Nacre-Inspired Aramid Nanofibers/Basalt Fibers Composite Paper with Excellent Flame Retardance and Thermal Stability by Constructing an Organic-Inorganic Fiber Alternating Layered Structure.

The flame-retardant paper has gradually evolved into a necessary material in various industries as a result of the rising importance of fire safety, energy efficiency, and environmental preservation. Traditional cellulose paper requires the addition of a large amount of flame retardants to achieve flame retardancy, which poses a serious threat to mechanical quality and the environment. Therefore, there is an urgent need to develop inorganic fiber flame-retardant paper with good flexibility, high thermal stability, and inherent flame retardancy. Herein, inspired by the "brick-and-mortar" layered structure of nature nacre, we developed a layered composite paper with a unique alternating arrangement of organic-inorganic fibers by synergistically integrating environmentally sustainable basalt fiber (BF) and high-performance aramid nanofibers (ANFs) through a vacuum-assisted filtration process. The as-prepared ANFs/BF composite paper exhibited low thermal conductivity (0.024 W m-1 K-1), high tensile strength (54.22 MPa), and excellent flexibility. Thanks to its excellent thermal stability, the mechanical strength remains at a high level (92%) after heat treatment at 300 °C for 60 min. Furthermore, the peak heat release rate and smoke generation of ANFs/BF composite paper decreased by 44.6 and 95.3%, respectively. Therefore, the composite paper is promising for applications as a protective layer in flexible electronic devices, cables, and fire-retardant and high-temperature fields.

Double Modification of Poly(urethane-urea): Toward Healable, Tear-Resistant, and Mechanically Robust Elastomers for Strain Sensors.

Polyurethane elastomers with mechanical robustness, tear resistance, and healing efficiency hold great potential in wearable sensors and soft robots. However, achieving excellent mechanical properties and healable capability simultaneously remains highly desirable but exclusive. Herein, we propose a straightforward procedure for double modification of poly(urethane-urea) (PUU) via thiolactone chemistry, and two different dynamic cross-linking bonds (disulfide linkages and Zn2+/imidazole coordination) are successively incorporated into the side chain of PUU, producing double cross-linking elastomers (PUU-I/Zn-S). The synergy between disulfide linkages and Zn2+/imidazole coordination forms a robust and dynamic network, endowing PUU-I/Zn-S with excellent mechanical and healing properties. The tensile stress, elongation at break, and toughness of the resultant elastomer can reach 44.06 MPa, 1000%, and 181.93 MJ m-3, respectively. Meanwhile, PUU-I/Zn-S exhibits outstanding tearing resistance with a tearing energy of 42.1 kJ m-2. The PUU-I/Zn-S can restore its mechanical robustness after self-healing at room temperature (25 ± 2 °C) or 60 °C and even maintain 91% of its original tensile strength after reprocessing two times. Additionally, PUU-I/Zn-S-based strain sensors are fabricated by introducing conductive nanofillers and demonstrate remarkable sensing capability to diverse human body motions. This work demonstrates a simple and feasible method for the postfunctionalization and enhancement of polyurethane and provides some insights into reconciling the traditional contradictory properties of mechanical robustness and healing efficiency.

A Robust, Flexible, Hydrophobic, and Multifunctional Pressure Sensor Based on an MXene/Aramid Nanofiber (ANF) Aerogel Film.

Pressure sensors with desirable flexibility, robustness, and versatility are urgently needed for complicated smart wearable devices. However, developing an ideal multifunctional flexible sensor is still challenging. In this work, a composite aerogel film sensor with an internal three-dimensional (3D) microporous and hierarchical structure is successfully fabricated by the self-assembly of aramid nanofiber (ANF) and conductive MXene by vacuum-assisted filtration and ice crystal growth. The resultant MXene/ANF aerogel film with a mass ratio of 3/7 (30% MAAF) presents high robustness with an outstanding tensile strength of 14.1 MPa and a modulus of 455 MPa while retaining appealing flexibility and sensitive characteristics due to the 3D microstructure. Accompanied by superior electric conductivity, the MAAF sensor performs noticeably in human motion and microexpression detection with a fast response time of 100 ms and a high sensitivity of 37.4 kPa-1. In addition, MAAF exhibits considerable thermal shielding performance based on the excellent thermostability. Moreover, it possesses prominent electrothermal property with a wide heating temperature range (32.7-242 °C) in a fast thermal response time (5 s) due to the Joule effect. Additionally, a hydrophobic SiO2 coating is introduced on the surface of MAAF to further broaden the sensing application, and the obtained MAAF@SiO2 sensor shows distinguished sensing capability underwater, which can be accurately applied to swimming monitoring. Therefore, this work provides a highly flexible, lightweight, robust, and multifunctional aerogel film sensor, showing promising potential in smart wearable sensing and healthcare devices, intelligent robots, and underwater detection.

