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Abstract Chronic wounds present significant therapeutic challenges due to prolonged inflammation and bacterial infections, impeding healing. Conventional medicinal dressings typically deliver a single drug with a fixed release profile and lack responsiveness to variations in wound size, nature, or severity. This study introduces an innovative microneedle (MN) patch designed with different microneedle geometries and capable of dual‐drug delivery to address irregular wounds and complex therapeutic requirements. Utilizing CO₂ laser lithography, microneedle molds are fabricated with diverse geometries by precisely controlling laser parameters such as speed, power, and focus, achieving needle heights ranging from 162 ± 30 µm to 1570 ± 40 µm. The patch facilitates simultaneous delivery of simvastatin (SIM) for anti‐inflammatory and tetracycline hydrochloride (TH) for antibacterial properties, targeting different skin depths. In vitro diffusion studies confirm geometry‐dependent drug release profiles, with SIM achieving controlled release over three days and TH exhibiting sustained release over four days. Biocompatibility assays confirmed safety and enhanced fibroblast migration is noted in wound‐healing studies. Antimicrobial testing reveals a 99.9% reduction in bacterial viability. This cost‐effective and scalable approach enables precise, localized delivery and customization of MN arrays to match various wound geometries, offering a versatile platform for personalized medicine and improved chronic wound management. 

Bioelectronic medicine is emerging as a powerful approach for restoring lost endogenous functions and addressing life-altering maladies such as cardiac disorders. Systems that incorporate both modulation of cellular function and recording capabilities can enhance the utility of these approaches and their customization to the needs of each patient. Here we report an integrated optogenetic and bioelectronic platform for stable and long-term stimulation and monitoring of cardiomyocyte function in vitro. Optical inputs are achieved through the expression of a photoactivatable adenylyl cyclase, that when irradiated with blue light causes a dose-dependent and time-limited increase in the secondary messenger cyclic adenosine monophosphate with subsequent rise in autonomous cardiomyocyte beating rate. Bioelectronic readouts are obtained through a multi-electrode array that measures real-time electrophysiological responses at 32 spatially-distinct locations. Irradiation at 27 μW mm−2 results in a 14% elevation of the beating rate within 20–25 min, which remains stable for at least 2 h. The beating rate can be cycled through “on” and “off” light states, and its magnitude is a monotonic function of irradiation intensity. The integrated platform can be extended to stretchable and flexible substrates, and can open new avenues in bioelectronic medicine, including closed-loop systems for cardiac regulation and intervention, for example, in the context of arrythmias. 

The efficient transition of hPSCs to definitive endoderm (DE) progeny is an essential step toward disease modeling and the manufacturing of a wide range of cellular therapeutics in medical relevant quantities. Two-photon excited fluorescence (TPEF) imaging, as a non-invasive, non-destructive, label-free modality for metabolic studies, reveals the distinct metabolic switches during DE differentiation in a real-time monitoring mode. Since metabolic pathways orchestrate important regulatory mechanisms that influence and determine cell fate decisions, TPEF imaging serves as an important enabling technology in hPSC-based tissue engineering applications affording non-invasive determination of metabolic biomarkers and informing optimizations of hPSCs differentiation processes.