Biology subjects

McShane, M. J.

Publications and source records attributed to McShane, M. J..

3 recordsLinked to original sources

bioRxiv2025

NIR Phosphorescent Oxygen Sensors in Natural Hydrogel Matrices

Understanding the effects of sterilization and other treatments over different hydrogels used as matrices for oxygen-sensitive microparticles is essential in designing biocompatible phosphorescent metabolite sensors. In this study, we dispersed oxygen-sensitive microparticles in hydrogel matrices from various natural sources, such as gelatin, alginate, collagen, and Albumin. Subsequently, we comprehensively analyzed their mechanical and rheological properties and oxygen sensitivity before and after treatments, including autoclave and E-beam sterilization and exposure to serum and cell culture conditions. Our findings, encompassing oxygen sensitivity, compression testing, and rheological profiling, consistently indicate that the E-beam sterilization method yields the most reliable results when applied to alginate and Albumin (BSA) matrices containing oxygen-sensing microparticles. Furthermore, BSA gels exhibited robust stability and performance characteristics, demonstrating minimal structural alterations following post-treatment conditions.

bioengineering↗

bioRxiv2025

IN4MER Bioink: A Phosphorescent Biosensing Bio-ink for Multiple Analytes (Glucose, Lactate, Oxygen) Measurements and Temperature Sensing Applications

3D bioprinting has revolutionized tissue engineering by enabling researchers to create much more complex structures than was practical with earlier techniques. Bioprinting uses computer-controlled layer-by-layer deposition of a mixture of hydrogels and living cells and the resulting structures can mimic the complex geometries of many living tissues by incorporating multiple bioinks with varied material properties and cell populations, allowing researchers to design structures that vary not only in shape, but also in mechanical, chemical, and biological properties throughout the bioprinted construct. However, techniques for evaluating these living constructs and monitoring them over time have not yet caught up to these innovations. Here we describe a novel approach to reporting nutrient values in real-time throughout the scaffold itself, accomplished by dispersing oxygen, glucose, and lactate sensitive microspheres within bioinks. These can be noninvasively interrogated using low-cost phosphorescence lifetime readers to determine and track nutrient concentrations across our bioprinted constructs in real time. The wealth of information this technique produces suggests this may provide a powerful new tool for evaluating and designing future bioprinted constructs.

bioengineering↗

bioRxiv2024

Continuous Monitoring of Glucose and Oxygen using an Insertable Biomaterial-based Multianalyte Barcode Sensor

Chronic diseases including diabetes, cardiovascular diseases, and microvascular complications contribute significantly to global morbidity and mortality. Multiplexing technologies offer a promising approach for the simultaneous detection and management of comorbidities, providing comprehensive disease insights. In this work, we describe a miniaturized optical "barcode" sensor with high biocompatibility for continuous monitoring of glucose and oxygen. This enzymatic sensor relies on oxygen consumption in proportion to local glucose levels and the phosphorescence reporting of tissue oxygen with a lifetime-based probe. The sensor was designed to operate in a tissue environment with low levels of dissolved oxygen. The barcode sensor consists of a poly(ethylene) glycol diacrylate (PEGDA) hydrogel with four discrete compartments separately filled with glucose or oxygen-sensing phosphorescent microparticles. We evaluated the response of the barcode hydrogels to fluctuating glucose levels over the physiological range under low oxygen conditions, demonstrating controlled tuning of dynamic range and sensitivity. Moreover, the barcode sensor exhibited remarkable storage stability over 12 weeks, along with full reversibility and excellent reproducibility ([~]6% variability in phosphorescence lifetime). Electron beam sterilization had a negligible impact on the glucose response of the barcode sensors. Furthermore, our investigation revealed minimal phosphorescence lifetime changes in oxygen compartments while exhibiting increased lifetime in glucose-responsive compartments when subjected to alternating glucose concentrations (0 and 200 mg/dL), showcasing the sensors multianalyte sensing capabilities without crosstalk between compartments. Additionally, evaluation of tissue response to sensors inserted in pigs revealed appropriate biocompatibility of the barcodes.

bioengineering↗