Ultrafast formation of ANFs with kinetic advantage and new insight into the mechanism.

Aramid nanofibers (ANFs) have important applications in many fields, including electrical insulation and battery separators. However, a few limitations seriously restrict the application of ANFs currently, such as low preparation efficiency and the unclear preparation mechanism. To overcome these limitations, the present work proposes a new view-point from the perspective of reaction kinetics. The preparation efficiency was proven to essentially rely on the effective c(OH-). With a simple pre-treatment, a kinetic advantage was created and the preparation time of ANFs was reduced from multiple hours to 10 minutes, which was a considerable step towards practical applications. Moreover, the resultant ANF membranes still exhibited excellent properties in terms of mechanical strength (tensile strength > 160 MPa), thermal stability, light transmittance, and electrical insulation (above 90 kV mm-1). This work not only presents an ultrafast method to produce ANFs but also provides new insights into the mechanism that will benefit the subsequent development of ANF-based materials.

All-Organic Superhydrophobic Coating Comprising Raspberry-Like Particles and Fluorinated Polyurethane Prepared via Thiol-Click Reaction.

Mechanically robust superhydrophobic coatings have been extensively reported using chemically susceptible inorganic fillers like slica, titanium dioxide, and zinc oxide for constructing micro-nano structures. Organic particles are good candidates for improving chemical resistance, whereas the synthesis of organic particles with well-defined and stable micro-nano structures remains exclusive. Here, an all-organic, cross-linked superhydrophobic coating comprising raspberry-like fluorinated micro particles (RLFMP) and fluorinated polyurethane (FPU) is prepared via thiol-click reaction. Benefiting from the robust micro-nano structure of RLFMP and the excellent flexibility of FPU, the coating can maintain superhydrophobicity after severe alkali corrosion or mechanical damage, while the superhydrophobicity can be repaired readily by the fast recovery of micro-nano roughness and migration of branched fluoroalkyl chains to the coating surface. This design strategy is expected to provide a good application of thiol-click chemistry.

Preparation of Poly(thiol-urethane) Covalent Adaptable Networks Based on Multiple-Types Dynamic Motifs.

To solve the issue of polymeric materials recycling, developing intrinsic self-healing materials containing dynamic bonds has attracted many researchers' highly concerning. However, the tradeoff between their mechanical strength and stretchability always does not avoid. Herein, to surmount the above tradeoff, metal-ligand (Cu2+ -S) interactions are introduced into the cross-linking polythiourethane covalent adaptable networks (PTU CANs) with three kinds of dynamic motifs (thiourethane, disulfide, and hydrogen bonds). When the molar ratio of Cu2+ to S is 6.37%, the break strength (9.41 ± 0.34 MPa) and Young's modulus (26.02 ± 0.55 MPa) of the metal-ligand coordination complex PTU (Cu2+ -PTU-3) dramatically increase, whereas the peak strain almost does not decline (454.44 ± 3.95%). To conduct the repairing, Cu2+ -PTU-3 is further confirmed excellent repairing capability. Therefore, these new PTU CANs have significant potential for the new self-healing materials.

Recent Advances in Multidimensional (1D, 2D, and 3D) Composite Sensors Derived from MXene: Synthesis, Structure, Application, and Perspective.

With the advent of the era of intelligent manufacturing, sensors, with various detection objects, have set off a wave of enthusiasm and reached new heights in medical treatment, intelligent industry, daily life, and so on. MXene, as an emerging family of 2D transition metal carbides/nitrides, possesses impressive electrical conductivity, outstanding structural controllability, and satisfying universality with other substrates. Consequently, MXene-based sensors with various functions show a booming growth based on great research potential of MXene. To promote the orderly and efficient development of MXene application in sensors, and further accelerate market-scale application of ideal sensors, in this review, a full range research effort on current MXene-based sensors is summarized. Starting with various synthesis methods of the raw material MXene, a comprehensive summary work along with 1D, 2D, or 3D MXene-based sensors on most recent works is put forward, including the preparation method, characteristic structure, and potential sensing application of each type of MXene-based composite sensors. Ultimately, insights of the opportunities and challenges on the strength of the current reported MXene-based sensor are given.

