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This research intends to create biodegradable packaging films using solution casting method. The films are composed of guar gum, carboxymethylcellulose, and blends of these materials with citric acid as a crosslinking agent. The concentration of citric acid ranges from 10 to 30% (w w−1). This study performs a curing treatment at 140°C for 30 min on the dried films containing the crosslinking additive to promote the esterification between the polymeric matrix and the crosslinking agent. The thin films have a smooth, homogeneous, and transparent aspect. Although the crosslinking reaction – evidenced by FTIR spectra – does not affect the thickness of the material, it causes a slight color variation making the samples assume a yellowish shade. Moreover, the crosslinking process enhances the water resistance, decreases the crystallinity index, and improves the water vapor barrier and thermal resistance of the films. The SEM images reveal the excess of unreacted crosslinking agent accumulated on the samples; these particles work as a plasticizer, affecting the morphology of the films as well as their water resistance, crystallinity, and thermal resistance. [ABSTRACT FROM AUTHOR]

Micro Fibrillated Cellulose (MFC) has emerged as a promising component in film formulations due to its unique barrier prope.rties. In this study, to best of our knowledge, cardanol, a biobased plasticizer derived from cashew processing, was employed for the first time, as a dispersing aid for MFC, during a liquid assisted extrusion technique with a Poly(lactic acid) (PLA)/Poly(butylene succinate adipate) (PBSA) blend. The aim of the work is the production of PLA/PBSA/MFC films for packaging applications. The addition of different MFC amount was investigated (added at 0.5, 0.75 and 1 wt.% concentrations). The results obtained are very interesting, in fact from one hand Cardanol improved the compatibility between PLA and PBSA and avoided the MFC agglomeration. On the other hand, micro fibrillated cellulose ensured a stable film blowing and the achievement of enhanced barrier properties, seal ability and mechanical resistance. In particular, the best result was obtained with an MFC content of 0.75 wt.% for which a good compromise in terms of films ductility, barrier properties and seal ability was achieved. [ABSTRACT FROM AUTHOR]

Electrically conductive polymeric materials have recently garnered significant interest from researchers due to their potential applications in the biomedical field, including medical implants, tissue engineering, flexible electronic devices, and biosensors. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered the most successful conducting polymer due to its higher electrical conductivity and chemical stability, but it suffers from limited solubility in common organic solvents, poor mechanical properties, and low biocompatibility. An area of tremendous interest is in combining PEDOT:PSS with another polymer to form a blend or composite material in order to access the beneficial properties of both materials. However, the hydrophilic nature of PEDOT:PSS makes it difficult to produce composites with non-polar polymers. In order to overcome these problems, we have specifically designed and synthesized two new sulfonated polyurethanes (PUS) with high sulfonic acid functionality. The two polyurethanes, one water-soluble (PUS1) and one water-insoluble (PUS2), were used to make blends with two commercially available PEDOT:PSS formulations (CleviosTM FET and PH1000). Solvent cast films on glass substrates were made from water-soluble PEDOT:PSS/PUS1 blends while free-standing films of PEDOT:PSS/PUS2 blends were fabricated by compression-moulding. Ethylene glycol was used as conductivity enhancer, which showed an increase in the conductivity by several orders of magnitude in most of the compositions investigated. The highest conductivity of 438 S cm−1 was achieved for the blend with 80 wt% of PEDOT:PSS (PH1000) in PUS1. [ABSTRACT FROM AUTHOR]

