Comparison of the physicochemical properties and inactivation against tumor cells of PAW induced by underwater single-hole and multi-hole bubble plasma

Abstract

Plasma-activated water (PAW) regarded as a green alternative is of great interest in biomedicine due to the presence of a rich diversity of aqueous reactive oxygen and nitrogen species (RONS). Optimizing the reactor parameter is an important approach to regulate RONS in PAW to obtain better biological effects. This work mainly focuses on the number of micro holes of the plasma device to realize underwater bubble discharge. By comparing single-hole and multi-hole plasma under the same pulse voltage, the multi-hole plasma would produce a better discharge characteristic, and the prepared PAW presents superior physicochemical properties to realize high level RONS production by means of microbubbles to increase the contact area with water molecules. Furthermore, the A549 lung carcinoma cells are used to verify the inactivation effect induced by PAW treated by underwater single-hole and multi-hole bubble plasma, respectively, and the results show that the multi-hole plasma would induce cell apoptosis reaching up to 57.4%, while only 31.2 % apoptosis efficiency for single-hole plasma. This mainly contributes to the high concentration of key species (NO2−, H2O2, ONOO−/O·2-, and ·OH) produced by multi-hole plasma. This study is helpful to insight into the influence of underwater bubble on chemistry activity of PAW, and promoting the wide applications in biomedical field.

Insights into the mechanisms of plasma physicochemical characteristics on ultralong-lasting plasma-activated water: the influence of DC power polarity on RONS generation

“…Plasma-activated water (PAW) has garnered significant attention for its wide-ranging applications in microorganism inactivation, 1–3 cancer cell eradication, 4,5 dentistry, 6 and wastewater remediation. 7,8 Studies have shown that the effectiveness of PAW is influenced by various factors including pH value and the presence of long-lived reactive oxygen and nitrogen species (RONS) such as NO 2 − and H 2 O 2 in conjunction with short-lived RONS like ˙OH, O 2 ˙ − and 1 O 2 .…”

Generation of neutral pH high‐strength plasma‐activated water from a pin to water discharge and its bactericidal activity on multidrug‐resistant pathogens

“…3 − [4,11,[16][17][18] Typically, a high concentration of long-lived RONS species is believed to give higher bactericidal activity and also can potentially target multidrug resistant (MDR) pathogens. Hence it is desirable to generate PAW having a high concentration of NO 2 − and H 2 O 2 [7,11,14,19,20] and is the subject matter of this study.…”

“…These configurations (a) have their discharge in the gas phase above the water column and (b) can generate high concentrations of RONS in PAW. [6,[15][16][17][18][19] Table 1 summarizes the reported works on PAW generation using P2W and plasma-jet. The type of water used, volume activated, activation time (t a ), pH of the water, the concentration of RONS species, and their corresponding contribution to bactericidal activity are tabulated in Table 1.…”