Methacrylic Acid Research Articles

Hyaluronic acid methacrylate/Pluronic F127 hydrogel enhanced with spermidine-modified mesoporous polydopamine nanoparticles for efficient synergistic periodontitis treatment

Bacterial infection, reactive oxygen species (ROS) accumulation, and persistent inflammation pose significant challenges in the treatment of periodontitis. However, the current single-modal strategy makes achieving the best treatment effect difficult. Herein, we developed a double-network hydrogel composed of Pluronic F127 (PF-127) and hyaluronic acid methacrylate (HAMA) loaded with spermidine-modified mesoporous polydopamine nanoparticles (M@S NPs). The PF-127/HAMA/M@S (PH/M@S) hydrogel was injectable and exhibited thermosensitivity and photocrosslinking capabilities, which enable it to adapt to the irregular shape of periodontal pockets. In vitro, the PH/M@S displayed multiple therapeutic effects, such as photothermal antibacterial activity, a high ROS scavenging capacity, and anti-inflammatory effects, which are beneficial for the multimodal treatment of periodontitis. The underlying anti-inflammatory mechanism of this hydrogel involves suppression of the extracellular regulated protein kinase 1/2 and nuclear factor kappa-B signalling pathways. Furthermore, in lipopolysaccharide-stimulated macrophage conditioned media, the PH/M@S effectively restored the osteogenic differentiation potential. In a rat model of periodontitis, the PH/M@S effectively reduced the bacterial load, relieved local inflammation and inhibited alveolar bone resorption. Collectively, these findings highlight the versatile functions of the PH/M@S, including photothermal antibacterial activity, ROS scavenging, and anti-inflammatory effects, indicating that this hydrogel is a promising multifunctional filling material for the treatment of periodontitis.

Molecularly Imprinted Electrochemical Sensor Constructed by Ferrocene‐Functionalized Carbon Nanotubes for Rapid Recognition and Determination of Tryptophan

AbstractMolecular imprinting is an advanced technology in the fabrication of novel chemical sensors recently applied, enabling rapid responses and highly selective binding to specific molecules, thereby enabling efficient detection of material constituents. In this study, a new molecularly imprinted electrochemical sensor (MIES) utilizing ferrocene‐functionalized carbon‐nanotubes (Fc‐CNTs) was developed for the determination of tryptophan (Trp). The formation of molecularly imprinted polymer (MIP) involves polymerization in dimethyl sulfoxide (DMSO) using Trp, methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) as the template molecules, functional monomers, and cross‐linking agents, respectively. Due to the modification of MIPs, the sensor achieves high performance. The sensor demonstrates a linear range from 1 to 45 μM and from 45 to 330 μM, with the limit of detection of 0.44 μM, exceeding that of the majority of sensors reported in the literature. Furthermore, the sensor can effectively detect Trp in real samples, including human serum and amino acid oral liquid. The recovery rate of Trp in human serum samples is 94.2 % to 105.30 %, and in amino acid oral liquid is 94.3 % to 101.68 %. This study provides a promising approach for the effective detection and analysis of tryptophan constituents.

Polymerization-Induced Self-Assembly for the Synthesis of Polyisoprene-Polystyrene Block and Random Copolymers: Towards High Molecular Weight and Conversion.

In this study, reversible addition-fragmentation chain- transfer (RAFT) polymerization combined with the polymerization-induced self-assembly (PISA) technique is used to synthesize polyisoprene (PI)-based block and random copolymers with polystyrene (PS), aiming for high molecular weight and monomer conversion. The focus is to optimize the polymerization conditions to overcome the existing challenge of cross-linking and Diels-Alder reactions during the polymerization of isoprene, which typically constrain the reaction conversion and molecular weight of the final polymers. Using a poly(methacrylic acid) (PMAA) macroRAFT agent synthesized in ethanol at 80°C, random and block copolymers of PS-PI with a target molecular weight of 50000gmole-1 and a high monomer conversion of ≈80% are achieved under optimized conditions in water-emulsion at 35°C. 1H nuclear magnetic resonance (NMR) verified the successful synthesis as well as the high content of 1,4 microstructure in polyisoprene. The thermal analysis via differential scanning calorimetry indicated distinct glass transitions for the microphase-separated PI-PS block copolymer, while a single transition for PI-PS random copolymer, indicating no microphase separation. Furthermore, dynamic light scattering analysis together with transmission electron microscopy provided further insight into the self-assembled emulsion nanoparticles of the polymers indicating a particle size in the range 70 to 130nm.

