechanical stimulus, and enabling cell detachment in bioreactors. This review outlines critical design considerations for ME systems and summarizes recent developments in utilizing ME materials for sensing and actuation in cell and tissue engineering. [ABSTRACT FROM AUTHOR]

As a prominent concern regarding implantable devices, eliminating the threat of opportunistic bacterial infection represents a significant benefit to both patient health and device function. Current treatment options focus on chemical approaches to negate bacterial adhesion, however, these methods are in some ways limited. The scope of this study was to assess the efficacy of a novel means of modulating bacterial adhesion through the application of vibrations using magnetoelastic materials. Magnetoelastic materials possess unique magnetostrictive property that can convert a magnetic field stimulus into a mechanical deformation. In vitro experiments demonstrated that vibrational loads generated by the magnetoelastic materials significantly reduced the number of adherent bacteria on samples exposed to Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus suspensions. These experiments demonstrate that vibrational loads from magnetoelastic materials can be used as a post-deployment activated means to deter bacterial adhesion and device infection.

This paper describes the fabrication of a wireless, passive sensor based on aninductive-capacitive resonant circuit, and its application for in situ monitoring of thequality of dry, packaged food such as cereals, and fried and baked snacks. The sensor ismade of a planar inductor and capacitor printed on a paper substrate. To monitor foodquality, the sensor is embedded inside the food package by adhering it to the package'sinner wall; its response is remotely detected through a coil connected to a sensor reader. Asfood quality degrades due to increasing humidity inside the package, the paper substrateabsorbs water vapor, changing the capacitor's capacitance and the sensor's resonantfrequency. Therefore, the taste quality of the packaged food can be indirectly determined bymeasuring the change in the sensor's resonant frequency. The novelty of this sensortechnology is its wireless and passive nature, which allows in situ determination of foodquality. In addition, the simple fabrication process and inexpensive sensor material ensure alow sensor cost, thus making this technology economically viable.