Articular cartilage injury and degenerative disorders are major contributors to joint dysfunction. Because cartilage is avascular and aneural, its intrinsic healing capacity is extremely limited, which continues to present a major clinical challenge. Cartilage organoids, defined as three-dimensional constructs that recapitulate key structural, cellular, and functional features of native cartilage tissue, including cell-cell and cell-matrix interactions, zonal organization, and responsiveness to biochemical and mechanical cues, have emerged as promising platforms for cartilage regeneration and disease research. In this context, three-dimensional (3D) bioprinting offers a powerful top-down strategy for fabricating such organoids with high spatial precision, complementing conventional bottom-up self-assembly approaches. This capability has opened new opportunities for the generation of cartilage constructs with complex architectures and biomimetic functions, highlighting their potential in personalized therapy, disease modeling, and regenerative medicine. This review provides a comprehensive overview of recent progress in 3D bioprinting for cartilage organoid engineering. First, it summarizes advances in bioink design, ranging from natural and synthetic hydrogels to composite and reinforced systems, such as the emerging attapulgite-polyvinyl alcohol platform, as well as stimulus-responsive smart materials. These materials are being developed to better replicate the biochemical and mechanical properties of the native extracellular matrix while maintaining suitable printability. Second, the review discusses the principles, optimization strategies, and application characteristics of major bioprinting techniques, including extrusion-based, photocuring-based, inkjet, and microfluidic bioprinting, with particular emphasis on balancing printing fidelity, structural complexity, and cell viability. In addition, it examines key strategies for promoting functional maturation and in vivo integration of cartilage organoids, including coculture systems, direct vascularization approaches, spatiotemporally controlled delivery of growth factors, dynamic mechanical stimulation, and emerging osteoimmunomodulatory interventions such as macrophage polarization and neutrophil extracellular trap clearance. Despite substantial advances, several critical challenges remain, including limited biomimetic accuracy in hierarchical architecture, instability of long-term cell phenotype, difficulties in vascularizing large-scale constructs, and the absence of standardized criteria for clinical translation. By identifying these bottlenecks and outlining future directions, including the development of 4D bioprinting materials and the integration of organ-on-a-chip systems with artificial intelligence-based optimization, this review aims to support the evolution of cartilage organoids from structural mimics toward truly functional regenerative constructs, ultimately facilitating their translation into clinically applicable therapies.

Currently, the development of multifunctional scaffolds that synergistically promote osteogenesis and angiogenesis remains a significant challenge in bone tissue engineering. It is increasingly recognized that scaffolds composed of a single material or possessing a single function are often inadequate, as they fail to mimic the complex biochemical and physical microenvironments. In this study, we successfully fabricated a submicro/nanofibrous membrane using electrospinning technology, which creates a biomimetic extracellular environment through a polycaprolactone (PCL) / gelatin (GEL) matrix. The incorporation of attapulgite (ATT) supplies essential osteogenic ions, while γ-iron oxide (γ-Fe2O3) facilitates mesenchymal cell differentiation and imparts magnetic responsiveness. Co-culturing the membranes with human umbilical vein endothelial cells (HUVECs) and bone marrow mesenchymal stem cells (BMSCs) revealed that the membranes possessed strong biocompatibility and promoted osteogenic differentiation and angiogenesis. Both in vivo and in vitro studies suggested the involvement of the BMP2-Smad‑RUNX‑2 signaling axis in the effects of the PG/ATT/γ‑Fe2O3 scaffold, which also upregulated osteogenesis‑related gene expression under a magnetic field. This work offers new insights and provides a scientific foundation for advancing the use of functionalized nanomaterials in the field of bone tissue engineering.

In order to overcome the poor mechanical properties and low permeation flux of MXene nanosheets, as well as the easy agglomeration and limited adsorption capacity of attapulgite (ATP), a composite membrane material (Fe-Co/MXene-ATP) was prepared by vacuum filtration method, of which ATP was inserted into the stacking layers of MXene and bimetallic oxides were loaded as active substances. Through a series of characterization and experiments, it was proved that MXene-ATP composite membrane was achieved, and Fe and Co oxides were successfully loaded on it. The membrane material was used to remove methylene blue (MB). Under the optimal experimental conditions, the removal ratio of MB can reach over 90%, the MB flux is 1.94 mL· cm-2·min-1. The removal mechanisms of Fe-Co/MXene-ATP membrane materials for MB were clarified through comparative experiments and free radical capture, and their mechanisms mainly included MXene-ATP bifunctional substrate for synergistic bimetallic catalysis, the MXene confinement effect enhancing catalytic efficiency and stability, and the "adsorption-catalysis-filtration" trinity dynamic removal mechanism. LC-MS was employed to identify the intermediate products generated during MB degradation, and the potential degradation pathways were subsequently deduced.