Uncovering Integrated Dual-State ESIPT-Conductivity, Redox-Capacity, and Opto-Electronic Responses Toward Hg(II)/ Cr(III) of Aliphatic Fluorescent Polymers.

Excited-state intramolecular proton transfer (ESIPT)-associated dual-state emissive aliphatic dual-light emitting conducting polymers (DLECPs) having oxidation-reduction capacities are prepared polymerizing 2-acrylamido-2-methylpropane-1-sulfonic acid, methacrylic acid, and 2-methyl-3-(N-(2-methyl-1-sulfopropan-2-yl)acrylamido)propanoic acid monomers. Of as-synthesized DLECPs, nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies, fluorescent enhancements (I/I0), and computational investigation indicate intriguing photophysical features in DLECP3 (optimum composition). In DLECP3, ─CONH─, ─CON<, and ─COOH subluminophores are recognized by density-functional theory (DFT)/time-dependent-DFT calculations and experimental investigations. ESIPT-associated dual-state emission/conductivity, aggregation-enhanced emissions, selective opto-electronic responses toward Hg(II)/Cr(III) at 437/574nm, and redox properties of DLECP3 are supported by solid-state/solution spectroscopies, time-correlated single photon counting (TCSPC) measurements, dual-state excitation dependent emissions, microscopic images, electrochemical measurements, and DFT calculations. Here, preferential interaction of Hg(II)/Cr(III) with DLECP3 (amide)/DLECP3 (imidol) and reduction/oxidation of Hg(II)/Cr(III) to Hg(I)/Cr(VI) are substantiated by UV-vis, FTIR, and X-ray photoelectron spectroscopies; TCSPC measurements; NMR-titration; electrochemical studies; alongside computational calculations. The proton-electrical conductivities of DLECP3, Hg(II/I)-DLECP3, and Cr(III/VI)-DLECP3 in solids/solutions are 15.27 × 10-5/6.16 × 10-5, 19.60 × 10-5/25.52 × 10-5, and 26.69 × 10-5/27.60 × 10-5 S cm-1, respectively.

Analysis of Trace Enrofloxacin in Environmental Waters by a Surface Molecular Imprinting Technique.

Surface-imprinted polymers (ZIF-67@MIPs) supported by ZIF-67 were prepared by precipitation polymerization using enrofloxacin (ENR) as the template molecule, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. ZIF-67@MIPs were characterized by Fourier transform infrared spectrometry, X-ray diffraction, scanning electron microscopy, and particle size distribution. The adsorption performance of the polymer was studied. The adsorption equilibrium was reached within 30 min. The maximum adsorption was 9.02 μg·mg-1. The imprinting factor was 2.58. The polymer was then used as a sorbent of a solid-phase extraction column for the separation and purification of ENR in real water samples. The extraction conditions were optimized. The method was established by high-performance liquid chromatography, and the linearity was verified by UPLC-MSMS. The correlation coefficient and limits of detection and quantification were 0.9999, 0.23 ng·mL-1, and 0.76 ng·mL-1, respectively. The recoveries were in the range of 83.79-100.68%; the relative standard deviation was 4.46-7.35%. The above data indicated that the method could be used for the separation and enrichment of ENR in real samples.