Lightweight, Robust, Conductive Composite Fibers Based on MXene@Aramid Nanofibers as Sensors for Smart Fabrics.

Developing one-dimensional fiber-based sensors to meet the requirement of spinnability, portability, flexibility, and easeful conformability in smart wearable devices has attracted increasing interest. Here, we report highly conductive MXene@aramid nanofibers (ANFs) with a distinct skin-core structure by the wet spinning method. MXene, an emerging 2D conductive material, is applied to build internal conductive paths. ANF frameworks function as protective and skeleton structures to reduce the fiber oxidation probability and achieve superior strength. The obtained MXene@ANF fiber with superior conductivity (2515 S m-1) and tensile strength (130 MPa) works as a promising sensor for smart fabrics to detect different human movements with abundant detection motions, fast response time (100 ms), and long service life (up to 1000 cycles). Benefiting from its high flexibility, it can be sewn into textile and gloves as a smart wearable device. Besides superior thermal stability, it shows promising electrothermal properties with wide heating temperature (25-123 °C) and fast heating temperature (10 s). Therefore, the MXene@ANF fiber with the skin-core structure shows great potential as a promising sensor to be applied in electric heating and smart wearable fabrics.

Dissolving and Regeneration of meta-Aramid Paper: Converting Loose Structure into Consolidated Networks with Enhanced Mechanical and Insulation Properties.

Aramid paper has been widely used in high-voltage motors and transformers due to its excellent insulation property and thermal durability. However, the smoothness and chemical inertness of aramid fibers lead to a loose structure (voids) of aramid paper, which limits its potential applications in harsh environments, such as high-frequency and high-voltage circuits. This work reports a simple and efficient method to improve the mechanical and insulation properties of meta-aramid paper via controllable dissolving and regeneration of aramid fibers. To obtain a dense and robust structure, the pristine meta-aramid paper was immersed in a dimethyl sulfoxide/potassium hydroxide (DMSO/KOH) mixture to make aramid fibers swelled and dissolved, followed by regeneration in water vapor, eventually generating densified aramid paper with fewer voids and enhanced insulation and mechanical performance. Optimum conditions resulted in aramid paper with the best comprehensive performance, and the tensile strength, Young's modulus, and electrical breakdown strength of the consolidated aramid paper were 22.85 MPa, 0.72 GPa, and 15.3 kV/mm, respectively, which were significantly higher than those of the pristine aramid paper (12.53 MPa, 0.41 GPa, and 8.36 kV/mm). Meanwhile, such treatment did not cause any chemical structure change, and thus it still retained the excellent thermal resistance (Td > 430 °C) of aramid fibers. This simple method can effectively regulate the surface porosity and the mechanical and breakdown strength of aramid paper, as well as provide a generic method for postprocessing and enhancing aramid paper.

Flexible, Robust, and Durable Aramid Fiber/CNT Composite Paper as a Multifunctional Sensor for Wearable Applications.

Flexible paper-based sensors may be applied in numerous fields, but this requires addressing their limitations related to poor thermal and water resistance, which results in low service life. Herein, we report a paper-based composite sensor composed of carboxylic carbon nanotubes (CCNTs) and poly-m-phenyleneisophthalamide (PMIA), fabricated by a facile papermaking process. The CCNT/PMIA composite sensor exhibits an ability to detect pressures generated by various human movements, attributed to the sensor's conductive network and the characteristic "mud-brick" microstructure. The sensor exhibits the capability to monitor human motions, such as bending of finger joints and elbow joints, speaking, blinking, and smiling, as well as temperature variations in the range of 30-90 °C. Such a capability to sensitively detect pressure can be realized at different applied frequencies, gradient sagittas, and multiple twists with a short response time (104 ms) even after being soaked in water, acid, and alkali solutions. Moreover, the sensor demonstrates excellent mechanical properties and hence can be folded up to 6000 times without failure, can bear 5 kg of load without breaking, and can be cycled 2000 times without energy loss, providing a great possibility for a long sensing life. Additionally, the composite sensor shows exceptional Joule heating performance, which can reach 242 °C in less than 15 s even when powered by a low input voltage (25 V). From the perspective of industrialization, low-cost and large-scale roll-to-roll production of the paper-based sensor can be achieved, with a formed length of thousands of meters, showing great potential for future industrial applications as a wearable smart sensor for detecting pressure and temperature, with the capability of electric heating.

