Synthesis of a Dual-Functional Nanofertilizer by Embedding ZnO and CuO Nanoparticles on an Alginate-Based Hydrogel

Ultrasonication-Assisted Synthesis of CuO-Decorated Montmorillonite K30 Nanocomposites for Photocatalytic Removal of Emerging Contaminants: A Response Surface Methodology Approach

Environmental pollution is increasing worldwide due to population and industrialization. Among the various forms of pollution, water pollution poses a significant challenge in contemporary times. In this study, we synthesized CuO-decorated montmorillonite K30 (MK30) nanosheets via a simple ultrasonication technique. The structural, morphological, compositional, and optical properties of the synthesized nanocomposites were evaluated using advanced instrumentation techniques. The morphology of CuO was cubic and cubic CuO evenly designed on the MK30, which was proved by Field Emission Scanning Electron Microscopy (FESEM). The adsorption photocatalytic activity of the synthesized cubic CuO/MK30 composites was examined through the degradation of MB under visible light irradiation. The apparent reaction rate constant of 20% CuO/MK30 was 12.5 folds higher than that of CuO. These conditions included a catalyst dosage ranging from 5 to 15 mg, a pH level ranging from to 3-11, and a pollutant concentration ranging from 5 to 20 mg/L. The optimal conditions for MB dye removal were determined using response surface methodology (RSM). A scavenger study of the composite was conducted and verified that •O2- and •OH radicals play an important role in the degradation process. This investigation addressed the process of adsorption and potential removal pathways, with a particular emphasis on the role of functional groups. The environmentally friendly CuO/MK30 nanocomposites exhibited potential as photocatalysts for efficiently absorbing and degrading MB dye and TC drug pollutants. They represent promising candidates for the treatment of industrial wastewater, aiming to mitigate the environmental threats posed by organic pollutants.

Nano hybrid fertilizers: A review on the state of the art in sustainable agriculture

The advent of Nanohybrid (NH) fertilizers represents a groundbreaking advancement in the pursuit of precision and sustainable agriculture. This review abstract encapsulates the transformative potential of these innovative formulations in addressing key challenges faced by modern farming practices. By incorporating nanotechnology into traditional fertilizer matrices, nanohybrid formulations enable precise control over nutrient release, facilitating optimal nutrient uptake by crops. This enhanced precision not only fosters improved crop yields but also mitigates issues of over-fertilization, aligning with the principles of sustainable agriculture. Furthermore, nanohybrid fertilizers exhibit the promise of minimizing environmental impact. Their controlled release mechanisms significantly reduce nutrient runoff, thereby curbing water pollution and safeguarding ecosystems. This dual benefit of precision nutrient delivery and environmental sustainability positions nanohybrid fertilizers as a crucial tool in the arsenal of precision agriculture practices. The intricate processes of uptake, translocation, and biodistribution of nutrients within plants are examined in the context of nanohybrid fertilizers. The nanoscale features of these formulations play a pivotal role in governing the efficiency of nutrient absorption, internal transport, and distribution within plant tissues. Factors affecting the performance of nanohybrid fertilizers are scrutinized, encompassing aspects such as soil type, crop variety, and environmental conditions. Understanding these variables is crucial for tailoring nanohybrid formulations to specific agricultural contexts, and optimizing their impact on crop productivity and resource efficiency. Environmental considerations are integral to the review, assessing the broader implications of nanohybrid fertilizer application. This review offers a holistic overview of nanohybrid fertilizers in precision and sustainable agriculture. Exploring delivery mechanisms, synthesis methods, uptake dynamics, biodistribution patterns, influencing factors, and environmental implications, it provides a comprehensive understanding of the multifaceted role and implications of nanohybrid fertilizers in advancing modern agricultural practices.

Advancement of metal oxide nanomaterials on agri-food fronts

The application of metal oxide nanomaterials (MOx NMs) in the agrifood industry offers innovative solutions that can facilitate a paradigm shift in a sector that is currently facing challenges in meeting the growing requirements for food production, while safeguarding the environment from the impacts of current agriculture practices. This review comprehensively illustrates recent advancements and applications of MOx for sustainable practices in the food and agricultural industries and environmental preservation. Relevant published data point out that MOx NMs can be tailored for specific properties, enabling advanced design concepts with improved features for various applications in the agrifood industry. Applications include nano-agrochemical formulation, control of food quality through nanosensors, and smart food packaging. Furthermore, recent research suggests MOx's vital role in addressing environmental challenges by removing toxic elements from contaminated soil and water. This mitigates the environmental effects of widespread agrichemical use and creates a more favorable environment for plant growth. The review also discusses potential barriers, particularly regarding MOx toxicity and risk evaluation. Fundamental concerns about possible adverse effects on human health and the environment must be addressed to establish an appropriate regulatory framework for nano metal oxide-based food and agricultural products.

