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Creators/Authors contains: "Bhattarai, Narayan"

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  1. Abstract Medical devices play a crucial role in modern healthcare, providing innovative solutions for diagnosing, preventing, monitoring, and treating ailments. Artificial Intelligence is transforming the field of medical devices, offering unprecedented opportunities through diagnostic accuracy, personalized treatment plans, and enhancing patient outcomes. This review outlines the applications of artificial intelligence-based medical devices in healthcare specialties, especially in dentistry, medical imaging, ophthalmology, mental health, autism spectrum disorder diagnosis, oncology, and general medicine. Specifically, the review highlights advancements such as improved diagnostic accuracy, tailored treatment planning, and enhanced clinical outcomes in the above-mentioned applications. Regulatory approval remains a key issue, where medical devices must be approved or cleared by the United States Food and Drug Administration to establish their safety and efficacy. The regulatory guidance pathway for artificial intelligence-based medical devices is presented and moreover the critical technical, ethical, and implementation challenges that must be addressed for large-scale adoption are discussed. The review concludes that the intersection of artificial intelligence with the medical device domain and internet-enabled or enhanced technology, such as biotechnology, nanotechnology, and personalized therapeutics, enables an enormous opportunity to accelerate customized and patient-centered care. By evaluating these advancements and challenges, the study aims to present insights into the future trajectory of smart medical technologies and their role in advancing personalized, patient-centered care. 
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  2. This study introduces alginate-chitin nanofibril hydrogel microcapsules, crosslinked with calcium and ferric ions, as robust 3D structures that have promising uses in multiple biomedical applications. 
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    Free, publicly-accessible full text available April 16, 2026
  3. Microcapsules provide a microenvironment by improving the protection and delivery of cells and drugs to specific tissue areas, promoting cell integration and tissue regeneration. Effective microcapsules must not only be permeable for micronutrient diffusion but mechanically stable. Alginate hydrogel is one of the commonly used biomaterials for fabricating microcapsules due to its gel-forming ability and low toxicity. However, its mechanical instability, inertness, and excessive porosity have impeded its use. Embedding nanofibrils in the alginate hydrogel microcapsules improves their biological and mechanical properties. In this research, electrospun composite nanofibers of PCL–gelatin (PG) were first fabricated, characterized, and cryoground. The filtered and cryoground powder solution was mixed with the alginate solution and through electrospray, fabricated into microcapsules. Parameters such as flow rate, voltage, and hydrogel composition, which are critical in the electrostatic encapsulation process, were optimized. The microcapsules were further immersed in different solvent environments (DI water, complete media, and PBS), which were observed and compared for their morphology, size distribution, and mechanical stability properties. The average diameters of the PG nanofibers ranged between 0.2 and 2 μm, with an average porosity between 58 and 73%. The average size of the microcapsules varied between 300 and 900 μm, depending on the solvent environment. Overall, results showed an improved alginate 3D hydrogel network suitable for biomedical applications. 
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    Free, publicly-accessible full text available March 1, 2026
  4. Fluorescence is a remarkable property exhibited by many chemical compounds and biomolecules. Fluorescence has revolutionized analytical and biomedical sciences due to its wide-ranging applications in analytical and diagnostic tools of biological and environmental importance. Fluorescent molecules are frequently employed in drug delivery, optical sensing, cellular imaging, and biomarker discovery. Cancer is a global challenge and fluorescence agents can function as diagnostic as well as monitoring tools, both during early tumor progression and treatment monitoring. Many fluorescent compounds can be found in their natural form, but recent developments in synthetic chemistry and molecular biology have allowed us to synthesize and tune fluorescent molecules that would not otherwise exist in nature. Naturally derived fluorescent compounds are generally more biocompatible and environmentally friendly. They can also be modified in cost-effective and target-specific ways with the help of synthetic tools. Understanding their unique chemical structures and photophysical properties is key to harnessing their full potential in biomedical and analytical research. As drug discovery efforts require the rigorous characterization of pharmacokinetics and pharmacodynamics, fluorescence-based detection accelerates the understanding of drug interactions via in vitro and in vivo assays. Herein, we provide a review of natural products and synthetic analogs that exhibit fluorescence properties and can be used as probes, detailing their photophysical properties. We have also provided some insights into the relationships between chemical structures and fluorescent properties. Finally, we have discussed the applications of fluorescent compounds in biomedical science, mainly in the study of tumor and cancer cells and analytical research, highlighting their pivotal role in advancing drug delivery, biomarkers, cell imaging, biosensing technologies, and as targeting ligands in the diagnosis of tumors. 
