Aluminum Hydroxide Nanoparticles Research Articles

Direct 3D printing of triple-responsive nanocomposite hydrogel microneedles for controllable drug delivery

Hydrogel microneedle patches have emerged as promising platforms for painless, minimally invasive, safe, and portable transdermal drug administration. However, the conventional mold-based fabrication processes and inherent single-functionality of such microneedles present significant hurdles to broader implementation. Herein, we have developed a novel approach utilizing a precursor solution of robust nanocomposite hydrogels to formulate photo-printable inks suitable for the direct 3D printing of high-precision, triple-responsive hydrogel microneedle patches through digital light processing (DLP) technology. The ink formulation comprises four functionally diverse monomers including 2-(dimethylamino)ethyl methacrylate, N-isopropylacrylamide, acrylic acid, and acrylamide, which were crosslinked by aluminum hydroxide nanoparticles (AH NPs) acting as both reinforcing agents and crosslinking centers. This results in the formation of a nanocomposite hydrogel characterized by exceptional mechanical strength, an essential attribute for the 3D printing of hydrogel microneeedle patches. Furthermore, this innovative 3D printing strategy facilitates facile customization of microneedle geometry and patch dimensions. As a proof-of-concept, we employed the fabricated hydrogel microneedles for transdermal delivery of bovine serum albumin (BSA). Importantly, these hydrogel microneedles displayed no cytotoxic effects and exhibited triple sensitivity to pH, temperature and glucose levels, thereby enabling more precise on-demand drug delivery. This study provides a universal method for the rapid fabrication of hydrogel microneedles with smart responsiveness for transdermal drug delivery applications.

Rheological properties of fluorine-free foams stabilized by aluminum hydroxide nanoparticles and mixture of siloxane and hydrocarbon surfactants

Fluorine-free foam stabilized by nanoparticle (NP) is expected to become a new generation of environmental-friendly firefighting foam. Many problems on properties of NP-stabilized fluorine-free foams remain to be studied. The present paper focuses on the rheology and foam stability of fluorine-free foam stabilized by aluminum hydroxide NPs. The surface tension, conductivity, foamability, viscosity, and viscoelasticity of mixed dispersions were measured. The stability, viscosity, viscoelasticity, and thixotropy of foam was analyzed deeply by model fitting and mechanism explanation. The results show that the rheological properties and foam stability of mixed dispersions are both enhanced by the presence of NPs, and the enhancement amplitude increased with NP concentration. Both dispersions and NP-stabilized foams exhibit shear thinning behavior, and the viscosity variations in dispersions conform to the Cross model well. As NP concentration increases, the linear viscoelastic range of foam becomes wider, the flow point of NP foam is delayed, demonstrated enhanced viscoelasticity. The thixotropic recovery of foam decreases with the increasing NP concentration, and foam thixotropic recovery decreases with the increase of irreversible deformation degree. This study can provide design idea for the development of fluorine-free firefighting foam.

A comparative study on the influence of MWCNT, GO, and Al(OH)3 gel matrix modification on hierarchical structured composite reinforced with needle-punched jute fiber and glass fiber

The main objective of this paper was to identify the influence of different filler materials on the properties of hybrid composites. The hybrid composites were fabricated using randomly oriented glass fiber mats, needle-punched jute fiber mats, and epoxy resin as the matrix material. Three different kinds of filler materials were studied: Multi-Walled Carbon Nanotubes (MWCNTs), Graphene Oxide (GO), and Aluminum Hydroxide (AlOH) nanoparticles. The secondary reinforcements were dispersed in the epoxy matrix through ultrasonication. The composites were made by conventional hand lay-up followed by applying high pressure and temperature under a hydraulic press to effectively cure and minimize voids within the final composite. These were compared with the properties of the unmodified composite containing no filler. The influence on mechanical properties was evaluated through tensile, flexural, and impact tests. Failure modes of the fractured tensile specimen were observed through Scanning Electron Microscopy (SEM). Fourier Transform Infrared (FTIR) analysis was done to observe the changes in the chemical structure upon the addition of secondary reinforcements. Lastly, water absorption behavior and flame retardancy were observed as well. The results showed that MWCNT resulted in the composite exhibiting superior properties and GO, on the contrary, led to the deterioration of the properties. This could be because an optimum concentration of MWCNT was used, whereas this was not the case for GO filler. The addition of MWCNT resulted in a more substantial but brittle composite, while AlOH enhanced the ductility of the composite by compromising the overall strength. Hence, it can be concluded that MWCNT resulted in the formation of composites with the most desired properties.