Highly Compressible, Thermally Stable, Light-Weight, and Robust Aramid Nanofibers/Ti3AlC2 MXene Composite Aerogel for Sensitive Pressure Sensor.

Various wearable aerogel sensors are emerging for their light weight, fairly wide sensing range, and sensitive sensing ability. Aramid nanofibers (ANFs) as a kind of burgeoning building blocks realize multifunctional applications in diversified fields for their innate extinguished mechanical property and thermal stability. Limited by their high insulating property, in this work ANFs were designed to integrate with a 2D emerging MXene sheet with a distinct conductive property. Herein, we report an MXene/ANFs composite aerogel through a feasible controllable vacuum filtration followed by a freeze-drying process. Benefiting from the inerratic 3D hierarchical and "mortar-brick" porous structure with an ultralow density of 25 mg/cm3, MXene/ANFs aerogels are proved to possess high compressible resilience and appealing sensing performance up to 1000 times. Importantly, verified by a series of simulation experiments, the MXene/ANFs aerogel sensor shows a wide detection range (2.0-80.0% compression strain), sensitive sensing property (128 kPa-1), and ultralow detection limit (100 Pa), which still play a flexible role in detecting human light movement and even vigorous sports after undergoing ultrahigh devastating pressures (∼623 kPa). In addition, the MXene/ANFs aerogel sensor can withstand a harsh high temperature of 200 °C and shows excellent flame resistance. The MXene/ANFs aerogel with excellent integrated property, especially the highly sensitive sensing property and excellent thermal stability, presents great potential for a human behavior monitoring sensor and sensing under certain extreme conditions.

Synthesis of poly(amide-thioether) with tunable hydrophilicity via thiolactone chemistry and its application in oil-in-oil emulsions.

Oil-in-oil emulsions are ideal systems for water-sensitive reactions such as polymerizations and catalytic reactions, which has received extensive attention in recent years. The application of oil-in-oil emulsions has been developed slowly due to the limited types of surfactants and complicated synthesis process. Herein, we proposed a simple method to prepare poly(amide-thioether)-based surfactant for oil-in-oil emulsions via taking advantage of single-pot multicomponent and click characters of thiolactone chemistry. Using a combination of alkyl amine and acrylamide thiolactone, the aminolysis of thiolctone occurred first, generating thiol group in-situ, and then the generated thiol group would sequentially react with the double bonds of acrylamide to form polythioether in the presence of amine. The hydrophobicity of the surfactant could be effectively adjusted by the chain length of the alkyl amine and thus this polymer could serve as a promising surfactant for oil-in-oil emulsion. Notably, the emulsion types could be switched by changing the chain length of the alkyl amine. In addition, the effects of surfactant loading, volume ratio of oil phases, oil types on the size and stability of oil-in-oil emulsions were further investigated. It was demonstrated that the oil-in-oil emulsion stabilized by poly(amide-thioether)s kept stable after more than five months. Besides, we preliminarily explored the application of the oil-in-oil emulsion to prepare closed cell foam and porous particles via photo-initiated thiol-ene polymerization. It is believed that this super-stable oil-in-oil emulsion could offer more possibilities for highly potential water-sensitive systems.

A Three-Armed Polymer with Tunable Self-Assembly and Self-Healing Properties Based on Benzene-1,3,5-tricarboxamide and Metal-Ligand Interactions.

The dynamic nature of supramolecules makes them useful in the fields of smart devices. The combination of multiple dynamic interactions in one material may bring some enhanced properties in mechanical property, self-healing property, or recyclability. Thus, it is significantly meaningful to design new materials with multi-dynamic bonds and clarify their bonding mechanisms. Here, a novel three-armed polymer based on benzene-1,3,5-tricarboxamide (BTA) is developed and the polymer could be further complexed by metal ions to form dynamic zinc-imidazole interactions. In this system, BTA is located in the center, and the ligand-functionalized monomer is copolymerized with n-butyl acrylate to form three chains. This is the first time BTA is introduced to a self-healing system to endow the polymer with assembly and self-healing properties. The composition, chemical structure, assembly behavior, mechanical properties, and self-healing properties of the polymer are investigated. It is revealed that the assembly behavior of the polymer depends on the BTA contents and time. The mechanical property can be easily tuned by ligand/metal ratio and is significantly adjusted by the polymer chain length and environment humidity. Long polymer chains not only contribute to good mechanical property but also promote the self-healing process due to the effective physical entanglement.

