Validation of colorimetric assays for hydrogen peroxide, nitrate and nitrite ions in complex plasma‐treated water solutions

Abstract

Liquids treated with cold plasma emerged as ‘redox drugs’ in biomedicine, as sources of reactive oxygen and nitrogen species targeting cellular functions, including wound healing and cancer progression. The use of cell culture media as starting liquid, however, challenges the identification of plasma‐generated chemistry, limited by the presence of many reactive species and organic compounds. Available detection methods need, therefore, to be confirmed in these liquids to avoid inaccurate results. In this research, robustness, linearity, accuracy and specificity of three colorimetric assays are investigated to detect H2O2, NO2− and NO3−, predominant plasma‐induced products. The results clearly highlight the presence of some factors affecting the detection in cell culture media like high concentrations of chlorides found interfering with the detection of NO3− in the medium.

Thermosensitive hydrogels to deliver reactive species generated by cold atmospheric plasma: a case study with methylcellulose

“…The concentration of NO 3 − was not quantified due to potential interactions of the release media with the chemical probe. 29…”

“…The concentration of NO 3 − was not quantified due to potential interactions of the release media with the chemical probe. 29 2.4 Characterization of methylcellulose 2.4.1 Rheological properties. Rheological properties were assessed by means of dynamic oscillatory tests, using a rheometer (Discovery HR-2, TA Instruments) equipped with a 20 mm parallel plate geometry.…”

Anticancer Effects of Plasma-Treated Water Solutions from Clinically Approved Infusion Liquids Supplemented with Organic Molecules

“…It can be noted that H 2 O 2 in PT-SIII is not present (<10 μM, limit of detection, LOD, of the colorimetric assay), 27 after both O 2 -and air-fed DBDs, for treatment times up to 300 s (Figure 2A). On the contrary, when L-tyrosine is added (300 mg/L), the generation of H 2 O 2 occurs, with a trend dependent on the treatment time and on the amount of O 2 in the feed (Figure 2B).…”

“…Disposable plastic cuvettes (Bio-Rad, Hercules, CA) with a semi-micro volume of 1 mL and 10 mm optical length were used. Both assays were specifically validated in the case of PTWS as shown in our previous paper . To study how the PTWS chemical composition changes over time, chemical analyses were carried out immediately after plasma treatment and after up to 15 days of storage at 4 and 25 °C.…”

Plasma‐treated liquids in medicine: Let's get chemical

“…One of the main limitations is the detection and quantification of RONS in matrices like PTLs, challenged by potential inaccuracies and artifacts. [4,13] This aspect becomes more relevant as the chemical complexity of the starting liquid increases. We will briefly discuss these three groups of liquids and the effect of the plasma treatment on each of them.…”