Current and emerging nanotechnology for sustainable development of agriculture: Implementation design strategy and application

Recently, agriculture systems have faced numerous challenges involving sustainable nutrient use efficiency and feeding, environmental pollution especially heavy metals (HMs), infection of harmful microorganisms, and maintenance of crop production quality during postharvesting and packaging. Nanotechnology and nanomaterials have emerged as powerful tools in agriculture applications that provide alternatives or support traditional methods. This review aims to address and highlight the current overarching issue and various implementation strategies of nanotechnology for sustainable agriculture development. In particular, the current progress of different nano-fertilizers (NFs) systems was analyzed to show their advances in enhancing the uptake and translocations in plants and improving nutrient bioavailability in soil. Also, the design strategy and application of nanotechnology for rapid detection of HMs and pathogenic diseases in plant crops were emphasized. The engineered nanomaterials have great potential for biosensors with high sensitivity and selectivity, high signal throughput, and reproducibility through various detection approaches such as Raman, colorimetric, biological, chemical, and electrical sensors. We obtain that the development of microfluidic and lab-on-a-chip (LoC) technologies offers the opportunity to create on-site portable and smart biodevices and chips for real-time monitoring of plant diseases. The last part of this work is a brief introduction to trends in nanotechnology for harvesting and packaging to provide insights into the overall applications of nanotechnology for crop production quality. This review provides the current advent of nanotechnology in agriculture, which is essential for further studies examining novel applications for sustainable agriculture.

Sustainable Soil Additives for Water and Micronutrient Supply: Swelling and Chelating Properties of Polyaspartic Acid Hydrogels Utilizing Newly Developed Crosslinkers

Drought and water shortage are serious problems in many arid and semi-arid regions. This problem is getting worse and even continues in temperate climatic regions due to climate change. To address this problem, the use of biodegradable hydrogels is increasingly important for the application as water-retaining additives in soil. Furthermore, efficient (micro-)nutrient supply can be provided by the use of tailored hydrogels. Biodegradable polyaspartic acid (PASP) hydrogels with different available (1,6-hexamethylene diamine (HMD) and L-lysine (LYS)) and newly developed crosslinkers based on diesters of glycine (GLY) and (di-)ethylene glycol (DEG and EG, respectively) were synthesized and characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and regarding their swelling properties (kinetic, absorbency under load (AUL)) as well as biodegradability of PASP hydrogel. Copper (II) and zinc (II), respectively, were loaded as micronutrients in two different approaches: in situ with crosslinking and subsequent loading of prepared hydrogels. The results showed successful syntheses of di-glycine-ester-based crosslinkers. Hydrogels with good water-absorbing properties were formed. Moreover, the developed crosslinking agents in combination with the specific reaction conditions resulted in higher water absorbency with increased crosslinker content used in synthesis (10% vs. 20%). The prepared hydrogels are candidates for water-storing soil additives due to the biodegradability of PASP, which is shown in an exemple. The incorporation of Cu(II) and Zn(II) ions can provide these micronutrients for plant growth.

Development of amine-functionalized fluorescent silica nanoparticles from coal fly ash as a sustainable source for nanofertilizer

Scaling up the synthesis of fluorescent silica nanoparticles to meet the current demand in diverse applications involves technological limitations. The present study relates to the hydrothermal synthesis of water-soluble, crystalline, blue-emitting amine-functionalized silica nanoparticles from coal fly ash sustainably and economically. This study used tertiary amine (trimethylamine) to prepare amine-functionalized fluorescent silica nanoparticles, enhancing fluorescence quantum yield and nitrogen content for nanofertilizer application. The TEM and FESEM studies show that the silica nanoparticles have a spherical morphology with an average diameter of 4.0 nm. The x-ray photoelectron and Fourier transform infrared spectroscopy studies reveal the presence of the amine group at the surface of silica nanoparticles. The silica nanoparticles exhibit blue fluorescence with an emission maximum of 454 nm at 370 nm excitation and show excitation-dependent emission properties in the aqueous medium. With the perfect spectral overlap between silica nanoparticle emission (donor) and chlorophyll absorption (acceptor), fluorescent silica nanoparticles enhance plant photosynthesis rate by resonance energy transfer. This process accelerates the photosynthesis rate to improve the individual plant's quality and growth. These findings suggested that the fly ash-derived functionalized silica nanoparticles could be employed as nanofertilizers and novel delivery agents.