Preparation and application of a new ion-imprinted polymer for nanomolar detection of mercury(II) in environmental waters

This study introduces a novel ion-imprinted polymer for the ultrasensitive detection of mercury(II) in water. The ion-imprinted polymer was synthesized via a simple bulk polymerization process using methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, morpholine-4-carbodithioic acid phenyl ester as the chelating agent, and ammonium persulfate as the initiator. The electrochemical mercury(II) sensing capability of the ion-imprinted polymer was studied via the modification of a cost-effective carbon paste electrode. A stripping voltammetric technique was utilized to quantify the analyte ions following open-circuit enrichment. Critical experimental parameters, including the nature and concentration of the eluent, solution pH, preconcentration duration, ion-imprinted polymer dosage, sample solution volume and reduction potential, were systematically studied and optimized. Under optimal conditions, the sensor exhibited a linear response in the range of 1.0 to 240.0 nM, with a low detection limit of 0.2 nM. The sensor demonstrated remarkable selectivity against potential interfering ions, including lead(II), cadmium(II), copper(II), zinc(II), manganese(II), iron(II), magnesium(II), calcium(II), sodium(I) and cobalt(II). The practical applicability of the developed method was successfully validated through the analysis of real water samples, suggesting its potential for environmental monitoring applications.

Thermoreversible Apparel Adhesives to Enable Sustainable Garment Assembly

AbstractOver 90 million tons of fabric waste are generated annually by the apparel industry and there exists an urgent need to develop innovative approaches for the recycling of garments. Reversible adhesives can both enable the automation of labor‐intensive assembly processes and facilitate fabric recycling for a circular apparel economy. Herein, an adhesive formulation based on thermoreversible Diels–Alder chemistry has been developed via the combination of a furan‐functionalized methacrylate copolymer (F) with a bismaleimide (M). To establish the fine balance between adhesion strength and reversible bonding, an extensive screening on the optimal composition and molar mass of F is conducted. Methyl, 2‐ethylhexyl, and lauryl methacrylate are used to tune the Tg of F copolymers, whereas H‐bonding monomers such as methacrylic acid and 2‐hydroxyethyl methacrylate are utilized to strengthen the adhesive and improve its interactions with cotton. Following the optimization of F composition, F molecular weight, and M crosslinker, the scaled‐up thermoreversible adhesive is studied by rheometry and successfully dispensed via an automated assembly platform. The adhered fabrics are tested for the required shear and peel strength and then separated for fabric recycling by a short heat treatment followed by a simple solvent wash to remove adhesive residues.

Studies of the Sorption-Desorption of Pesticides from Cellulose-Based Derivative Nanocomposite Hydrogels

This study analyzed the effect of cellulose derivatives, namely methylcellulose (MC) and carboxymethylcellulose (CMC), on the stability of zeolite in a polymeric solution that would synthesize a three-dimensional network of poly(methacrylic acid)-co-polyacrylamide (PMAA-co-PAAm). Additionally, it investigated the effect of pH on the release of paraquat (PQ) and difenzoquat (DFZ) herbicides. Similar to previous studies with hydrogels containing CMC, the presence of bi and trivalent salts, such as Ca+2 and Al+3, also drastically reduced their swelling degree from 6.7 g/g in NaCl (0.15 mol·L−1) to 2.1 g/g in an AlCl3 solution (0.15 mol·L−1) for the MC nanocomposite. The viscosity results may suggest that the formation of a polysaccharide-zeolite complex contributed to the zeolite stabilization. As for the adsorption results, all samples adsorbed practically the entire concentration of both herbicides in an aqueous solution. Finally, it was also observed that the valence of the salts and molecular weight of the herbicide affect the release process, where DFZ was the herbicide with the highest concentration released. Both nanostructured hydrogels with CMC and MC exhibited lower release at pH = 7.0. These results demonstrated that a more in-depth evaluation of the phenomena involved in the application of these materials in controlled-release systems could help mitigate the impact caused by pesticides.