Immunogenicity of different nanoparticle adjuvants containing recombinant RBD coronavirus antigen in animal model.

Ongoing mutations of SARS-CoV-2 present challenges for vaccine development, promising renewed global efforts to create more effective vaccines against coronavirus disease (COVID-19). One approach is to target highly immunogenic viral proteins, such as the spike receptor binding domain (RBD), which can stimulate the production of potent neutralizing antibodies. This study aimed to design and test a subunit vaccine candidate based on the RBD. Bioinformatics analysis identified antigenic regions of the RBD for recombinant protein design. In silico analysis identified the RBD region as a feasible target for designing a recombinant vaccine. Bioinformatics tools predicted the stability and antigenicity of epitopes, and a 3D model of the RBD-angiotensin-converting enzyme 2 complex was constructed using molecular docking and codon optimization. The resulting construct was cloned into the pET-28a (+) vector and successfully expressed in Escherichia coli BL21DE3. As evidenced by sodium dodecyl-polyacrylamide gel electrophoresis and Western blotting analyses, the affinity purification of RBD antigens produced high-quality products. Mice were immunized with the RBD antigen alone or combined with aluminum hydroxide (AlOH), calcium phosphate (CaP), or zinc oxide (ZnO) nanoparticles (NPs) as adjuvants. Enzyme-linked immunosorbent assay assays were used to evaluate immune responses in mice. In-silico analysis confirmed the stability and antigenicity of the designed protein structure. RBD with CaP NPs generated the highest immunoglobulin G titer compared to AlOH and ZnO after three doses, indicating its effectiveness as a vaccine platform. In conclusion, the recombinant RBD antigen administered with CaP adjuvant NPs induces potent humoral immunity in mice, supporting further vaccine development. These results contribute to ongoing efforts to develop more effective COVID-19 vaccines.

Energy generation from waste packaging plastic via thermo-catalytic pyrolysis using catalysts produced from spent aluminum hydroxide nanoparticles

Energy generation from waste packaging plastic via thermo-catalytic pyrolysis using catalysts produced from spent aluminum hydroxide nanoparticles

Aluminum hydroxide nanoparticle adjuvants can reduce the inflammatory response more efficiently in a mouse model of allergic asthma than traditional aluminum hydroxide adjuvants.

Traditional aluminum hydroxide is widely used as a vaccine adjuvant. Despite its favorable safety profile, it can cause an inflammatory response at the injection sites. However, multiple studies have shown that aluminum hydroxide nanoparticles have more potent adjuvant activity than their traditional aluminum hydroxide counterparts as antigen carriers; it has also been found that the local inflammation caused by aluminum hydroxide nanoparticle adjuvants is milder than that of other adjuvants. The aim of the present study was to compare the degree of inflammatory response between the aluminum hydroxide nanoparticle adjuvants and the traditional aluminum hydroxide adjuvants in the desensitization treatment of a mouse model of house dust mite (HDM)-induced allergic asthma. Mice were sensitized intraperitoneally with HDM. Subcutaneous desensitization was performed with PBS, traditional aluminum hydroxide adjuvants and aluminum hydroxide nanoparticle adjuvants. The mice were challenged and subsequently euthanized. The skin tissue at the local injection sites was assessed and specific indices were measured, such as the response of specific immunoglobulins, the airway hyper-responsiveness (AHR), and the inflammation in the bronchoalveolar lavage and lung tissues. Early hypersensitivity responses were suppressed in mice treated with subcutaneous immunotherapy (SCIT). Both traditional aluminum hydroxide-SCIT and aluminum hydroxide nanoparticle-SCIT could inhibit AHR. However, aluminum hydroxide nanoparticle-SCIT was able to significantly inhibit the secretion of eosinophils in the lung tissue and the production of type 2 cytokine Interleukin (IL)-5 in blood compared with the corresponding effects noted by traditional aluminum hydroxide adjuvants. Moreover, the aluminum hydroxide nanoparticle group reduced the inflammatory response at the local injection site. Collectively, the data indicated that allergen-specific immunotherapy using aluminum hydroxide nanoparticle adjuvants reduces lung and local inflammation compared with traditional aluminum hydroxide adjuvants.