Synthesis and characterization of chitosan-zinc-salicylic acid nanoparticles: A plant biostimulant

The vastly expanding global population raised the demand for profuse food grain production. For food security in India, high yield and nutritional quality of grain crops, both are essential. Zinc is a crucial micronutrient generally deficient in food grains grown in India, reflecting their deteriorating nutritional quality. To address these issues, in the present study, a novel tri-component nanoparticle of chitosan‑zinc-salicylic acid (CS-Zn-SA NPs) has been synthesized by ionotropic gelation method. The average size of synthesized CS-Zn-SA NPs was recorded 13.5 nm by dynamic light scattering (DLS) spectroscopy. The presence of chitosan, zinc and salicylic acid and crosslinking among these components in synthesized nanoparticles has been demonstrated by Fourier transforms infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). Further, synthesized CS-Zn-SA NPs at various concentrations (50-200 ppm) were evaluated for seed germination via seed priming, yield, grain zinc content and defence enzyme activity through the foliar application. CS-Zn-SA NPs revealed significant seed germination activities, 19.8 % higher grain yield, 45.5 % increased grain zinc content and manyfold defence enzyme activities than the control. The obtained results exposed the potential of CS-Zn-SA NPs as a stimulant for effective seedling development, higher yield, a virtuous micronutrient fortifying agent and defence enzyme promoter.

Engineering of PVA/PVP Hydrogels for Agricultural Applications

Hydrogels have gained significant popularity in agricultural applications in terms of minimizing waste and mitigating the negative environmental impact of agrochemicals. This review specifically examines the utilization of environmentally friendly, shapable hydrogels composed of polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) in various casings for crop protection against different pests, fertilizing, and watering. To activate their effectiveness, PVA/PVP hydrogels were loaded with both hydrophilic and hydrophobic environmentally friendly pesticides, namely hydrogen peroxide (HP), the essential oil thymol, and urea as a fertilizer, either separately or in combination. This review covers various physical and chemical approaches used for loading, shaping, and controlling the release profiles of pesticides and fertilizers. Additionally, it explores the evaluation of the chemical composition, structure, classification, rheology, and morphology of the hydrogels as well as their impact on the thermal stability of the encapsulated pesticides and fertilizer, followed by biological tests. These hydrogels significantly contribute to the stabilization and controlled release of essential nutrients and biocides for plants, while maintaining excellent biocidal and fertilizing properties as well as sustainability characteristics. By shedding light on the latest insights into the concepts, applications, and results of these hydrogels, this review demonstrates their immense potential for widespread future use in agriculture.

Zn nutrients-loaded chitosan nanocomposites and their efficacy as nanopriming agents for maize (Zea mays) seeds

Recent breakthroughs in agro-inputs research have led to the development of nanomaterials that can promote precision agriculture and better environmental security. The agricultural sector is increasingly facing the negative impacts of changing climates due to various stress conditions. To curb this scenario, economical and low-risk practices such as decreasing fertilizer inputs and seed priming have been promoted. In the current study, the H. odoratissimum aqueous extract was used to nucleate the Zn ionic species and grow the zinc oxide nanoparticles (ZnO NPs). The developed nanocomposites and their ionic zinc precursor were then integrated into tripolyphosphate (TPP)-crosslinked chitosan (CS/TPP) nanostructures by ionic gelation. Advanced physicochemical characterization techniques (SEM, EDS, TEM, DLS, FTIR, TGA, and XPS) were exploited to report the morphology, hydrodynamic size, surface charge, and structural organization of the developed nanomaterials. These revealed positively charged particles with hydrodynamic size in the 149-257 nm range. The NPs were used as priming agents for Zea mays seeds. At 0.04%, the ZnO-loaded CS/TPP NPs achieved higher root and shoot elongation in 10-day old seedlings compared to other treatments. The pristine CS/TPP NPs, Zn(II)-laden CS/TPP NPs, and ZnO-loaded CS/TPP NPs at 0.01% significantly promoted the early seedling development of seeds under salt stress. This represents the first report showing ZnO integrated chitosan nanocomposites as an auspicious nanopriming agent for stimulating the seed germination of maize. The study envisages offering perspectives on utilizing green nanotechnology to improve the early seedling development of maize. Furthermore, it has the potential to contribute towards UN SDG 2, thus addressing the threats to global food insecurity and doubling agricultural productivity by 2030.