Robust, self-lubricating and injectable dECM-loaded hydrogels based on rapid photo-crosslinking for articular cartilage regeneration

The restoration of articular cartilage poses a significant clinical challenge due to its avascular nature and the limited presence of chondrocytes. Recently, there has been a growing emphasis on developing materials that emulate the properties of cartilage to facilitate high-quality repair. Here, an injectable dECM-loaded hydrogel (HS-dECM) with potent compressive strength and self-lubricating ability was prepared by photo-crosslinking for cartilage regeneration. The HS-dECM hydrogel was formed by integrating cartilage decellularized extracellular matrix (dECM) with hyaluronic acid methacrylate (HAMA) and sulfobetaine methacrylate (SBMA). Once injected into irregular defects, a robust hydrogel was rapidly formed in situ by UV irradiation with negligible heat release. The HS-dECM hydrogel exhibited robust compressive strength (898 ± 86 kPa), excellent fatigue resistance and a low friction coefficient, and had the feasibility of minimally invasive implantation. Besides, HS-dECM hydrogel promoted chondrogenic differentiation of BMSCs in vitro and repaired articular cartilage defects in rats. Therefore, the high-performance injectable HS-dECM hydrogel represents a novel minimally invasive strategy that significantly promote the cartilage injuries repair and regeneration.

Molecularly imprinted polymer for the selective removal of direct violet 51 from wastewater: synthesis, characterization, and environmental applications

Abstract Molecularly imprinted polymers (MIPs) are a diverse class of materials designed for selective molecular recognition. These polymers are synthesized with particular binding sites that are suited to a target molecule or a collection of structurally similar molecules through the use of a process called molecular imprinting. MIPs were synthesized in this work to specifically remove direct violet 51 from occupational leachates and aqueous solutions. Methacrylic acid functioned as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker, 2,2-azobisisobutyronitrile (AIBN) as the initiator, and alcohol as a porogenic solvent. To improve the dye removal effectiveness, a number of factors were optimized, including time, pH, analyte concentrations, and MIP/NIP dosages. The findings showed that MIPs had a much greater capacity for direct violet 51 adsorption than nonimprinted polymers (NIPs), with MIP adsorption capacity reaching 42.553 mg g−1 and NIP adsorption capacity reaching 7 mg g−1. The pseudo 2nd-order model described the adsorption kinetics, and the rate constant (K 2) for MIPs was found to be 0.00251 mg g−1 min. Furthermore, a high rebinding efficiency of 94 % was observed when the selectivity of MIPs for direct violet 51 was assessed against structurally similar templates.

Preparation and Characterization of Photo-Cross-Linkable Methacrylated Silk Fibroin and Methacrylated Hyaluronic Acid Composite Hydrogels.

Composite biomaterials with excellent biocompatibility and biodegradability are crucial in tissue engineering. In this work, a composite protein and polysaccharide photo-cross-linkable hydrogel was prepared using silk fibroin methacrylate (SFMA) and hyaluronic acid methacrylate (HAMA). SFMA was obtained by the methacrylation of degummed SF with glycidyl methacrylate (GMA), while HA was methacrylated by 2-aminoethyl methacrylate hydrochloride (AEMA). We investigated the effect of the addition of 1 wt % HAMA to 5, 10, and 20 wt % SFMA, which resulted in an increase in both static and cycling mechanical strengths. All composite hydrogels gelled under UV light in <30 s, allowing for rapid stabilization and stiffness increases. The biocompatibility of the hydrogels was confirmed by direct and indirect contact methods and by evaluation against the NIH3T3 and MC3T3 cell lines with a live-dead assay by confocal imaging. The range of obtained mechanical properties from developed composite and UV-cross-linkable hydrogels sets the basis as possible future biomaterials for various biomedical applications.

Embedded Bioprinting of Tumor-Scale Pancreatic Cancer-Stroma 3D Models for Preclinical Drug Screening.