Evaluation of Aluminium Hydroxide Nanoparticles as an Efficient Adjuvant to Potentiate the Immune Response against Clostridium botulinum Serotypes C and D Toxoid Vaccines.

Clostridium botulinum serotypes C and D cause botulism in livestock, a neuroparalytic disease that results in substantial economic losses. Vaccination with aluminium-based toxoid vaccines is widely used to control the spread of botulism. Aluminium-based adjuvants are preferred owing to their apparent stimulation of the immune responses to toxoid vaccines when compared to other adjuvants. The aim of our study was to evaluate aluminium hydroxide nanoparticles as a potential substitute for alhydrogel in the botulism bivalent vaccine. Botulism vaccines were formulated with either alhydrogel or nanoalum and comparative efficacy between the two formulations was conducted by evaluating the immune response in vaccinated guinea pigs. A significant increase in immunological parameters was observed, with the antibody titres higher in the serum of guinea pigs (20 IU/mL of anti-BoNT C/D) injected with nanoalum-containing vaccine than guinea pigs inoculated with the standard alhydrogel-containing vaccine (8.7 IU/mL and 10 IU/mL of anti-BoNT C and anti-BoNT D, respectively). Additionally, the nanoalum-containing vaccine demonstrated potency in a multivalent vaccine (20 IU/mL of anti-BoNT C/D), while the standard alhydrogel-containing vaccine showed a decline in anti-BoNT C (5 IU/mL) antibody titres.

Mechanical Performance of Glass/Epoxy Composites Loaded with Silane-Treated Aluminum Hydroxide Fillers.

This study investigates the influence of silane-treated aluminum hydroxide on the mechanical performance of flame-retardant composites. These composites have potential applications for luggage bags, as a replacement for conventional plastics, offering more durability and lighter weight. Glass fabric was used as the reinforcement, while epoxy was used as the matrix material. To impart flame retardancy, aluminum hydroxide nanoparticles were used as fillers in different weight % age (5%, 10% and 15%). As these are inorganic particles and have compatibility issues with the matrix material, silane-coupling agents (Dynasylan® 6490 and Dynasylan Glymo) were used to treat these filler particles. Both the silane-coupling agents fraction used for treatment and the fillers fraction added to the composites were varied to determine the most optimum combination. The mechanical properties of the developed composites such as tensile, flexural, and short beam shear strength were investigated. The best results were exhibited by 10% aluminum hydroxide fillers treated with 1% (by weight) coupling agent (Dynasylan Glymo).

Experimental investigations of aluminum hydroxide nanoparticles on properties of cementitious composites using macro and micro scale tests

The potential to use nanomaterials to produce high-performance cementitious composites is gradually developing. This study designed novel cementitious composites containing aluminum hydroxide nanoparticles (AHNPs), considering features such as amphoterism, functional groups, and compatibility with cement components. The percolation threshold of the AHNP dosage in cementitious composites was calculated as 0.5% by weight replacing cement, and cementitious composites containing 0.5% wt. AHNP have 1.11- and 1.94-fold greater compressive and flexural strength than plain cementitious composites, respectively. AHNPs increased the portlandite content and decreased the calcite content due to redox reactions and the formation of dmitryivanovite in the cement matrix. Compared with plain paste, the application of hybrid 0.3% wt. AHNPs and 0.1% wt. GO increased the compressive strength by 92.55%, flexural strength by 83.74%, fracture toughness by 5.29%, and calcite content by 35.38%. This combination also achieved increases of 72.38% in compressive strength, 18.23% in flexural strength, 10.91% in fracture toughness, and 5.18% in calcite content compared to cementitious composites modified with 0.1% wt. GO. GO and AHNPs generated a more compact structure due to their mutual hydrogen bonding capacity and thus enhanced the macro- and micro properties of cementitious composites by facilitating hydration.

