Contraceptive methods based on intrauterine devices (IUD) typically result in women being constantly exposed to either hormones or copper ions. Although it is well known that the pH in vaginal fluids increases from around 3.5 to 7 during intercourse, pH-responsive materials have yet to be explored for controlling the local release of contraceptive agents. Here, we describe the design of an open-source smart IUD able to modulate copper ion release on demand thanks to the integration of pH-sensitive biopolymer-based hydrogels. Both anionic and cationic hydrogels with different release strategies were investigated. In anionic gels, an increase in pH promotes an increase in the diffusion coefficient; while in cationic gels, an alkaline environment results in shrinking, exposing part of the copper wire. Computational simulations were used to verify that gel thickness was appropriate for minimal copper ion leaching at low pH and effective dose release at higher pH. A thin gel coating was integrated into a commercial IUD using a custom 3D printed mold. Copper ion release was investigated at different time points in acid and basic solutions. The results show that both anionic and cationic gels can be used to engineer smart and safer IUDs.
The house dust mite Dermatophagoides pteronyssinus produces major allergens (Der p 1, Der p 2, and Der p 23) that require precise IgE detection for clinical diagnosis. We developed a multiplex digital ELISA using fluorescence-encoded micromagnetic beads (532 nm/638 nm dual-wavelength system) coupled with microfluidics to simultaneously quantify serum IgE against these components, with comprehensive evaluation against the clinical standard UniCAP system. The 532 nm channel measured allergen-specific signals via average brightness increase (ABMB) of enzymatically amplified fluorescence, while 638 nm enabled spectral bead differentiation. Comparative evaluation with UniCAP showed the improved digital ELISA achieved uniform 75.0% sensitivity but variable specificity (42.9%–54.5%) across allergens at the 15.8% ABMB threshold. Sample classification results (Der p 1: 9 positive/6 negative; Der p 2: 7/8; Der p 23: 7/8) demonstrated suboptimal positive predictive values (33.3%–60.0%) versus more favorable negative predictive values (60.0%–85.7%), with likelihood ratios (LR+: 1.31–1.65) and Cohen's κ (0.12–0.25) suggesting limited diagnostic reliability. The automated platform offered 60% reduced sample volume (20 μL vs. 50 μL), multiplex capability, and maintained sensitivity for low-titer samples, representing an efficient screening solution pending specificity enhancement.
Ulcerative colitis (UC) remains a significant therapeutic challenge due to its complex pathogenesis involving oxidative stress, immune dysregulation, and gut microbiota dysbiosis. Melanin, a natural biopolymer with robust anti-inflammatory and antioxidant properties, presents a promising treatment avenue for UC. Probiotics, particularly Escherichia coli Nissle 1917 (EcN), have gained recognition for their role in restoring gut homeostasis. In this study, we genetically engineered EcN to overexpress tyrosinase (EcN-T), facilitating the biosynthesis of melanin specifically for UC treatment. The engineered probiotics demonstrated superior therapeutic efficacy compared to either melanin or EcN administered alone, highlighting a synergistic effect. EcN-T not only exhibited significant capabilities in scavenging reactive oxygen species and restoring gut microbiota but also possessed the characteristic of enhancing gut colonization time, thereby extending the dosing frequency. Moreover, EcN-T showcased novel mechanisms, such as the restoration of the intestinal mucosal barrier and the elevation of short-chain fatty acid levels. Additionally, EcN-T inhibited M1 macrophage polarization through Hypoxia-Inducible Factor 1-alpha (HIF-1α)dependent glycolytic reprogramming, underscoring its immunomodulatory potential. Collectively, these findings provide new insights into the therapeutic potential of EcN-T for UC treatment, offering a novel strategy that enhances treatment efficacy while potentially reducing side effects associated with conventional therapies.