The antagonistic environmental geochemical behaviors of cadmium (Cd) and arsenic (As) present a critical challenge for the simultaneous remediation of contaminated paddy soils. Here, we report the synthesis of attapulgite-supported nanoscale zero-valent iron (ATP-nZVI), and its remediation performance was systematically investigated. Batch adsorption kinetics studies showed that ATP-nZVI material exhibits superior adsorption capacity performance for Cd and As compared with its individual components. Importantly, the pot experiment demonstrated that ATP-nZVI application significantly increased soil pH and iron content, while concurrently enriching the soil microbiome, especially iron- and arsenic-reducing bacteria. This synergistic Fe-microbe interaction stimulated iron cycling, effectively reducing the bioavailability of Cd and As and promoting the formation of iron plaques in rice roots. Consequently, ATP-nZVI treatment decreased Cd and As accumulation in rice grains by 86.49% and 19.15%, respectively, while enhancing grain yield and essential micronutrient profiles (Zn, Mn, Cu, Fe and Mg). This work offers a cost-effective, eco-friendly and sustainable remediation strategy for the integrated management of multi-heavy metal contaminated agricultural soils.

Developing remediation agents that are both highly efficient and environmentally compatible remains a major focus for mitigating hexavalent chromium (Cr(VI)) contamination, particularly in mining-impacted soils. In this study, bentonite (Bent), attapulgite (ATP), and diatomite (DE) were modified with APTES, and solution-phase screening identified amine-modified bentonite (NH2-Bent) as the best-performing agent, achieving a Cr(VI) removal efficiency of 95.3% was amine-modified bentonite (NH2-Bent). Multidimensional structural and electrochemical analyses showed that the bentonite interface changed from anion-repulsive to highly electropositive with reduced electron-transfer resistance due to amine modification. This interfacial transformation shifted Cr(VI) removal from diffusion-limited adsorption toward adsorption-assisted interfacial processes involving enhanced electron exchange. Density functional theory calculations indicated that the introduction of amine groups strengthened Cr(VI) binding at the mineral interface and facilitated directional electron transfer from amine nitrogen atoms to chromium species. When applied to Cr(VI)-contaminated mining soils, NH2-Bent reduced Cr(VI) bioavailability by 92.8% at a 3% amendment rate, markedly outperforming unmodified bentonite, while promoting the recovery of soil biochemical functions, as evidenced by increases in urease and sucrase activities by 157.1% and 102.2%, respectively. Therefore, NH2-Bent emerges as a promising and environmentally compatible mineral amendment for mitigating Cr(VI) contamination in mining soils.

The mismatch between nutrient release from organic fertilisers and crop nitrogen demand often results in low nitrogen use efficiency and substantial nitrogen losses. To address this issue, a pot experiment was conducted to assess the effects of co-applying magnetite or attapulgite modified biochar with organic fertiliser on soil nitrogen transformation, microbial community structure, and rapeseed growth. The results showed that both mineral-modified biochar composites effectively improved soil nitrogen dynamics. The 5% magnetite modified biochar treatment performed best, increasing rapeseed yield to 1200 kg·ha-1, along with superior plant height, root length, and chlorophyll content. Soil analysis revealed that magnetite enhanced the retention of ammonium and nitrate, whereas attapulgite promoted adsorption and delayed nitrogen release through its porous structure. Microbial analysis showed that magnetite increased the abundance of Bacillota and upregulated ammonia-oxidising bacterial (AOB) genes, thereby enhancing nitrification. In contrast, attapulgite modified biochar regulated the abundance of Pseudomonadota and upregulated the nosZ gene, thereby optimising denitrification and mitigating nitrogen losses. This study provides theoretical and practical insights into the use of mineral modified biochar composites as nitrogen enhancers for sustainable agriculture.

