Engineered PEG–PCL nanoparticles enable sensitive and selective detection of sodium dodecyl sulfate: a qualitative and quantitative analysis

Sodium dodecyl sulfate (SDS) is a widely used anionic surfactant in laboratory, household, and industrial applications, which ultimately enters the environment through various pathways. This has led to significant concerns regarding developing rapid onsite qualitative and quantitative methods for estimating SDS in aqueous solutions. Although a range of high-throughput techniques is currently utilized for SDS quantification, these methods are often expensive, labor-intensive, and require specialized technical expertise. This study developed a novel colorimetric method for the selective and sensitive detection of SDS, utilizing polyethylene glycol-polycaprolactone nanoparticles (PEG-PCL NPs) synthesized via a ring-opening polymerization approach. The synthesized nanoparticles exhibited a distinct colorimetric response to SDS when combined with the Bradford reagent, which acted as a linker molecule. Interference studies demonstrated the high selectivity of the method, even in the presence of various heavy metals and other surfactants. The method showed excellent linearity over a concentration range of 0-200 μg/mL, with a correlation coefficient (<i>R</i> ²) of 0.98. The limits of detection and quantification for the proposed method were determined to be 26.14 μg/mL and 79.23 μg/mL, respectively. These findings indicate that the newly developed method offers high selectivity and sensitivity for SDS detection, making it a promising analytical tool for rapid and onsite estimation.