Human skin-derived neural crest (NC)-like stem cells present a highly accessible, autologous source of multipotent cells, with the potential to differentiate into a variety of cell types, including Schwann cells (SCs). However, these cells quickly lose their stem-like characteristics in vitro and eventually limit their ability to form functional SCs. To overcome this, we investigated SOX10 upregulation, the key regulator of NC formation and multipotency, using both small chemical (Forskolin and RepSox) treatment and genetic modification. Remarkably, SOX10 upregulation highly increased SC gene expression instead of NC markers, though Forskolin-RepSox also triggered melanocytic and smooth muscle gene markers alongside reduced NC genes. In contrast, genetic SOX10 upregulation enhanced both SOX10 and NC gene expression without inducing alternative lineages. Continuous SOX10 expression was necessary for increased SC protein markers, and differentiating SOX10-overexpressing cells on immobilized NRG1 further enhanced SC markers and induced a distinct, elongated morphology typical for myelinating SCs. Therefore, this study introduces a rapid, efficient method to derive SC-like cells from the skin-derived NCs, highlighting their potential in regenerative medicine for cell therapy and disease modeling applications.
Inflammatory bowel disease (IBD) encompasses a group of intestinal disorders, primarily Crohn's disease (CD) and ulcerative colitis (UC), characterized by chronic inflammation of the digestive tract. Despite extensive research, the etiology of IBD remains largely unknown, and its progression and prognosis are unpredictable, often involving uncontrolled disease behavior. Current diagnostic and monitoring techniques, such as endoscopy, scoring systems, computed tomography, and ultrasound, provide valuable tools for assessing and monitoring disease progression; but are often used in conjunction with biomarker testing to achieve rapid and accurate results. Recent advances in biosensors, which integrate biorecognition elements with signal transduction platforms, offer immense potential to improve IBD diagnostics by enabling real-time, precise, and non-invasive detection of biomarkers such as C-reactive protein, calprotectin, and cytokines. This review examines existing IBD diagnostic techniques, their limitations, and the emerging role of biosensors in addressing these challenges. It explores the development of electrochemical and optical biosensors, highlights the key biomarkers utilized in these technologies, and identifies challenges and future opportunities for advancing next-generation biosensors for IBD diagnostics and monitoring. These innovations hold promise for enhancing IBD diagnosis, monitoring, and personalized disease management.
The human eye, a masterpiece of evolution, orchestrates the intricate process of vision. The retina is a tissue with a layered structure that plays a critical role in converting light signals into neural impulses interpretable by the brain. Various eye conditions such as glaucoma, retinitis pigmentosa, age-related macular degeneration, and other retinopathies are characterized by damage or degeneration in the retina. Recent strides in organoid cultivation and advanced three-dimensional (3D) bioengineering technologies offer promising avenues for potential therapeutic interventions. Compared to traditional two-dimensional cell culture models, which are non-natural and limited in accuracy, 3D models, including organoids, electrospinning constructs, microfabrication-based scaffolds, and hydrogel systems, are more delicate, especially in recapitulating tissue architecture, offering spatial patterning, and enabling vascularization. Retinal organoids are 3D multicellular structures derived from stem cells that can mimic the retina's layered architecture and functionality. However, their inherent complexity, including the presence of multiple differentiated cell types, may not be necessary for all disease modeling applications. In contrast, engineered 3D technologies can be tailored to specific retinal diseases by incorporating only the most relevant cell types, matrix stiffness, and spatial arrangements, offering greater experimental control and reproducibility in targeted therapeutic testing. In the following paper, we will discuss organoid generation in detail. Besides retinal organoids, bioprinting is another promising avenue for regenerative medicines. We further review a suite of 3D fabrication strategies, including inkjet and laser-assisted bioprinting, electrospun scaffolds, and hydrogel systems, and evaluate their current and potential applications in modeling retinal diseases and developing translational therapies. We will also delve into the contemporary advancements in retinal therapies, particularly emphasizing the roles and prospects of organoid and engineered 3D technologies.