Advanced applications of sustainable and biological nano-polymers in agricultural production

Though still in its infancy, the use of nanotechnology has shown promise for improving and enhancing agriculture: nanoparticles (NP) offer the potential solution to depleted and dry soils, a method for the controlled release of agrochemicals, and offer an easier means of gene editing in plants. Due to the continued growth of the global population, it is undeniable that our agricultural systems and practices will need to become more efficient in the very near future. However, this new technology comes with significant worry regarding environmental contamination. NP applied to soils could wash into aquifers and contaminate drinking water, or NP applied to food crops may carry into the end product and contaminate our food supply. These are valid concerns that are not likely to be fully answered in the immediate future due to the complexity of soil-NP interactions and other confounding variables. Therefore, it is obviously preferred that NP used outdoors at this early stage be biodegradable, non-toxic, cost-effective, and sustainably manufactured. Fortunately, there are many different biologically derived, cost-efficient, and biocompatible polymers that are suitable for agricultural applications. In this mini-review, we discuss some promising organic nanomaterials and their potential use for the optimization and enhancement of agricultural practices.

Engineered Nanomaterials for Improving the Nutritional Quality of Agricultural Products: A Review

To ensure food safety, the current agricultural development has put forward requirements for improving nutritional quality and reducing the harmful accumulation of agricultural chemicals. Nano-enabled sustainable agriculture and food security have been increasingly explored as a new research frontier. Nano-fertilizers show the potential to be more efficient than traditional fertilizers, reducing the amount used while ensuring plant uptake, supplying the inorganic nutrients needed by plants, and improving the process by which plants produce organic nutrients. Other agricultural uses of nanotechnology affect crop productivity and nutrient quality in addition to nano-fertilizers. This article will review the research progress of using nanomaterials to improve nutritional quality in recent years and point out the focus of future research.

Macroalgal-Derived Alginate Soil Amendments for Water Retention, Nutrient Release Rate Reduction, and Soil pH Control

There is a need to develop sustainably sourced products that can address the needs for improved water retention in soils, slow the release rate of fertilizers (to prevent leaching and downstream eutrophication), and control soil pH for use in agriculture. This article investigates the use of industrial kelp solid waste extracted alginate (IW) slurries to produce soil amendment beads, potentially improving soil water retention, acting as slow-release fertilizers (SRFs), and combined with limestone controls soil pH levels. Alginate extracted from the IW was determined to have a lower guluronic (G) to mannuronic (M) acid ratio than pure laboratory-grade (LG) alginate (0.36 vs. 0.53). Hydrogels produced from the IW alginate achieved significantly higher equilibrium swelling ratios (1 wt% IW = 1.80) than LG hydrogels with similar concentrations (1 wt% LG = 0.61). Hydrogel beads were impregnated with ammonium nitrate and potassium chloride to produce potential SRFs. The release rates of K⁺ and NO₃⁻ nutrients from the produced SRFs into deionised water were decreased by one order of magnitude compared to pure salts. The nutrient release rates of the IW-based SRFs were shown to be similar to SRFs produced from LG alginate. Hydrogel beads were impregnated with limestone, and it was determined that the alginate-based hydrogels could significantly decrease the nutrient release rate. Using industrial kelp solid waste extracted alginate slurries shows potential for soil amendments production. This report emphasises, for the first time, the use of a crude alginate product in soil amendment formation. Further, it demonstrates slower release rates and soil pH control.

Nanotechnology-enabled biofortification strategies for micronutrients enrichment of food crops: Current understanding and future scope

Nutrient deficiency in food crops severely compromises human health, particularly in under privileged communities. Globally, billions of people, particularly in developing nations, have limited access to nutritional supplements and fortified foods, subsequently suffering from micronutrient deficiency leading to a range of health issues. The green revolution enhanced crop production and provided food to billions of people but often falls short with respect to the nutritional quality of that food. Plants may assimilate nutrients from synthetic chemical fertilizers, but this approach generally has low nutrient delivery and use efficiency. Further, the overexposure of chemical fertilizers may increase the risk of neoplastic diseases, render food crops unfit for consumption and cause environmental degradation. Therefore, to address these challenges, more research is needed for sustainable crop yield and quality enhancement with minimum use of chemical fertilizers. Complex nutritional disorders and 'hidden hunger' can be addressed through biofortification of food crops. Nanotechnology may help to improve food quality via biofortification as plants may readily acquire nanoparticle-based nutrients. Nanofertilizers are target specific, possess controlled release, and can be retained for relatively long time periods, thus prevent leaching or run-off from soil. This review evaluates the recent literature on the development and use of nanofertilizers, their effects on the environment, and benefits to food quality. Further, the review highlights the potential of nanomaterials on plant genetics in biofortification, as well as issues of affordability, sustainability, and toxicity.

Alginate-based hydrogels embedded with ZnO nanoparticles as highly responsive colorimetric oxygen indicators

Simple fabrication of hydrogel-based colorimetric oxygen indicators as alternative smart materials for oxygen sensitive products and systems.