Water scarcity, nutrient loss, and heavy metal contamination pose intertwined challenges to sustainable agriculture in arid and semi-arid regions. Despite advances in superabsorbent polymers (SAPs), few studies have integrated water retention, nutrient conservation, and pollutant immobilization into a single material platform using regionally abundant waste biomass and raw clay-both unmodified. Herein, we report a low-cost, green multifunctional superabsorbent composite (CFPAA/ATPs) synthesized via room-temperature, one-pot free-radical polymerization without inert gas protection, using Caragana fiber (CF), natural attapulgite clay (ATP), and acrylic acid (AA). The optimized composite (CFPAA/ATP-4) exhibits an equilibrium water absorption of 831.1 g/g in deionized water and 65.1 g/g in 0.9 wt% NaCl solution. It also shows rapid swelling kinetics across various media (different pH values, fertilizer solutions, salt solutions, and surfactant solutions) and maintains good cyclic stability over six cycles. Soil column experiments demonstrate that CFPAA/ATP-4 significantly enhances water and nutrient retention in sandy soil while effectively immobilized Pb[2+] and Cd[2+]. Pot trials with soybean seedlings further confirm improved survival rates, plant height, and biomass accumulation in both shoots and roots. In summary, CFPAA/ATPs represent an eco-friendly, multifunctional material that integrates efficient water absorption, fertilizer retention, and pollution control into a single system, showing great potential for alleviating soil drought, enhancing fertilizer utilization, and promoting sustainable agricultural development in arid regions.

In order to achieve a green, efficient, and stable removal of U(VI) from the leachate of U(VI) tailings, this study employs 3-aminopropyltriethoxysilane (APTES) as a modifying agent to ammoniate and modify attapulgite (ATP), ultimately, hydroxyapatite (HAP) is loaded onto the modified ATP to prepare a novel composite material (APTES/ATP@HAP),the study systematically explores the efficacy and mechanism of U(VI) extraction using APTES/ATP@HAP. The results indicate that under the conditions of pH= 4.0, T = 298.15 K, and t = 12 h, the maximum adsorption capacity of APTES/ATP@HAP for U(VI) reaches as high as 2128.72 mg·g[-1],this capacity is 2.61 times greater than that of HAP directly modified with amino group and 5.57 times that of ATP directly amino group functionalized, it is worth noting that APTES/ATP@HAP can remove 99.11% of U(VI) in actual wastewater when the dosage is 0.8 g ·L[-1], after five times of recycling, the removal rate of U (VI) by APTES /ATP@HAP can still reach 99.06%. Promoting the release of phosphate in HAP through amino-triggered micro acidity is crucial for the formation of autunite,this work develops a new composite material for the efficient immobilization of U (VI) in water and the mechanism of amino deprotonated local acidic microenvironment promoting the formation of autunite was elucidated.

Low-concentration organic pollutants (e.g., antibiotics) challenge conventional Fenton oxidation due to slow kinetics and matrix interference. Herein, a Cu-doped natural iron-containing attapulgite (Cu-ATP) with dual Fe-Cu active sites was developed for synergistic adsorption and in situ Fenton-like oxidation. The optimized Cu-ATP 2/3 exhibited a high adsorption capacity (96.36 mg g-1) toward tetracycline hydrochloride (TCH) and enhanced oxidation kinetics (apparent rate constant: 0.0143 min-1), outperforming many reported metallic catalysts. Mechanistic results indicate that Cu incorporation improves the mesoporous structure for pollutant enrichment and promotes the Fe(III)/Fe(II) redox cycle via electronic modulation. Meanwhile, the Cu(II)/Cu(I) cycle, driven by H2O2 and •O2H, sustains catalytic activity, while •OH adsorbed on the surface achieves in situ Fenton oxidation of pollutants. The Cu-ATP/H2O2 system operates over a wide pH range (3.3-9.7) and shows strong resistance to coexisting ions (e.g., Cl-, NO3-, SO42-, and H2PO4-) and humic acid. Continuous fixed-bed experiments demonstrated stable TCH removal (>85% over 250 L) with negligible metal leaching (<1 mg L-1). This work establishes a Cu-enhanced dual-site redox cycle strategy for coupled adsorption-oxidation, offering actionable mechanistic insights for designing high-efficiency, sustainable catalysts and underscoring the practical viability of integrated adsorption-oxidation systems for real wastewater remediation.

