An evidence-based environmental perspective of manufactured silver nanoparticle in syntheses and applications: A systematic review and critical appraisal of peer-reviewed scientific papers

• Published in: The Science of the total environment 2010-02, Vol.408 (5), p.999-1006
• Main Authors: Tolaymat, Thabet M., El Badawy, Amro M., Genaidy, Ash, Scheckel, Kirk G., Luxton, Todd P., Suidan, Makram
• Format: Article
• Language: English
• Subjects: Applied sciences; Bimetals; Environmental Pollution; Evidence–based approach; Exact sciences and technology; Format; Global environmental pollution; Metal Nanoparticles - chemistry; Nanocomposites; Nanomaterials; Nanoparticle; Nanoparticles; Nanostructure; Nanotechnology - methods; Particle Size; Pollution; Risk Assessment; Silver; Silver - chemistry; Syntheses; Synthesis
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2009.11.003

Most recently, renewed interest has arisen in manufactured silver nanomaterials because of their unusually enhanced physicochemical properties and biological activities compared to the bulk parent materials. A wide range of applications has emerged in consumer products ranging from disinfecting medical devices and home appliances to water treatment. Because the hypothesized mechanisms that govern the fate and transport of bulk materials may not directly apply to materials at the nanoscale, there are great concerns in the regulatory and research communities about potential environmental impacts associated with the use of silver nanoparticles. In particular, the unlimited combinations of properties emerging from the syntheses and applications of silver nanoparticles are presenting an urgent need to document the predominant salt precursors, reducing agents and stabilizing agents utilized in the synthesis processes of silver nanoparticles to guide the massive efforts required for environmental risk assessment and management. The primary objective of this study is to present an evidence-based environmental perspective of silver nanoparticle properties in syntheses and applications. The following specific aims are designed to achieve the study objective: Aim 1 — to document the salt precursors and agents utilized in synthesizing silver nanoparticles; Aim 2 — to determine the characteristics of silver nanoparticles currently in use in the scientific literature when integrated in polymer matrices to form nanocomposites and combined with other metal nanoparticles to form bimetallic nanoparticles; Aim 3 — to provide a summary of the morphology of silver nanoparticles; and (4) Aim 4 — to provide an environmental perspective of the evidence presented in Aims 1 to 3. A comprehensive electronic search of scientific databases was conducted in support of the study objectives. Specific inclusion criteria were applied to gather the most pertinent research articles. Data and information extraction relied on the type of synthesis methods, that is, synthesized silver nanoparticles in general and specific applications, nanocomposites, and bimetallic techniques. The following items were gathered for: type of silver salt, solvent, reducing agent, stabilizing agent, size, and type of application/nanocomposite/bimetallic, and template (for nanocomposites). The description of evidence was presented in tabular format. The critical appraisal was analyzed in graphical format and discus