The establishment of organotypic preclinical models that accurately resemble the native tumor microenvironment at an anatomic human scale is highly desirable to level up in vitro platforms potential for screening candidate therapies. The bioengineering of anatomic-scaled three-dimensional (3D) models that emulate native tumor scale while recapitulating their cellular and matrix components remains, however, to be fully realized. In this focus, herein, we leveraged embedded 3D bioprinting for biofabricating pancreatic ductal adenocarcinoma (PDAC) in vitro models combining gelatin-methacryloyl and hyaluronic acid methacrylate extracellular matrix (ECM)-mimetic biomaterials with human pancreatic cancer cells and cancer-associated fibroblasts to generate in vitro models capable of emulating native tumor size (∼6 mm) and stromal elements. By using a viscoelastic continuous polymeric supporting bath, tumor-scale 3D models were rapidly generated (∼50 constructs/h) and easily recovered following in-bath visible light photocrosslinking. As a proof-of-concept, tissue-scale constructs displaying physiomimetic designs were biofabricated. These models also encompass the incorporation of a stromal compartment to better emulate the cellular components of the PDAC native tumor microenvironment (TME) and its stratified spatial organization. Cell-laden tumor-size constructs remained viable for up to 14 days and were responsive to Gemcitabine in a dose-dependent mode. Cancer-stroma models also exhibited increased drug resistance compared to their monotypic counterparts, highlighting the key role of stromal cells in chemotherapeutic resistance. Overall, we report for the first time the freeform biofabrication of PDAC models exhibiting anatomic scale, different structural complexities, and engineered cancer-stromal compartments, being highly valuable for preclinical screening of therapeutics.

Construction of nano-cage imprinted sites in MOFs-based membrane for precise identification and separation

Here, ribavirin (RBV) was introduced into metal organic frameworks (MOFs) in this instance to direct the in situ fabrication of appropriate nanocage structures to facilitate the targeted binding of RBV. Well-designed nano-caged RBV imprinted membranes (NCRIMs) have remarkable antifouling capabilities and can selectively separate RBV from wastewater generated by the RBV production process by constructing imprinting sites inside the molecule. Polydopamine (PDA) is rich in hydrophilic groups (hydroxyl and amino groups) that interact with water molecules via hydrogen bonding, thereby generating a hydrate layer on the membrane surface. The synthesized RBV imprinted sites were homogeneously scattered at the interface and inside of the membrane, resulting in a satisfactory selectivity. Notably, methacrylic acid and acrylamide act as functional monomers that synergistically promote the ability to selectively recognise RBV imprinting sites. It was demonstrated that NCRIMs had favourable rebinding selectivity (αRBV/ACV = 3.28, αRBV/AZT = 2.48, αRBV/LAM = 3.72) as well as partial selectivity (βRBV /LAM = 9.48, βRBV/AZT = 8.20, βRBV/ACV = 2.95), indicating the potential of NCRIMs in practical application. What is significant is that the cooperative imprinting and modification methods devised in this study offer directions for the selective isolation of valuable components from complex environments, as well as a reference towards the design of potentially highly resistant membranes.

Zinc-based Polyoxometalate Nanozyme Functionalized Hydrogels for optimizing the Hyperglycemic-Immune Microenvironment to Promote Diabetic Wound Regeneration.

In diabetic wounds, hyperglycemia-induced cytotoxicity and impaired immune microenvironment plasticity directly hinder the wound healing process. Regulation of the hyperglycemic microenvironment and remodeling of the immune microenvironment are crucial. Here, we developed a nanozymatic functionalized regenerative microenvironmental regulator (AHAMA/CS-GOx@Zn-POM) for the effective repair of diabetic wounds. This novel construct integrated an aldehyde and methacrylic anhydride-modified hyaluronic acid hydrogel (AHAMA) and chitosan nanoparticles (CS NPs) encapsulating zinc-based polymetallic oxonate nanozyme (Zn-POM) and glucose oxidase (GOx), facilitating a sustained release of release of both enzymes. The GOx catalyzed glucose to gluconic acid and (H₂O₂), thereby alleviating the effects of the hyperglycemic microenvironment on wound healing. Zn-POM exhibited catalase and superoxide dismutase activities to scavenge reactive oxygen species and H₂O₂, a by-product of glucose degradation. Additionally, Zn-POM induced M1 macrophage reprogramming to the M2 phenotype by inhibiting the MAPK/IL-17 signaling diminishing pro-inflammatory cytokines, and upregulating the expression of anti-inflammatory mediators, thus remodeling the immune microenvironment and enhancing angiogenesis and collagen regeneration within wounds. In a rat diabetic wound model, the application of AHAMA/CS-GOx@Zn-POM enhanced neovascularization and collagen deposition, accelerating the wound healing process. Therefore, the regenerative microenvironment regulator AHAMA/CS-GOx@Zn-POM can achieve the effective conversion of a pathological microenvironment to regenerative microenvironment through integrated control of the hyperglycemic-immune microenvironment, offering a novel strategy for the treatment of diabetic wounds.