Industrialization has elevated hexavalent chromium (Cr(VI)) contamination in soil and groundwater. While vertical cutoff walls are common remediation tools, the influence of hydraulic gradients on contaminant transport within these barriers remains inadequately studied. This investigation systematically examines Cr(VI) migration through cement-attapulgite cutoff walls under varying hydraulic gradients (10-40) via laboratory experiments. Results demonstrate that molecular diffusion consistently dominates over mechanical dispersion in Cr(VI) transport across this gradient range. Although mechanical dispersion and convection intensify with increasing gradients, adsorption persists as the primary migration mechanism. Analysis incorporating diffusion reveals that dispersivity is independent of seepage velocity, whereas the hydrodynamic dispersion coefficient increases and the retardation factor decreases with rising velocity. Based on these relationships, a predictive model is proposed for estimating the Cr(VI) retardation factor under different seepage velocities. Furthermore, a Cr(VI) migration model utilizing Hydrus software was developed to evaluate wall performance under diverse hydraulic heads. These findings elucidate fundamental transport mechanisms and provide critical predictive tools, enhancing the understanding and application of cutoff wall technology for Cr(VI) containment.

Two biochar-based adsorbents, namely, original corn cob biochar and attapulgite-biochar composite, were prepared via two-step pyrolysis at 400 and 700 °C under oxygen deficiency for petroleum hydrocarbon removal from water. Experimental results revealed that attapulgite modified the structure of biochar, increased the quantity of surface functional groups, and thereby significantly enhanced its adsorption capacity. Petroleum hydrocarbon adsorption experiments showed that adsorption kinetics was more accurately characterized by the pseudo-second-order model and isothermal adsorption was characterized by the Freundlich model, supported by R [2] and error analysis. This finding suggested that chemisorption through multimolecular layers was the predominant mechanism of adsorption. Regarding the effect of pH, the original biochar exhibited maximum adsorption capacity under weakly acidic conditions (pH 5.0), while the attapulgite-biochar composite achieved optimal adsorption performance in neutral to weakly alkaline environments (pH = 7.0-9.0), and attapulgite-biochar composite exhibited an adsorption rate 41.8% higher than that of the original biochar. In terms of salinity, it exerted a notable influence on the adsorption capacity of biochar; however, the attapulgite-biochar composite demonstrated superior adaptability over a wider salinity range (0.5% to 8.0%) and a 65.14% increase in overall adsorption efficiency compared to the original biochar. Gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy indicated that the adsorption mechanism primarily encompassed surface adsorption, interfacial adsorption, micropore filling, hydrogen bonding, π-π bond interactions, and chelation effects. Additionally, specific redox reactions might have occurred alongside the adsorption process. In conclusion, this low-cost, environmentally friendly, and highly efficient carbon material holds considerable promise for the removal of oil pollutants in saline-alkali environments.

Iron (Fe) deficiency in alkaline soils severely constrains crop productivity, threatening global food security and resilience. This study reports the synthesis of an iron sulfide-palygorskite nanohybrid (FeS-S2-@Pal) infused with equimolar sulfide ions to create a reducing environment that enhances Fe2+ stability and uptake in soybean. Structural characterization confirmed stability, while controlled-release kinetics (kh = 0.036) indicated prolonged Fe2+ retention compared to FeS@Pal (kh = 0.049). Pot experiments in alkaline soil (3.15 mg kg-1) showed improvements in germination (12.9%), dry biomass (16.6%), vigor (31.6%), and Fe assimilation (shoots 30%, roots 60%), along with higher chlorophyll (23.2%) and carotenoids (30.0%). Enhanced antioxidant enzymes (SOD, CAT, APX, POD, PPO) and nonenzymatic antioxidants (phenolics, flavonoids, proteins, DPPH, ABTS) indicated effective oxidative stress mitigation. Sulfide incorporation stabilized Fe2+, promoting efficient nutrient assimilation and physiological performance. Thus, FeS-S2-@Pal represents a sustainable, redox-active nanofertilizer that supports the energy-food-water nexus and strengthens agricultural resilience under environmental stress.

