Nano Textile Testing

Rujido-Santos, Iria, et al. Spectrochimica Acta Part B: Atomic Spectroscopy 195 (2022): 106505.

The release of silver nanoparticles (AgNPs) from nano textiles was investigated using single particle inductively coupled plasma mass spectrometry (spICP-MS) for nanoparticle concentration and size distribution analysis. The extraction procedure employed orbital-horizontal shaking with ultrapure water (10 mL), ensuring nanoparticle stability during the release process. Filtration (0.22, 0.45, and 5.0 μm) and centrifugation steps were tested to assess their impact on AgNP stability, with 5.0 μm filtration shown to have no significant effect on the nanoparticle concentration and size distribution.

The method demonstrated a limit of detection of 4.59 × 10⁴ AgNPs per gram of textile, with a quantification limit of 1.53 × 10⁵ AgNPs, and a size detection limit of 12 nm. Repeatability of the procedure was high, with coefficients of variation of 14% for concentration and 6% for size. Analytical recovery assays of standard AgNPs yielded recoveries within the 102–113% range.

Despite the low extraction efficiency (0.3–9.0%) due to the strong fixation of AgNPs to the fabric, this methodology proved robust and efficient for characterizing released AgNPs. The findings highlight the effectiveness of spICP-MS for assessing nanoparticle release from nano textiles, providing valuable insights into their environmental and safety implications.

Lorenz, Christiane, et al. Chemosphere 89.7 (2012): 817-824.

This study investigates the release of silver from eight commercially available nano textiles during a washing and rinsing cycle, with a focus on the characterization of silver nanoparticles (AgNPs) and their antimicrobial functionality. The silver released was size-fractionated and analyzed using electron microscopy, revealing the presence of various silver species, including AgCl nanocomposites, AgCl nanoparticles, nanosilver sulfide, and metallic silver.

Among the textiles, three contained nanosized silver, another used metallic silver wire, and four had silver in undeclared forms. The initial silver content ranged from 1.5 to 2925 mg Ag/kg. Only four textiles leached detectable silver, with 34–80% of the silver in particles larger than 450 nm. Microscopic analysis confirmed the presence of agglomerated nanoparticles, with AgCl being the most frequently observed form in washwater.

The antimicrobial properties of the textiles were tested before and after washing. Textiles containing nanosilver exhibited the highest antimicrobial activity, while textiles with metallic silver wire or low silver content showed no reduction in bacterial growth. This study underscores the variability in silver release from nano textiles and highlights the role of silver form in determining antimicrobial efficacy. The results suggest that AgCl nanoparticles are the predominant silver species released during washing, raising concerns about environmental implications.