Towards a multi‐sensor system for the evaluation of aseptic processes employing hydrogen peroxide vapour (H₂O₂)

Abstract

The presented work focuses on the development of a multisensor system for the evaluation of aseptic processes employing hydrogen peroxide vapour. In a first step, selected commercially available gas sensors have been investigated on crosssensitivity towards hydrogen peroxide vapour and humidity. An MOX (TGS 816, Figaro) and a solid-electrolyte gas sensor (SO-A0-250, Electrovac) (l-probe) have shown good characteristics in terms of sensitivity towards HPV, considering also reproducibility, long-term drift and stability. Further, the sterilization effect of HPV has been investigated by means of the microbial reduction test. A correlation between the microbial reduction of Bacillus subtilis spores and the sensor response in hydrogen peroxide atmosphere has been established. Based on this correlation the microbial reduction may be estimated by means of the sensor output over a wide range of parameters.

Multi‐sensor chip for the investigation of different types of metal oxides for the detection of H2O2 in the ppm range

“…These are typically in the range of 3/1 for oxidizing gases such as O 2 up to a ratio of 5/1 for reducing gases such as H 2 or methane, for instance [20]. In earlier works however, similar sensitivities as by the results presented here have been observed upon the exposure of commercially available n-type semiconductor gas sensors with H 2 O 2 in the lower percent range [7].…”

“…For an oxidizing gas, the converse mechanism will operate and the resistance will rise [21]. Though, the same type of behavior was observed in previous studies for the exposure to H 2 O 2 in a higher concentration range using commercially available n-type semiconductor gas sensors with not exactly specified composition of the sensing films [7]. To explain the decrease of the resistance with increasing H 2 O 2 concentration, one has additionally to take into consideration the mechanism of reaction concerning the decomposition of H 2 O 2 .…”

“…Measurements with commercially available sensors of the same type under H 2 O 2 atmosphere have shown that H 2 O shifted the sensor signal of an n-type semiconductor in the same direction such as hydrogen peroxide. However, the response on H 2 O 2 was about ten times higher [7].…”

“…Previous works have shown that calorimetric‐type gas sensors are suitable for monitoring H 2 O 2 concentrations in the range between 1 and 8% v/v . This is equally true for commercially available metal‐oxide‐semiconductor gas sensors . While the lower limit of detection (LOD) in case of the calorimetric gas sensors, which determine the exothermic energy due to a catalytic reaction, is in the range of approximately 5000 ppm, it is assumed that metal‐oxide gas sensors respond at lower concentrations.…”

Copper oxide nanofibres for detection of hydrogen peroxide vapour at high concentrations

“…For the detection of H 2 O 2 vapour currently amperometric, calorimetric and n-type semiconducting gas sensors are discussed in literature [10][11][12]. The application field of semiconducting gas sensors is wide spread.…”