Fabrication of β-cyclodextrin-based microgels for enhancing solubility of Terbinafine: An in-vitro and in-vivo toxicological evaluation

Abstract Solubility enhancement of poorly aqueous-soluble drugs, like Terbinafine (TBN), is a critical challenge in formulating effective dosage forms. This study focused on developing β-cyclodextrin (β-CD) and polyacrylamide (PAM)-based microgels to address the solubility issue of TBN, classified as a biopharmaceutics classification system class II drug. The microgels were crafted through free radical polymerization, employing methylene bisacylamide as a cross-linker and methacrylic acid as a monomer, initiated by ammonium persulfate. Comprehensive characterizations, including Fourier transform infrared, thermo-gravimetric analysis, differential scanning calorimetry, scanning electron microscopy, powder X-ray diffractometry analysis, Zeta size, and Zeta potential, were conducted. In vitro studies, such as drug release and swelling, were performed at pH 1.2. Toxicity analysis in rabbits revealed zero toxicity. These β-CD/PAM microgels successfully enhanced the solubility of TBN.

A highly stretchable and self-adhesive cellulose complex hydrogels based on PDA@Fe3+ mediated redox reaction for strain sensor

As the application of conductive hydrogels in the field of wearable smart devices is gradually deepening, a variety of hydrogel sensors with high mechanical properties, strong adhesion, fast self-healing, and excellent conductivity are emerging. However, it is still a great challenge to manufacture hydrogel sensors combining multiple properties. Herein, we leveraged the dynamic redox reaction occurring between polydopamine (PDA) and Fe3+ to induce ammonium persulfate (APS) to generate free radicals, thereby initiating the copolymerization of hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) monomers. Then, polypyrrole-encapsulated cellulose nanofibers (PPy@CNF) and carboxymethylcellulose (CMC) were incorporated as conductive reinforced nanofillers and interpenetrating network skeleton. The obtained hydrogel cross-linked through reversible metal-ligand bonds, π-π stacking and abundant hydrogen bonding demonstrated great mechanical properties (strength 240.4 kPa, strain 1175 %) and self-healing ability (88.96 %). Particularly, the gel displayed ultrahigh durability and skin adhesive ability (75 kPa after 10 cycles), surpassing previous skin adhesion hydrogels. Furthermore, through the synergistic conductive effect of PPy@CNF and Fe3+, the prepared hydrogel sensor possessed high sensitivity (GF = 1.89) with a wide sensing range (~1000 %), which could realize the human body's daily motion detection, and had a promising application in flexible wearable electronics.

3D bioprinting of fish skin-based gelatin methacryloyl (GelMA) bio-ink for use as a potential skin substitute.

Gelatin methacryloyl (GelMA), typically derived from mammalian sources, has recently emerged as an ideal bio-ink for three-dimensional (3D) bioprinting. Herein, we developed a fish skin-based GelMA bio-ink for the fabrication of a 3D GelMA skin substitute with a 3D bioprinter. Several concentrations of methacrylic acid anhydride were used to fabricate GelMA, in which their physical-mechanical properties were assessed. This fish skin-based GelMA bio-ink was loaded with human adipose tissue-derived mesenchymal stromal cells (ASCs) and human platelet lysate (HPL) and then printed to obtain 3D ASCs + HPL-loaded GelMA scaffolds. Cell viability test and a preliminary investigation of its effectiveness in promoting wound closure were evaluated in a critical-sized full thickness skin defect in a rat model. The cell viability results showed that the number of ASCs increased significantly within the 3D GelMA hydrogel scaffold, indicating its biocompatibility property. In vivo results demonstrated that ASCs + HPL-loaded GelMA scaffolds could delay wound contraction, markedly enhanced collagen deposition, and promoted the formation of new blood vessels, especially at the wound edge, compared to the untreated group. Therefore, this newly fish skin-based GelMA bio-ink developed in this study has the potential to be utilized for the printing of 3D GelMA skin substitutes.

