The functionality of textiles can be complemented by using a wide variety of modification technologies. This study focuses on textile modification with sol-gel technology as a part of smart sock prototype development. Zinc acetate dihydrate (ZAD) is integrated into sol synthesis and used as modifier thus improving modified cotton yarn mechanical properties and also can prolong time between washing, taking into account modifiers antimicrobial properties. Four hanks of pure cotton yarns with length of 300 m, were modified with silica-based sol with 7,5 wt% ZAD as a modifier. As a part of this study tensile strength and elongation of yarn was determined and changes in liner density were observed. Average yarn linear density increases by 19 % and linear density for knitted samples increases by 2,6 %. Therefore, yarn strength for 80 % of modified samples shows mean value of 2,32 N, that is 17 % higher than unmodified samples.