A strong soybean meal adhesive enhanced by aluminum hydroxide nanoparticles via a low-cost and simple organic-inorganic hybrid strategy

Soybean meal (SM), as a byproduct of bean oil production, used to develop formaldehyde-free bio-adhesives to solve the formaldehyde release problem in the wood industry is very meaningful. However, the low water resistance and weak adhesion stability of SM-based adhesives limited their application and development. In this study, inspired by nacre and mussel byssus, a novel organic-inorganic hybrid system was formed by introducing Al(OH)3 nanoparticles into SM adhesive. Al(OH)3 nanoparticles interacted with SM to form dense noncovalent crosslinking network based on hydrogen and coordination bonds, enhancing the adhesion performance and water resistance of SM adhesive. The dry and wet shear strength of the SM/Al adhesive were improved to 1.75 MPa and 1.25 MPa, respectively. Meanwhile, the hydrogen and coordination bonds served as sacrificial bonds, which promoted dissipating energy and caused the toughness of SM/Al adhesive to improve by 133.3% to 11.2 MJ/m3. In addition, the dehydration process of Al(OH)3 nanoparticles reduced the heat release of the adhesive combustion and improved adhesive flame retardancy. Therefore, the SM/Al adhesive showed a comprehensive improvement in adhesion strength, toughness, water resistance, and flame retardancy performances. This work provides a novel strategy for preparing strong, eco-friendly, multiple performances and low cost SM adhesives.

Facile preparation of fatty acids/nano [Al(OH)3/Al2O3]/wool fabric introducing thermal energy management with multifunctional properties

Development of facile fabrication of thermal energy storage for diverse purposes has become essential to improve energy efficiency. In this regard, for the first time, fatty acids/nano Al-based/wool composite was prepared by a simple one-step procedure through in situ formation. The treated fabric was characterized by FT-IR, Raman, XRD and SEM. DSC, TGA and thermal conductivity were conducted to investigate thermal behavior of the treated wool. The experimental results show the appropriate melting and solidifying temperature, 36.59 and 29.58 °C with responding enthalpies 59.22 and 52.08 J/g, respectively, for the desired application. TGA revealed the relatively improvement in thermal durability of the treated wool fabric. Embedding Al(OH)3/Al2O3 nanoparticles in eutectic phase change materials results in a 104.16 % increase in thermal conductivity. Despite the negative effect of fatty acids on flame retardant feature of the composite, aluminum hydroxide nanoparticles incorporated into the prepared composites imparted a good smoke suppression to the prepared composite. Moreover, the optimal sample illustrated excellent antibacterial and anti-fungal effects. The finished fabric also showed good activity for degradation of methylene blue under daylight irradiation. The treatment also greatly increased the water absorption of the composite and shrinkage resistance and also decreased alkali solubility. As a result, this thermos-regulative simple approach has a potentiality to be applied in various textile materials for diverse industries.

Adsorption behavior of cationic surfactant onto aluminum hydroxide nanoparticles and application in lindane removal

Adsorption behavior of cationic surfactant onto aluminum hydroxide nanoparticles and application in lindane removal

Immunization of mice with chimeric protein-loaded aluminum hydroxide and selenium nanoparticles induces reduction of Brucella melitensis infection in mice.

Due to the many problems with commercially available vaccines, the production of effective vaccines against brucellosis is a necessity. The aim of this study was to evaluate the immune responses caused by the chimeric protein consisting of trigger factor, Bp26, and Omp31 (TBO) along with aluminum hydroxide (AH/TBO) and selenium (Se/TBO) nanoparticles (NPs) as adjuvants in mouse model. Recombinant antigen expression was induced in Escherichia coli BL21 (DE3) bacteria using IPTG (isopropyl-d-1-thiogalactopyranoside). Purification and characterization of recombinant protein was conducted through NiFe3O4 NPs, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot. NP characteristics, including morphology and particle size, were measured in vitro. The recombinant TBO was loaded on to AH and Se NPs and were administered subcutaneously. After mice immunization, measurement of antibody titter and protection assay was performed. The average sizes of AH and Se NPs were about 60 nm and 150 nm, respectively. The enzyme-linked immunosorbent assay results showed that the serum of mice immunized by subcutaneous injection with both nanovaccines produced significant immunoglobulin G (IgG) responses against the chimeric antigen. The results of TBO-specific IgG isotype (IgG2a/IgG1) analysis showed that both AH and Se NPs induced a type to T-helper immune response. In addition, the results of the challenge with the pathogenic strain of Brucella melitensis 16M showed that vaccinated mice with AH/TBO NPs indicated a higher reduction of bacterial culture than immunized mice with Se/TBO NPs and TBO alone. The results showed that AH NPs carrying chimeric antigen can be a promising vaccine candidate against brucellosis by producing protective immunity.

