Studying mass and mechanical property changes during the degradation of a bioadhesive with mass tracking, rheology and magnetoelastic (ME) sensors

In this research, the degradable polymer 4-arm poly (ethylene glycol)-glutaric acid-dopamine (PEG-GA-DM4) was synthesized. The degradation behavior of crosslinked PEG-GA-DM4 bioadhesive was studied with mass tracking, oscillatory rheology, and magnetoelastic (ME) sensors. Changes in mechanical properties were correlated with both dry mass and wet mass changes during the degradation. The results indicate that the loss of mechanical property in the bioadhesive can take place without losing the dry mass. The mass loss profile cannot describe the degradation behavior completely. In addition to studying the degradation of PEG-GA-DM4, this research also confirms the application of ME sensors as a means to study the mechanical and degradation behavior of bioadhesive

Monitoring the long-term degradation behavior of biomimetic bioadhesive using wireless magnetoelastic sensor

The degradation behavior of a tissue adhesive is critical to its ability to repair a wound while minimizing prolonged inflammatory response. Traditional degradation tests can be ex-pensive to perform, as they require large numbers of samples. The potential for using magnetoelastic resonant sensors to track bioadhesive degradation behavior was investigated. Specifically, biomimetic poly (ethylene glycol)- (PEG-) based adhesive was coated onto magnetoelastic (ME) sensor strips. Adhesive-coated samples were submerged in solutions buffered at multiple pH levels (5.7, 7.4 and 10.0) at body temperature (37°C) and the degradation behavior of the adhesive was tracked wirelessly by monitoring the changes in the resonant amplitude of the sensors for over 80 days. Adhesive incubated at pH 7.4 degraded over 75 days, which matched previously published data for bulk degradation behavior of the adhesive while utilizing significantly less material (∼103 times lower). Adhesive incubated at pH 10.0 degraded within 25 days while samples incubated at pH 5.7 did not completely degrade even after 80 days of incubation. As expected, the rate of degradation increased with increasing pH as the rate of ester bond hydrolysis is higher under basic conditions. As a result of requiring a significantly lower amount of samples compared to traditional methods, the ME sensing technology is highly attractive for fully characterizing the degradation behavior of tissue adhesives in a wide range of physiological conditions