There is an emerging scientific interest in the use of nanoparticle fertilizers for enhanced agricultural and bioenergy crop production to meet the growing food and energy demands of the world. The objective of designing the nanoparticle fertilizers is to effectively deliver the required nutrients for the plants without adding large quantities of fertilizer to the environment. However, most reports on nanoparticle fertilizers so far, involved the addition of nanoparticles to the hydroponic system or the soil. In this study, we report a new modified seed presoak strategy using a drop of Fe-enriching hematite nanoparticle dispersion to enhance plant growth and production in four different legume species, i.e., chickpea, green gram, black bean, and red bean. The hematite nanoparticle fertilizer drop promoted a 230-830% increase in plant growth with green gram showing the highest increase, based on our prolonged and statistically reliable growth studies. In general, we observed an increase in the survival span of plants, a twofold increase in fruit production per plant, nearly two times faster fruit production, and healthy secondgeneration plants with the nanoparticle treatment; however, there were slight species-specific variations. We used a novel multimodal material characterization approach combining three techniques, hyperspectral imaging, Fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma optical emission spectroscopy (ICP-OES), to evaluate the internalization and transport of the nanoparticle fertilizer within the plants. Our results indicated that the hematite nanoparticles were transported through the roots and stems and were localized in the leaves after 10 days of growth in pots of soil. Therefore, the modified seed presoaking method using a drop of hematite nanoparticle will be highly attractive in enhancing plant growth and health, while minimizing environmental impacts.

Application of different engineered nanomaterials is fast‐growing, leading to increased chances of environmental release. Consequently, a robust preliminary detection method for nanomaterials in major ecological environments is beneficial. We report a facile strategy using intensity and number metric of dynamic light scattering to detect presence of nanomaterials in river water. Samples from eight locations of the Tennessee River within Chattanooga were analyzed using our dynamic light scattering technique as a representative assessment of an urban region of Southeastern United States. The average particle sizes (108–294 nm) indicated a possibility of nanomaterials in this region. The results were complemented via scanning electron microscopy. We found that a criteria of identifying peaks at the smallest size distribution for the intensity metric was useful in detecting presence of nanomaterials in environmental samples. The novelty of our approach is the ability to rapidly assess environmental water in solution form with minimum sample preparation artifacts.

Nanoparticles (NPs) are considered as one of the most promising drug delivery vehicles and a next-generation solution for current medical challenges. In this context, variables related to flow of NPs such as the quantity of NPs lost during transport and flow trajectory greatly affect the clinical efficiency of NP drug delivery systems. Currently, there is little knowledge of the physical mechanisms dominating NP flow inside the human body due to the limitations of available experimental tools for mimicking complex physiological environments at the preclinical stage. Here, we report a coupled experimental and computational fluid dynamics (CFD)-based novel in vitro approach to predict the flow velocity and binding of NP drug delivery systems during transport through vasculature. Poly(hydroxyethyl)methacrylate hydrogels were used to form soft cylindrical constructs mimicking vascular sections as flow channels for synthesized iron oxide NPs in these first-of-its-kind transport experiments. Brownian dynamics and material of the flow channels played key roles in NP flow, based on the measurements of NP flow velocity over seven different mass concentrations. A fully developed laminar flow of the NPs under these conditions was simultaneously predicted using CFD. Results from the mass loss of NPs during flow indicated a diffusion-dominated flow at higher particle concentrations but a flow controlled by the surrounding fluid and Brownian dynamics at the lowest NP concentrations. The CFD model predicted a mass loss of 1.341% and 6.253% for the 4.12 g·mL−1 and 2.008 g·mL−1 inlet mass concentrations of the NPs, in close confirmation with the experimental results. This further highlights the reliability of our new in vitro technique in providing mechanistic insights of NP flow for potential preclinical stage applications.