Flame-Retardant Nanocomposite Polymeric Materials Based on High-Density Polyethylene and Aluminum Hydroxide Nanoparticles

Flame-Retardant Nanocomposite Polymeric Materials Based on High-Density Polyethylene and Aluminum Hydroxide Nanoparticles

Immunopotential of Pasteurella multocida bivalent outer membrane protein-based vaccine entrapped in aluminum hydroxide nanoparticles.

Swine pasteurellosis is one of the most economically important diseases of pig caused by Pasteurella multocida (P. multocida) capsular types A and D. These organisms are commensals and opportunistic pathogens in the upper respiratory tract in pig. In the present study, we extracted whole outer membrane proteins (OMP) from P. multocida capsular types A and D and were mixed together in the ratio of 1:1 forming bivalent outer-membrane proteins. The bivalent OMP was adsorbed onto aluminum hydroxide nanoparticles. The size of aluminum hydroxide nanoparticles adsorbed outer membrane protein was found to be in the range of 125 to 130nm. We observed that aluminum hydroxide nanoparticles adjuvanted bivalent OMP-based vaccine elicited quicker immune kinetics in terms of IgG response as compared to aluminum hydroxide microparticles adjuvanted bivalent bacterin vaccine against P. multocida capsular type A and D.

Evaluation of the Toxic Effects of Aluminum Hydroxide Nanoparticles as Adjuvants in Vaccinated Neonatal Mice.

Aluminum hydroxide nanoparticles have been employed in many industries, which are widely abundant in many aspects of human life. The role of the aluminum hydroxide nanoparticles adjuvant is to enhance the immune response. However, the impact of nanoparticles exposure has not been perfectly investigated yet. Accordingly, some questions have been raised about their potentially harmful effects, based on which the current research aims to answer them. This study aimed to investigate the histological effects of aluminum hydroxide nanoparticles and bulk-aluminum hydroxide (bulk Al[OH]3) on the liver, lung, heart, and kidney tissues. For this reason, an experiment was implemented on the aluminumhydroxide nanoparticles adjuvant in five neonatal mice. Intramuscularly, the mice were injected with 0.125 mL of adjuvanted vaccine, while five neonatal mice were injected with bulk and nanoparticles of Al (OH)3 and then sacrificed after one and two months, respectively. Vaccines were controlled by evaluating the histopathological response in neonatal mice. Subsequently, the pathological effect of both adjuvants was surveyed using the histological study of the lung, liver, heart, and kidney of the animals. The obtained recorded data indicated that both types of vaccine adjuvants caused pathological lesions on the histology sections of the liver, lung, heart, and kidney tissues. Moreover, bulk Al (OH)3 adjuvant vaccine was more effective and had a higher pathological response than aluminum hydroxide nanoparticles adjuvant vaccine. In addition, the total DNA content in both groups was estimated using Fluorometer from Promega. Compared to aluminum hydroxide nanoparticles groups, the tissues indicated a decrease in total DNA content obtained in bulk Al (OH)3 groups. Therefore, it can be concluded that the exposure to aluminum hydroxide nanoparticles would result in less pronounced toxicity, as well as systemic inflammation, compared to the bulk Al (OH)3 aluminum hydroxide.

Synthesis of UV/blue light-emitting aluminum hydroxide with oxygen vacancy and their application to electrically driven light-emitting diodes.

Aluminum hydroxide nanoparticles, one of the essential luminescent materials for display technology, bio-imaging, and sensors due to their non-toxicity, affordable pricing, and rare-earth-free phosphors, are synthesized via a simple method at a reaction time of 10 min at a low temperature of 200 °C. By controlling the precursor's ratio of aluminum acetylacetonate to oleic acid, UV or blue light-emitting aluminum hydroxides with oxygen defects and carbonyl radicals can be synthesized. As a result, aluminum hydroxide (Al(OH)3−x) nanoparticles overwhelmingly emit UVA light (390 nm) because of the oxygen defects in nanoparticles, and carbon-related radicals on the nanoparticles are responsible for the blue-light emission at 465 nm. Electrically driven light-emitting devices are applied using luminescent aluminum hydroxide as an emissive layer, that consists of a cost-efficient inverted bottom-emission structure as [ITO (cathode)/ZnO/emissive layers/2,2′-bis(4-(carbazol-9-yl)phenyl)-biphenyl (BCBP)/MoO3/Al (anode)]. The device with aluminum hydroxide as an emissive layer shows a maximum luminance of 215.48 cd m−2 and external quantum efficiency (EQE) of 0.12%. The new method for synthesizing UV–blue emitting aluminum hydroxides and their application to LEDs will contribute to developing the field of non-toxic optoelectronic material or UV–blue emitting devices.

