The aim of the thesis was to develop antimicrobial wipes to ensure hygiene when washing at low temperatures and to determine the effect of increasing the number of antimicrobial wipes in the wash bath on the reduction of bacterial growth of gramme-negative Escherichia coli (E. coli) and gramme-positive Staphylococcus aureus (S. aureus). A nonwoven fabric made of 100% viscose (CV) was treated with the antimicrobial agent 3-(trimethoxysilyl)-propyldimethylalkylammonium chloride (SiQAS) using an impregnation process. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were used to determine the morphological and chemical properties of the finished CV wipes, and a bromophenol blue (BPB) reagent test was used to determine the suitability of the commercially available detergents Ariel Colour+ and Perwoll to maintain bio-barrier activity during the washing process. The adequacy of household laundry hygiene when washing at 30 °C in the presence of one and three finished CV wipes was determined according to the standard method SIST EN 17658:2021. The application of SiQAS formed a uniform film on the CV fibres, slightly increased the roughness and slightly blurred the characteristic longitudinal lines of the viscose fibres. The results of FT-IR analysis confirmed the presence of an antimicrobially active quaternary ammonium group with a long alkyl chain of SiQAS on the CV fibres. Washing with Perwoll preserved the activity of the bio-barrier better than washing with Ariel Colour+, as it only led to a slightly lower adsorption of the BPB reagent on the treated CV fibres after washing and maintained the intensity of the blue colouration. Nevertheless, the addition of treated CV wipes did not ensure sufficient washing hygiene at low temperatures as it did not reflect the effective reduction of E. coli and S. aureus bacteria. The addition of three treated CV wipes to the wash bath slightly reduced the microbial load during low temperature washing, as it prevented the transfer of E. coli and S. aureus by 0.77 and 1.57 log CFU/mL, respectively, while slightly reducing the number of these bacteria in the effluent by 0.66 (S. aureus) and 0.16 log CFU/mL (E. coli). Further optimisation of the process is required to achieve adequate hygiene in low-temperature washing with SiQAS treated wipes.
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