This study focused on developing electrically stimulable hyaluronic acid (HA) films incorporating lipid nanoparticles (NPs) designed for the topical administration of lipophilic drugs and macromolecules. Based on beeswax and medium-chain triglycerides, NPs were successfully integrated into silk fibroin/chitosan films containing HA (NP-HA films) at a density of approximately 1011 NP/cm2, ensuring a uniform distribution. This integration resulted in a 40% increase in film roughness, a twofold decrease in Young's modulus, and enhanced film flexibility and bioadhesion work. The NP-HA films, featuring Ag/AgCl electrodes, demonstrated the capability to conduct a constant electrical current of 0.2 mA/cm2 without inducing toxicity in keratinocytes and fibroblasts during a 15-min application. Moreover, the NPs facilitated the homogeneous distribution of lipophilic drugs within the film, effectively transporting them to the skin and uniformly distributing them in the stratum corneum upon film administration. The sustained release of HA from the films, following Higuchi kinetics, did not alter the macroscopic characteristics of the film. Although anodic iontophoresis did not noticeably affect the release of HA, it did enhance its penetration into the skin. This enhancement facilitated the permeation of HA with a molecular weight (MW) of up to 2 × 105 through intercellular and transcellular routes. Confocal Raman spectroscopy provided evidence of an approximate 100% increase in the presence of HA with a MW in the range of 1.5–1.8 × 106 in the viable epidermis of human skin after only 15 min of iontophoresis applied to the films. Combining iontophoresis with NP-HA films exhibits substantial potential for noninvasive treatments focused on skin rejuvenation and wound healing. [ABSTRACT FROM AUTHOR]

Anodized aluminum oxide (AAO) molds were used for the production of large-area and inexpensive superhydrophobic polymer films. A controlled anodization methodology was developed for the fabrication of hierarchical micro–nanoporous (HMN) AAO imprint molds (HMN-AAO), where phosphoric acid was used as both an electrolyte and a widening agent. Heat generated upon repetitive high-voltage (195 V) anodization steps is effectively dissipated by establishing a cooling channel. On the HMN-AAO, within the hemispherical micropores, arrays of hexagonal nanopores are formed. The diameter and depth of the micro- and nanopores are 18/8 and 0.3/1.25 µm, respectively. The gradual removal of micropatterns during etching in both the vertical and horizontal directions is crucial for fabricating HMN-AAO with a high aspect ratio. HMN-AAO rendered polycarbonate (PC) and polymethyl methacrylate (PMMA) films with respective water contact angles (WCAs) of 153° and 151°, respectively. The increase in the WCA is 80% for PC (85°) and 89% for PMMA (80°). On the PC and PMMA films, mechanically robust arrays of nanopillars are observed within the hemispherical micropillars. The micro–nanopillars on these polymer films are mechanically robust and durable. Regular nanoporous AAO molds resulted in only a hydrophobic polymer film (WCA = 113–118°). Collectively, the phosphoric acid-based controlled anodization strategy can be effectively utilized for the manufacturing of HMN-AAO molds and roll-to-roll production of durable superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

Traditional bulk adsorbents, employed for the removal of dyes and metal ions, often face the drawback of requiring an additional filtration system to separate the filtrate from the adsorbent. In this study, we address this limitation by embedding the adsorbent into the polymer matrix through a process involving dissolution–dispersion, spin-casting, and heat-stretching. Selective dissolution and dispersion facilitate the integration of the adsorbent into the polymer matrix. Meanwhile, spin-casting ensures the formation of a uniform and thin film structure, whereas heat-induced stretching produces a porous matrix with a reduced water contact angle. The adsorbent selectively captures dye molecules, while the porous structure contributes to water permeability. We utilized inexpensive and readily available materials, such as waste polyethylene and calcium carbonate, to fabricate membranes for the removal of methylene blue dye. The effects of various parameters, such as polymer-adsorbent ratio, initial dye concentration, and annealing temperature, were investigated. Equilibrium data were fitted to Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherms. The equilibrium data were best represented by the Langmuir isotherm, with maximum adsorption capacity of 35 mg/g and 43 mg/g at 25 °C and 45 °C, respectively. The membranes can be regenerated and recycled with a 97% dye removal efficiency. The study aims to present a template for adsorbent-embedded polymeric membranes for dye removal, in which adsorbent can be tailored to enhance adsorption capacity and efficiency. [ABSTRACT FROM AUTHOR]