Soils in and around mining areas are frequently co-contaminated with heavy metals, posing risks to crop safety and human health. Nano zero-valent iron (nZVI) shows promise for multi-metal stabilization but is hindered by aggregation and oxidation. In this study, nZVI-supported attapulgite (nZVI@A) was synthesized by liquid-phase reduction and evaluated for stabilization of Cd, Cr, Cu, Ni, Pb, and Zn in contaminated mine soil and for reduction of maize metal uptake. Pot trials and stabilization tests were conducted, during which extractable fractions, sequential speciation, soil pH, CEC, EC, and metal concentrations and translocation in maize tissues were measured. Experimental results indicated that the stabilization effect was optimal at an nZVI-to-attapulgite mass ratio of 1:3. Significant reductions in extractable concentrations were observed for all target metals, with decreases in acid-extractable fractions and increases in residual fractions, indicating conversion to more stable forms and reduced bioavailability. Metal accumulation and translocation factors in maize were markedly lowered. The stabilization effect was attributed to synergistic adsorption by attapulgite and nZVI-driven precipitation and redox transformations. NZVI@A is proposed as a promising, potentially scalable in-situ amendment for multi-metal immobilization; field-scale validation and long-term stability assessment are recommended.

Landfill leachate commonly contains mixed contaminants in which heavy metals coexist with organic acid, potentially altering the chemical attenuation and interfacial stability of vertical cutoff wall backfills. In this study, ZnCl2 and butyric acid were selected as representative inorganic and organic solutes. A fluidity test determined an appropriate dredged sediment-attapulgite backfill proportion of attapulgite:water:dredged sediment = 31:36:33. Equilibrium batch adsorption tests and isotherm fitting were conducted for single and mixed solutes, and zeta potential was measured to probe interfacial electrical responses. Under single-solute conditions, Zn[2+] showed capacity-limited retention consistent with the Langmuir model, with qmax = 23,617 mg/kg; Zn[2+] removal exceeded 90% at ZnCl2 ≤ 800 mg/L and remained above 80% at 1000 mg/L, whereas butyric acid removal stayed at 30%-40%. Under coexistence, interactions were strongly asymmetric: butyric acid substantially suppressed Zn[2+] retention, while ZnCl2 had a weaker effect on butyric acid removal. At 40,000 mg/L butyric acid, the apparent Zn[2+] qmax decreased to 3132.59 mg/kg, corresponding to an effective capacity derating of 0.13 relative to the no-organic case, indicating that single-solute parameters can be nonconservative in environments enriched with organic acids. Zeta potential results further showed reduced magnitudes, especially with butyric acid, implying weakened electrostatic repulsion that may promote aggregation and microstructural rearrangement under seepage. These findings support compatibility screening and conservative parameter selection for dredged sediment-attapulgite cutoff wall backfills in leachate enriched with organic acids.

Heat stress (HS) poses a significant stress challenge to growing lambs, impacting growth performance, health, and physiological responses. The study evaluated feeding an essential oil blend (EOB) on growth performance, physiological and blood parameters, oxidative, and immune responses. Thirty-two 3 mo old female (BW 18.6 ± 2.43 kg) crossbred (Mongolian × Thin-tailed Han F1) lambs were randomly assigned to either: (1) control (CON)-grain mix without EOB; or (2) EOB-an EOB blend supplemented at 4 g/kg grain mix. The EOB blend was comprised of 4.34% Zanthoxylum, 1% capsicum, and 1.06% cinnamon oils with 93.6% attapulgite carrier containing linalool, sabinene, limonene, capsaicin, cinnamaldehyde and eugenol. Extreme heat stress occurred for 39 out of the 45 d experiment. Feeding HS lambs EOB increased (p < 0.05) ADG (107.4 and 162.0 g/d for CON and EOB, respectively), forage intake (239.2 and 287.0 g/d), DMI (863.1 and 930.2 g/d), and feed efficiency (0.123 and 0.181 ADG, g/DMI, g) compared with lambs fed CON. Feeding EOB reduced (p < 0.01) respiration rates (RR) and rectal (RT) and skin temperatures (ST) compared to CON-fed lambs. Lambs fed EOB had a higher T-SOD activity and IgM concentration (0.05 < p < 0.10) than CON-fed lambs. Growing heat-stressed lambs fed EOB demonstrated a lower (p < 0.05) eosinophil percentage. Feeding EOB ameliorated HS conditions for growing crossbred lambs, which demonstrate improved growth performance, enhanced physiological responses, and overall health status.