Pharmacokinetics of pulmonary indacaterol in rat lung using molecular imprinting solid-phase extraction coupled with RP-UPLC

Indacaterol, a β2 agonist prescribed for long-term management of patients with chronic obstructive pulmonary disease and asthma. In this study the first MISPE cartridges was developed using indacaterol as a template for its selective extraction from rat lung tissues, enabling precise pharmacokinetic evaluation at the drug’s site of action. A molecular imprinting polymer was synthesized using indacaterol as a template, methacrylic acid as a functional monomer and ethylene glycol dimethacrylate as a cross-linker with a molar ratio (1: 4: 20). The polymer was characterized by a high binding capacity of 9840 ± 0.86 and high selectivity with an imprinting factor of 4.53 ± 0.12. The synthesized polymer was utilized as a sorbent in solid-phase extraction to purify and extract indacaterol from lung tissue matrix. The optimum molecularly imprinted solid-phase extraction (MISPE) conditions were 20.0 mg of molecular imprinting polymer and non-imprinting polymer, acetonitrile as the loading solvent, acetonitrile: water (20: 80; by volume) as the washing solvent, and methanol: acetic acid (90: 10; by volume) as the eluting solvent. A pharmacokinetic study was performed for indacaterol in rat lungs using the synthesized and optimized MISPE cartridge as a tool for sample purification. These parameters were determined in the lung tissues of rats emphasizing the local exposure of indacaterol to its target organ. The Cmax and Tmax were 51.020 ± 2.810 µg mL− 1 and 0.083 ± 0.001 h, respectively. The AUC 0−24 and AUC0 − inf were 175.920 ± 1.053 and 542.000 ± 5.245 µg h mL− 1, respectively. The elimination rate constant was 0.014 ± 0.00012 h− 1 and the half-life time was 48.510 ± 0.012 h. This study successfully developed and optimized MISPE cartridges using indacaterol as a template, enabling precise pharmacokinetic evaluation in rat lung tissues. The cartridges demonstrated high binding capacity and selectivity, providing crucial insights into the local exposure of indacaterol at its site of action.

Microwave‐assisted Synthesis of Poly(methacrylic acid) Particles for Blood Purification

Microwave‐assisted Synthesis of Poly(methacrylic acid) Particles for Blood Purification

Spectroscopic and Thermal Characterisation of Interpenetrating Hydrogel Networks (IHNs) Based on Polymethacrylates and Pluronics, and Their Physicochemical Stability under Aqueous Conditions

This study describes the physicochemical characterisation of interpenetrating hydrogel networks (IHNs) composed of either poly(hydroxyethylmethacrylate, p(HEMA)) or poly(methacrylic acid, p(MAA)), and Pluronic block copolymers (grades F127, P123 and L121). IHNs were prepared by mixing the acrylate monomer with Pluronic block copolymers followed by free radical polymerisation. p(HEMA)–Pluronic blends were immiscible, evident from a lack of interaction between the two components (Raman spectroscopy) and the presence of the glass transitions (differential scanning calorimetry, DSC) of the two components. Conversely, IHNs of p(MAA) and each Pluronic were miscible, displaying a single glass transition and secondary bonding between the carbonyl group of p(MAA) and the ether groups in the Pluronic block copolymers (Raman and ATR-FTIR spectroscopy). The effect of storage of the IHNs in Tris buffer on the physical state of each Pluronic and on the loss of Pluronic from the IHNs were studied using DSC and gravimetric analysis, respectively. Pluronic loss from the IHNs was dependent on the grade of Pluronic, time of immersion in Tris buffer, and the nature of the IHN (p(HEMA) or p(MAA)). At equilibrium, the loss was greater from p(HEMA) than from p(MAA) IHNs, whereas increasing ratio of poly(propylene oxide) to poly(ethylene oxide) decreased Pluronic loss. The retention of each Pluronic grade was shown to be primarily due to its micellization; however, hydrogen bonding between Pluronic and p(MAA) (but not p(HEMA)) IHNs contributed to their retention.