Michaella Watson, Christopher O’Rourke, Andrew Mills
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引用次数: 0
Abstract
A simple, inexpensive bromophenol blue (BPB), colourimetric ammonia (NH3) sensor is used to monitor the growth of different wound associated bacteria in three different, simple wound models which utilise a typical, readily available, commercial occlusive wound dressing. The 25% colour change point of the sensor is ca. 0.0032%NH3 and its 90% response and recovery times are, 8 and 230 s, respectively. Using P. stuartii as the test species, in a model wound with an occlusive dressing, the increase in the sensor’s colour up to the 25% point correlates with that of the exponential growth of the bacterial species (units: CFU/mL) and a simple mathematical model is used to show that a linear relationship should exist between log(CFU/mL) of the initial inoculum and the time it takes for the sensor to reach its 25% colour change point, the threshold time, TT. This prediction is confirmed using the NH3 producing bacteria, E. coli, E. cloacae, P. stuartii, and K. aerogenes using three different wound models, namely ones in which the ‘wound’ was a non-urea containing agar plug, a urea-containing agar plug and a damaged porcine skin model, respectively. These results suggest that the NH3 sensor has promise as a non-invasive wound monitoring indicator and the additional work required to progress the sensor in this role is discussed briefly.
期刊介绍:
Sensors & Actuators, B: Chemical is an international journal focused on the research and development of chemical transducers. It covers chemical sensors and biosensors, chemical actuators, and analytical microsystems. The journal is interdisciplinary, aiming to publish original works showcasing substantial advancements beyond the current state of the art in these fields, with practical applicability to solving meaningful analytical problems. Review articles are accepted by invitation from an Editor of the journal.