ABSTRACT

This project explores the synthesis and application of silver nanoparticles in the development of antibacterial wound dressings. Utilizing a green synthesis approach involving neem leaf extract, silver nanoparticles were produced and incorporated into cotton gauze. The modified dressings demonstrated significant antibacterial activity against both gram-positive and gram-negative bacteria, specifically *E. coli* and *S. aureus*. The findings support the potential for low-cost, eco-friendly materials in medical applications, especially in resource-limited settings.

STATEMENT OF THE PROBLEM

Wound infections are a major health concern, particularly in developing countries where access to modern antibiotics and sterile supplies is limited. There is a need for cost-effective and efficient wound dressings that can prevent infection and promote healing. Traditional dressings often fail to address microbial resistance and secondary infections, necessitating the development of alternatives such as silver nanoparticle-infused materials.

HYPOTHESIS

Incorporating biosynthesized silver nanoparticles into cotton gauze will result in a wound dressing with enhanced antibacterial properties compared to ordinary gauze dressings.

OBJECTIVES

1. To synthesize silver nanoparticles using neem (Azadirachta indica) extract.
2. To develop antibacterial wound dressings by impregnating cotton gauze with the synthesized nanoparticles.
3. To evaluate the antibacterial efficacy of the developed dressings against *E. coli* and *S. aureus* using standard microbiological assays.

BACKGROUND INFORMATION

Silver has been utilized for its antimicrobial properties for centuries. The advent of nanotechnology has enabled the production of silver nanoparticles (AgNPs) which exhibit superior antimicrobial activity due to their high surface area-to-volume ratio. Green synthesis methods using plant extracts provide an eco-friendly, sustainable approach to nanoparticle production. Neem is widely known for its medicinal properties and serves as a reducing and stabilizing agent in AgNP synthesis. This project harnesses these attributes to create antibacterial dressings that could offer better protection in wound management.

MATERIALS

• Fresh neem leaves
• Silver nitrate (AgNO₃)
• Distilled water
• Cotton gauze
• Petri dishes
• Nutrient agar
• Cultures of *E. coli* and *S. aureus*
• Incubator
• Sterile forceps
• Beakers
• Filter paper

METHODOLOGY

1. Preparation of Neem Extract:
Fresh neem leaves were washed, boiled in distilled water, and filtered to obtain an extract.

2. Synthesis of Silver Nanoparticles:
A 1 mM solution of silver nitrate was mixed with neem extract and left at room temperature. A change in color indicated the formation of silver nanoparticles.

3. Fabrication of Antibacterial Dressings:
Sterile cotton gauze was immersed in the nanoparticle solution, dried at room temperature, and stored in sterile conditions.

4. Antibacterial Testing:
Agar well diffusion method was used. The test organisms were inoculated on nutrient agar plates. Gauze samples were placed on the plates and incubated for 24 hours at 37°C. Zones of inhibition were measured.

RESULTS

The silver nanoparticle dressings exhibited clear zones of inhibition against both *E. coli* and *S. aureus*, with larger diameters compared to untreated gauze. This confirms the effectiveness of the biosynthesized nanoparticles in preventing bacterial growth.

DISCUSSION

The green synthesis method proved to be effective and eco-friendly. Neem extract functioned well in reducing silver ions to nanoparticles. The antibacterial activity observed supports prior studies on the effectiveness of silver nanoparticles. The dressings can potentially reduce infections in wounds and lower the reliance on antibiotics, especially where resistant strains are prevalent.

RECOMMENDATIONS

Further testing should be carried out using in vivo models to assess biocompatibility and healing effects. Storage stability and optimal concentration of nanoparticles should also be evaluated for scalability and mass production.

CONCLUSION

Silver nanoparticle-infused wound dressings offer an effective antibacterial barrier. Using plant extracts like neem for synthesis is both cost-effective and sustainable. Such innovations can significantly enhance wound care in underserved areas and contribute to the fight against antibiotic resistance.