*Antimicrobial Fabrics Impregnated with Ag Particles Included in Silica Matrices DOI: http://dx.doi.org/10.5772/intechopen.91631*

The inoculum was made from 24-h cultures that were in an oven at 37°C. Suspensions with physiological solution were obtained by adjusting the turbidity to 0.5 of the McFarland scale (1.5 × 108 Ufc/ml). A dilution was then made to obtain a bacterial suspension of 1.5 × 106. After the incubation period of the plates inoculated with the selected strains, the zone of inhibition (ZOI) was recorded. The results were obtained from the average of four measurements taken for each triplicate. In addition, the standard deviation between measurements was determined. **Figures 11** and **12** show the photographic records of the trial and those observed through the magnifying glass of the fabrics against *E. coli*. It can be seen that there is an inhibition halo that is identified as a space adjacent to the fabric (transparent culture medium). There are no noticeable differences in the measures of the ZOI of the fabrics that contained the additives in spite of the washing cycles; therefore it can be concluded that the impregnation method has high durability against washing. Taking into account the values of ZOI, 0.6 ± 0.2 for KBI and 0.7 ± 0.2 for K3BI, it can be said that only at 20 wash cycles there is a decrease in the antibacterial effect.

**Figure 10.** *Photographs of bacterial strains used in the assay.*

**Figure 11.** *Antibacterial test of fabrics impregnated with the pad-dry-cure method against* Escherichia coli*.*

*Waste in Textile and Leather Sectors*

at 37°C [14, 46].

environment and be related to pathologies affecting human health. The culture medium used is BVAC: 5 g NaCl, 5 g yeast extract, 10 g casein peptone, and 15 g of bacteriological agar 1 l of distilled water. Then, plates were prepared with 15 ml of the culture medium BVAC and inoculated with the inoculum previously prepared, which spread throughout the plate with sterile swabs. Finally, the fabrics were added treated and untreated. The plates were incubated for 24 h

*SEM micrographs of the control fabric (above) and the fabrics impregnated with the pad-dry-cure method KBI and K3BI (medium and down) and the fabrics impregnated with the pad-dry-cure method, tested against* 

**12**

**Figure 9.**

Aspergillus *sp.*

The photographs of the agar diffusion test against *S. aureus* are shown in **Figures 13** and **14**, in which a halo of inhibition is observed for the fabrics impregnated with the biocide while in the control fabric there is growth throughout the plate.

The photographs obtained through the magnifying glass clearly show the interface of fabric-culture medium-bacterial growth for fabrics with biocide, thus affirming their inhibitory effect. With respect to the washing cycles, they have the same tendency as described for *E. coli*, producing a slight decrease in activity only in the washing cycle number 20.

#### **Figure 12.**

*Images observed with magnifying glass of the control fabric and the fabrics impregnated with the pad-dry-cure method, tested against* Escherichia coli.

**15**

*Antimicrobial Fabrics Impregnated with Ag Particles Included in Silica Matrices*

As a closing of this chapter, it can be concluded that antimicrobial fabrics were obtained from the pad-dry-cure method, using the samples synthesized on silica base with C and Ag. The cotton cloth used was evaluated in antifungal tests with strains *C. globosum* and *Aspergillus* sp., according to the modified standard method DIN 5393, and by antibacterial assays through the agar-based diffusion method (SN

*Images observed with magnifying glass of the control fabric and the fabrics impregnated with the pad-dry-cure* 

On the other hand, the results were good for both the inhibition of fungal and bacterial strains. In addition, there was a high degree of persistence of the additives after the wash cycles before antimicrobial tests, with inhibition being recorded up

Since most of the work focuses on the inhibitory effect of Ag against bacteria, the mechanisms of inhibition or lethality of surfaces with antifungal compounds are poorly understood. In recent years there has been an effort to increase research on antimicrobial fabrics, but the vast majority of these publications focus on bacterial research and only some conduct resistance tests against fungi. If the number of investigations in general is reviewed, a marked increase is observed in the last 5 years. However, the number of investigations on antibacterial fabrics is higher than the number of investigations on antifungal fabrics. However, taking into account the importance of fungal infections in human health, considering that the incidence of fungal infections is increasing and the associated health costs are high, studies should also focus on this field and interest on antifungal fabrics should be growing. The antimicrobial properties of silver have been known for many years, but recently

it has begun to understand the mechanisms by which silver inhibits the growth of microorganisms, although much remains to be investigated. There are several investigations about the biocidal effect and mode of action of silver ions against bacteria, especially against *E. coli*; however, the antifungal effects and the mode of action of nano-Ag against fungi have not yet been studied in depth, and it remains unknown.

*DOI: http://dx.doi.org/10.5772/intechopen.91631*

**5. Conclusions**

**Figure 14.**

to 20 cycles.

195920-1992), against *E. coli* and *S. aureus*.

*method, tested against* Staphylococcus aureus*.*

*Antimicrobial Fabrics Impregnated with Ag Particles Included in Silica Matrices DOI: http://dx.doi.org/10.5772/intechopen.91631*

#### **Figure 14.**

*Waste in Textile and Leather Sectors*

the washing cycle number 20.

plate.

**Figure 12.**

*method, tested against* Escherichia coli.

The photographs of the agar diffusion test against *S. aureus* are shown in **Figures 13** and **14**, in which a halo of inhibition is observed for the fabrics impregnated with the biocide while in the control fabric there is growth throughout the

The photographs obtained through the magnifying glass clearly show the interface of fabric-culture medium-bacterial growth for fabrics with biocide, thus affirming their inhibitory effect. With respect to the washing cycles, they have the same tendency as described for *E. coli*, producing a slight decrease in activity only in

*Images observed with magnifying glass of the control fabric and the fabrics impregnated with the pad-dry-cure* 

*Antibacterial assay of fabrics impregnated with the pad-dry-cure method against* Staphylococcus aureus*.*

**14**

**Figure 13.**

*Images observed with magnifying glass of the control fabric and the fabrics impregnated with the pad-dry-cure method, tested against* Staphylococcus aureus*.*
