Dilpreet Singh
Pharmaceutical residues persist across wastewater, surface water, sediments, sludge, and reuse systems, creating temporally variable mixtures that are incompletely captured by episodic monitoring and unevenly removed by conventional treatment. This critical review evaluates nanosensors and nanosorbents for pharmaceutical-pollution monitoring and control using matrix recovery, reference-method bias, assay time, breakthrough behavior, regeneration retention, leaching, and life-cycle burden as performance criteria. Nanosensors offer rapid, low-volume detection, but field evidence remains limited by fouling, calibration drift, cross-reactivity, and scarce multiweek validation. Nanosorbents provide high surface area and tunable selectivity, yet equilibrium capacities frequently overstate performance because continuous-flow breakthrough, multisolute competition, and repeated regeneration are underreported. The strongest evidence supports hotspot surveillance, near-line monitoring, hospital or manufacturing sidestream treatment, and modular reuse polishing. Wider deployment requires authentic-matrix testing, standardized reporting, particle containment, action-linked thresholds, and integrated techno-economic and life-cycle assessment. Thus, nano-enabled systems are most credible as targeted modules complementing analytical and treatment infrastructure.