Lightweight and porous cellulose-based foams with high loadings of zeolitic imidazolate frameworks-8 for adsorption applications.

The excess emission of toxic gases in atmosphere and heavy metal ions in drinking water is still a serious threat to human health. In this paper, a lightweight and porous zeolitic imidazolate frameworks-8@cellulose nanofiber@cellulose foam (ZIF-8@CNF@cellulose foam) with excellent gas adsorption and heavy metal ions removal properties was prepared using a simple in situ green growth method. The nitrogen adsorption property of ZIF-8@CNF@cellulose foam was 30 times higher than pure cellulose foam. Furthermore, the adsorption testing demonstrated that the composite foam showed high adsorption capacity for fluorescent dyes (24.6 mg g-1 for rhodamine B), heavy metal ions (35.6 mg g-1 for Cr (VI)) and organic solvents (45.2 g g-1 for DMF). Additionally, the ZIF-8/cellulose-based foam with 40 wt.% CNF exhibited an excellent mechanical performance, reaching a compressive strength value of 1.30 MPa. Herein, this work provides a feasible method to prepare ZIF-8@CNF@cellulose foam composite materials, which could adsorb gas molecules and heavy metal ions and show a great potential in atmosphere and water treatment.

Comparative study of aramid nanofiber (ANF) and cellulose nanofiber (CNF).

Cellulose nanofiber (CNF) has faced challenges toward advanced applications due to the poor water resistance, wet strength, and poor thermal stability. The fabrication methods, morphologies and dispersibility between CNF and aramid nanofiber (ANF) were compared. Then the mechanical strength, especially the retention of wet strength (RWS), optical property, UV shielding, wettability and thermal stability of CNF and ANF nanopapers were further investigated. The results show that ANF and ANF nanopaper have significant advantages in dispersibility, water resistance, wet strength, thermal stability and UV-blocking ability over the CNF and CNF nanopaper. Especially the RWS of ANF nanopaper reached ˜82.5%, which notably exceeded the CNF nanopaper of 1.1%. This work demonstrates that the ANF could be an ideal alternative to CNF for advanced nanocomposites. Transparent, flexible, ultra-strong ANF nanopaper with favorable water resistance and wet strength, as well as good UV-blocking property shows great potential in variety of advanced applications.

A promising transparent and UV-shielding composite film prepared by aramid nanofibers and nanofibrillated cellulose.

An aramid nanofibers (ANFs)-functionalized nanofibrillated cellulose (NFC) composite film is effectively fabricated by the incorporation of ANFs into nanocellulose matrix. The fabrication of the composite film imitates the traditional paper-making process after homogenous mixing. The as-prepared composite film shows excellent UV-shielding performance due to the incorporation of ANFs. Thus the effect of ANFs contents is evaluated in aspects of the surface morphology, physicochemical properties including crystallinity, chemical structure and photothermal stability of composite film. Results show that the composite film with 2 wt.% of ANFs has improved mechanical properties, surface wettability compared to pure NFC film, and presents excellent UV-shielding performance ranging up to 400 nm while still retaining its high transparency. Moreover, the composite film shows high photostability even after continuous UV irradiation (365 nm) for over 12 h. The findings in the present work indicate that the ANFs-functionalized NFC composite films are promising as UV-shielding and transparent materials.

Design of double-component metal-organic framework air filters with PM2.5 capture, gas adsorption and antibacterial capacities.

A biodegradable cellulose-based air filter (Ag-MOFs@CNF@ZIF-8) with multi-layer structure was fabricated by in situ generation of double-component metal-organic frameworks (MOFs) and reinforcement of cellulose nanofiber (CNF). It exhibits good filtration performance, gas adsorption, antibacterial activity and mechanical property. The presence of MOFs could enhance the interaction between the filter and particulate matter (PM) and significantly improve the specific surface area of the composite filter. Thus, the filtration efficiency of the composite filter could reach 94.3% for PM2.5 and the nitrogen adsorption capacity increased to 109 cm3 g-1. Furthermore, the Ag-MOFs@CNF@ZIF-8 filter exhibited excellent antibacterial activity against Escherichia coli with an inhibition zone diameter of 18.1 mm. The compressive strength of the composite filter could be up to 501 kPa, approximately 3.8 times higher than that of pure cellulose filter. Herein, this composite filter has a great application potential in PM2.5 removal, toxic gas adsorption and healthcare fields.