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    Free, publicly-accessible full text available December 1, 2025
  5. Abstract Zinc oxide nanoparticles (ZnO NPs) are versatile and promising, with diverse applications in environmental remediation, nanomedicine, cancer treatment, and drug delivery. In this study, ZnO NPs were synthesized utilizing extracts derived fromAcacia catechu, Artemisia vulgaris, andCynodon dactylon. The synthesized ZnO NPs showed an Ultraviolet–visible spectrum at 370 nm, and X-ray diffraction analysis indicated the hexagonal wurtzite framework with the average crystallite size of 15.07 nm, 16.98 nm, and 18.97 nm for nanoparticles synthesized utilizingA. catechu, A. vulgaris,andC. dactylonrespectively. Scanning electron microscopy (SEM) demonstrated spherical surface morphology with average diameters of 18.5 nm, 17.82 nm, and 17.83 nm for ZnO NPs prepared fromA. catechu, A. vulgaris, andC. dactylon,respectively. Furthermore, ZnO NPs tested againstStaphylococcus aureus, Kocuria rhizophila, Klebsiella pneumonia,andShigella sonneidemonstrated a zone of inhibition of 8 to 14 mm. The cell viability and cytotoxicity effects of ZnO NPs were studied on NIH-3T3 mouse fibroblast cells treated with different concentrations (5 μg/mL, 10 μg/mL, and 50 μg/mL). The results showed biocompatibility of all samples, except with higher doses causing cell death. In conclusion, the ZnO NPs synthesized through plant-mediated technique showed promise for potential utilization in various biomedical applications in the future. 
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  6. Three-dimensional (3D) printing was utilized for the fabrication of a composite scaffold of poly(ε-caprolactone) (PCL) and calcium magnesium phosphate (CMP) bioceramics for bone tissue engineering application. Four groups of scaffolds, that is, PMC-0, PMC-5, PMC-10, and PMC-15, were fabricated using a custom 3D printer. Rheology analysis, surface morphology, and wettability of the scaffolds were characterized. The PMC-0 scaffolds displayed a smoother surface texture and an increase in the ceramic content of the composite scaffolds exhibited a rougher structure. The hydrophilicity of the composite scaffold was significantly enhanced compared to the control PMC-0. The effect of ceramic content on the bioactivity of fibroblast NIH/3T3 cells in the composite scaffold was investigated. Cell viability and toxicity studies were evaluated by comparing results from lactate dehydrogenase (LDH) and Alamar Blue (AB) colorimetric assays, respectively. The live-dead cell assay illustrated the biocompatibility of the tested samples with more than 100% of live cells on day 3 compared to the control one. The LDH release indicated that the composite scaffolds improved cell attachment and proliferation. In this research, the fabrication of a customized composite 3D scaffold not only mimics the rough textured architecture, porosity, and chemical composition of natural bone tissue matrices but also serves as a source for soluble ions of calcium and magnesium that are favorable for bone cells to grow. These 3D-printed scaffolds thus provide a desirable microenvironment to facilitate biomineralization and could be a new effective approach for preparing constructs suitable for bone tissue engineering. 
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  7. Electrospun fibrous scaffolds made from polymers such as polycaprolactone (PCL) have been used in drug delivery and tissue engineering for their viscoelasticity, biocompatibility, biodegradability, and tunability. Hydrophobicity and the prolonged degradation of PCL causes inhibition of the natural tissue-remodeling processes. Poliglecaprone (PGC), which consists of PCL and Poly (glycolic acid) (PGA), has better mechanical properties and a shorter degradation time compared to PCL. A blend between PCL and PGC called PPG can give enhanced shared properties for biomedical applications. In this study, we fabricated a blend of PCL and PGC nanofibrous scaffold (PPG) at different ratios of PGC utilizing electrospinning. We studied the physicochemical and biological properties, such as morphology, crystallinity, surface wettability, degradation, surface functionalization, and cellular compatibility. All PPG scaffolds exhibited good uniformity in fiber morphology and improved mechanical properties. The surface wettability and degradation studies confirmed that increasing PGC in the PPG composites increased hydrophilicity and scaffold degradation respectively. Cell viability and cytotoxicity results showed that the scaffold with PGC was more viable and less toxic than the PCL-only scaffolds. PPG fibers were successfully coated with polydopamine (PDA) and collagen to improve degradation, biocompatibility, and bioactivity. The nanofibrous scaffolds synthesized in this study can be utilized for tissue engineering applications such as for regeneration of human articular cartilage regeneration and soft bones. 
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  8. An engineered 3D architectural network of the biopolymeric hydrogel can mimic the native cell environment that promotes cell infiltration and growth. Among several bio-fabricated hydrogel structures, core–shell microcapsules inherit the potential of cell encapsulation to ensure the growth and transport of cells and cell metabolites. Herein, a co-axial electrostatic encapsulation strategy is used to create and encapsulate the cells into chitin nanofibrils integrated alginate hydrogel microcapsules. Three parameters that are critical in the electrostatic encapsulation process, hydrogel composition, flow rate, and voltage were optimized. The physicochemical characterization including structure, size, and stability of the core–shell microcapsules was analyzed by scanning electron microscope (SEM), FTIR, and mechanical tests. The cellular responses of the core–shell microcapsules were evaluated through in vitro cell studies by encapsulating NIH/3T3 fibroblast cells. Notably, the bioactive microcapsule showed that the cell viability was found excellent for more than 2 weeks. Thus, the results of this core–shell microcapsule showed a promising approach to creating 3D hydrogel networks suitable for different biomedical applications such as in vitro tissue models for toxicity studies, wound healing, and tissue repair. 
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