The increasing threat from antibiotic-resistant bacteria has necessitated the development of novel methods to counter bacterial infections. In this context, the application of metallic nanoparticles (NPs), especially gold (Au) and silver (Ag), has emerged as a promising strategy due to their remarkable antibacterial properties. This review examines research published between 2006 and 2023, focusing on leading journals in nanotechnology, materials science, and biomedical research. The primary applications explored are the efficacy of Ag and Au NPs as antibacterial agents, their synthesis methods, morphological properties, and mechanisms of action. An extensive review of the literature on NPs synthesis, morphology, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and effectiveness against various Gram(+/−) bacteria confirms the antibacterial efficacy of Au and Ag NPs. The synthesis methods and characteristics of NPs, such as size, shape, and surface charge, are crucial in determining their antibacterial activity, as these factors influence their interactions with bacterial cells. Furthermore, this review underscores the urgent necessity of standardizing synthesis techniques, MICs, and reporting protocols to enhance the comparability and reproducibility of future studies. Standardization is essential for ensuring the reliability of research findings and accelerating the clinical application of NP-based antimicrobial approaches. This review aims to propel NP-based antimicrobial strategies by elucidating the properties that enhance the antibacterial activity of Ag and Au NPs. By highlighting their inhibitory effects against various bacterial strains and relatively low cytotoxicity, this work positions Ag and Au NPs as promising materials for developing antibacterial agents, making a significant contribution to global efforts to combat antibiotic-resistant pathogens.

Microplastics are ubiquitous in the environment and represent a serious risk to ecosystems and human health. This study describes a prototype sensor designed to detect microplastics by analyzing samples with multiple wavelengths of light. The system uses samples of commercially available microplastics and includes passive low-pass filters to reduce noise for accurate readings. The prototype measures light attenuation and produces color spectra that helps identify microplastics. Its design focuses on precision, electronic control, and optical sensing, making it an affordable option for environmental monitoring. Early experiments demonstrate that the prototype is sensitive and reliable under a variety of conditions. Future improvements may add machine learning and fuzzy logic to increase accuracy and expand its use.

Microplastics are ubiquitous in our environment and significantly threaten ecosystems and human health. This paper presents the design and fabrication of an innovative prototype sensor capable of detecting microplastics by employing multiple wavelengths. Our system combines mechanical, electronic, and optical components, providing an efficient and cost-effective solution for environmental monitoring.