Synthesis and characterization of brush-like multigraft copolymers PnBA-g-PMMA by a combination of emulsion AGET ATRP and emulsion polymerization.

In this paper, poly(n-butyl acrylate)-g-poly(methyl methacrylate) multigraft copolymers were synthesized by macromonomer technique and miniemulsion copolymerization. The PMMA macromonomers were obtained by an activator generated by electron transfer atom transfer radical polymerization (AGET ATRP) in emulsion system and subsequent allylation. Then the copolymerization of different macromonomers with nBA was carried out in miniemulsion system, obtaining multigraft copolymers with high molecular weight. The latex particles and distribution of emulsion AGET ATRP and miniemulsion copolymerization were characterized using laser light scattering. The molecular weight and polydispersity indices of macromonomers and multigraft copolymers were analyzed by gel permeation chromatography, and the number-average molecular weight range is 187,600-554,800 g/mol for PnBA-g-PMMA copolymers. In addition, the structural characteristics of macromonomer and brush-like copolymers were determined by infrared spectra and (1)H nuclear magnetic resonance spectroscopy. The thermal performance of brush-like copolymers were characterized by differential scanning calorimetry and thermogravimetric analysis. Atomic force microscopy results showed that the degree of microphase separation was varying with increasing PMMA content in PnBA-g-PMMA. The dynamic rheometer analysis revealed that multigraft copolymer with PMMA content of 31.4% exhibited good elastomeric properties to function as a TPE. These multigraft copolymers show a promising low cost and environmental friendly thermoplastic elastomer.

Immunosafety evaluation of a multilayer flat-plate bioartificial liver.

INTRODUCTION: To study and evaluate the immunosafety of our newly developed multilayer flat-plate bioartificial liver (BAL) in treatment of canines with acute liver failure. METHODS: Fresh porcine hepatocytes and bone marrow mesenchymal stem cells were cocultured in new BAL. Ten canine models with acute liver failure were set up through D-galactosamine administration; 24 hours after administration, the beagles were randomly allocated to a 6-hour treatment with the BAL. The beagles were divided into 2 groups by treatment times. Group 1 beagles (n = 5) received a single BAL treatment. Group 2 beagles (n = 5) received 3 BAL treatments. The hemodynamic, hematologic response and humoral immune responses to BAL therapy were studied before and after treatments. RESULTS: All beagles remained hemodynamically and hematologically stable during BAL treatments. The levels of IgG and IgM were similar before and after treatment after a single treatment. In addition, the level of CH50 in group 1 slightly decreased after the initiation of BAL treatment, and then the level recovered to baseline quickly after treatments. Time-course changes of the levels of antibodies and CH50 after 3 treatments in group 2 were similar to group 1. Only trace levels of IgG were detected in BAL medium after treatments. CONCLUSION: The multilayer flat-plate BAL showed a great immunosafety in the treatment of canines with acute liver failure and exhibited a good prospect of its use in clinic.

The influence of membrane molecular weight cutoff on a novel bioartificial liver.

Given the xenogeneic immune reaction relevant to the molecular weight cutoff of the membrane of a bioartificial liver (BAL) system, we investigated the influence of membrane molecular weight cutoff in our BAL system in this study. Acute liver failure in beagles was induced by d-galactosamine administration. Eight beagles were divided into two groups by the membrane molecular weight cutoff of the plasma component separator. Group 1 beagles were treated with BAL containing 200 kDa retention rating membrane. Group 2 beagles were treated with BAL containing 1200 kDa retention rating membrane. Each group underwent two 6-h BAL treatments that were performed on day 1 and day 21. The hemodynamic and hematologic response, humoral immune responses, and cytotoxic immune response to BAL therapy were studied before and after treatments. All beagles remained hemodynamically and hematologically stable during BAL treatments. BAL treatment was associated with a significant decline in levels of complement; however, a longer time of level maintenance was observed in Group 2. Group 2 beagles experienced a significant increase in levels of IgG and IgM after two BAL treatments. Significant levels of canine proteins were detected in BAL medium from Group 2; only trace levels of canine proteins were detected in BAL medium from Group 1. The posttreatment viability of co-culture cells in Group 2 was lower compared with Group 1, and the viability of co-culture cells after treatments was associated with deposition of canine proteins on the cells. Xenogeneic immune response was influenced by membrane molecular weight cutoff in the BAL.