Improved hydrogen generation from Al/water reaction using different synthesized Al( OH ) 3 catalyst crystalline phases

The catalytic influence of different crystalline phases of aluminum hydroxide nanoparticles for the hydrogen generation from the reaction of Al and water is described. In this study, different aluminum hydroxide powder crystalline phases (mixed-phase, bayerite phase, gibbsite phase), (Al(OH)3), were distinctly prepared using precipitation methods in different solvents (methanol, ethanol, and HNO3) at room temperature (25°C). Interestingly, the materials synthesized using ethanol and HNO3 showed bayerite. Using methanol as the solvent showed a gibbsite phase confirmed by X-ray diffraction, XPS, Raman spectroscopy, and field emission spectroscopy (FESEM). Hydrogen generation using small crystal sized bayerite phase and mixed-phase show higher catalytic efficiency than the pure and large gibbsite phase powders and the catalytic effect of different crystalline Al(OH)3 catalysts in the order of mixed phase>bayerite phase>gibbsite phase. The bayerite phase catalyst displayed the highest yield (100%) within 2 hours, but the gibbsite phase showed around 60% to 70% yield for a long time of 15 hours. However, more gibbsite phase-orientation would have strong catalytic power when it is small and plate-like thin layer (S.No.4, mixed phases). ~100% yield of hydrogen can be produced from 1 g Al/100 g water system within ~40 minutes using 1 g synthesized Al(OH)3 (S.No.4). This work delivers a novel technique to generate hydrogen for movable devices.

Rapid adsorption of Pb (II) and Cr (VI) from aqueous solution by Aluminum hydroxide nanoparticles: Equilibrium and kinetic evaluation

Pollution of water due to excessive lead and chromium levels in groundwater and wastewater has contributed to severe health issues, which has increased concern over the provision of clean water. There is a dire need for successfully eliminating these pollutants through the use of low-cost and ecosystem-friendly materials. This paper reports the synthesis of aluminum hydroxide nanoparticles of 9.9 nm as calculated through X-Ray Diffraction (XRD) analysis. Fourier-transform infrared spectroscopy (FTIR) and pH of Point Zero Charge (pHPZC) were used to establish nanomaterial and surface charge formation on the material. The effects of the various parameters, i.e., the number of nano adsorbents, contact time, initial heavy metal concentration, and pH, were examined in detail on the lead and chromium removal rate. Kinetic studies were reported to fit better with the second-order kinetics model, and experimental adsorption equilibrium data fitted well with the Freundlich isotherm model under optimized conditions. The maximum removal of 95% for Pb(II) obtained for nano adsorbent dose was: 0.5 g/L, pH: 5.5, initial lead concentration: 10 mg/L at 30 min of contact time, and maximum removal of 97% for Cr(VI) for nano adsorbent dose: 1 g/L, pH: 5, initial: 15 mg/L and 60 min of contact time.

Role of Al(OH)3 Nanocatalyst on Hydrogen Generation from Al/H2O Reaction Medium

Aluminum hydroxide nanoparticles were synthesized using sodium aluminate (NaAlO2) solution and varying amounts of ethanol and methanol under different reaction conditions. The synthesized nanoparticles were characterized using XRD, FESEM and FTIR techniques. The synthesized aluminium hydroxide nanoparticles employed as a catalyst to generate hydrogen from Al/H2O reaction medium. The maximum hydrogen generation with 100% efficiency achieved within 1.50 h at 1:1:200 ratio of Al:Al(OH)3:H2O. This mode of hydrogen generation was collective, non-hazardous, non-corrosive and very promising alternate fuel for energy system.