In this work, the production and characterization of composite films were performed using gelatin extracted after pretreatment by steam explosion at temperatures of 120 ºC (GEL120) and 130 ºC (GEL130) for 10 min, with and without the addition of Thyme Essential Oil at 0.78% (v/v), employing the casting method. The film-forming solutions were also applied as coatings for refrigerated chicken fillets, and a shelf-life analysis was conducted over 15 days. For comparison, commercial gelatin was used at all stages of production, characterization, and application. In in vitro tests, thyme essential oil exhibited antimicrobial potential against five foodborne pathogens. Due to their distinct physicochemical characteristics, the GEL130 films demonstrated higher tensile strength (7.23 MPa) and lower solubility (76.45%) compared to GEL120. The impact of thyme essential oil addition on the film properties varied depending on the type of gelatin used. The coated chicken fillets showed lower weight loss and pH; however, no significant reduction was observed for Enterobacteriaceae and aerobic mesophilic bacteria compared to the uncoated samples under refrigeration. These findings were promising for understanding the effect of incorporating thyme essential oil into films from gelatins with different characteristics. Additionally, further research is needed to enhance the application of coatings in food matrices. [ABSTRACT FROM AUTHOR]

The use of natural active substances and the development of new formulations are promising directions in the cosmetic and pharmacy industries. The primary purpose of this research was the production of microparticles based on whey protein isolate (WPI) and calcium alginate (ALG) containing Calendula officinalis flower extract and their incorporation into films composed of gelatin, WPI, and glycerol. Both swollen and dry microparticles were studied by optical microscopy and their sizes were measured. Water absorption by the microparticles, their loading capacity, and the release profile of flower extract were also characterized. The films were analyzed by mechanical tests (Young's modulus, tensile strength, elongation at break), swelling capacity, contact angle, and moisture content measurements. The presented data showed that the active ingredient was successfully enclosed in spherical microparticles and completely released after 75 min of incubation at 37 °C. The incorporation of the microparticles into polymer films caused a decrease in stiffness and tensile strength, simultaneously increasing the ductility of the samples. Moreover, the films containing microparticles displayed higher swelling ability and moisture content compared to those without them. Hence, the materials prepared in this study with Calendula officinalis flower extract encapsulated into polymeric microspheres can be a starting point for the development of new products intended for skin application; advantages include protection of the extract against external factors and a controlled release profile. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of enzymatic treatment with transglutaminase on gelatin films derived from Tambaqui skin. The gelatin was extracted through acid extraction, characterized, and subjected to enzymatic crosslinking with transglutaminase at concentrations of 1%, 2%, and 3% (w/w). The optimal conditions for film production were determined based on gelatin Bloom strength. The films were characterized according to physical, chemical, mechanical, barrier, and thermal properties. The extracted gelatin exhibited a molecular weight distribution of 52 kDa, a viscosity of 2.87 cP, and a Bloom strength of 62.71 g. The Gly–Pro–Hyd content accounted for around 31.72% of the total amino acids. The addition of 3% (w/w) transglutaminase significantly increased the gelatin Bloom strength from 62.71 to 101.6 g. However, transglutaminase crosslinking had no significant effect on film thickness and mechanical properties. On the other hand, it did lead to a significant reduction in solubility from 97.57 to 74.29% and water vapor permeability from 10.28 to 9.54 g.mm/m2.d.kPa. FTIR and TGA analyses suggest no significant alterations in the functional groups or degradation events of the gelatin films. Overall, the enzymatic treatment showed promise in reducing the solubility and water vapor permeability of Tambaqui skin gelatin films. [ABSTRACT FROM AUTHOR]

The fogging of transparent surfaces—condensation of water vapor in the air to a small liquid surface at specific environmental conditions—scatters incident light, creating a blurry vision. Fogging presents a significant challenge in various industries, adversely affecting numerous applications including plastic packaging, agricultural films, and various optical devices. Superhydrophobic or superhydrophilic coatings are the main strategies used to induce antifogging to minimize light scattering. Here, an innovative approach is introduced to mitigate fogging by modifying the surface properties of polymeric films, focusing on corona-treated polyethylene as a model. Coatings were prepared in two successive steps: the addition of radical co-polymerization of methacryloxypropyltriethoxysilane and N-vinylpyrrolidone followed by the step-growth Stöber polymerization of the formed silane monomer. The polymeric dispersion was spread on oxidized films via a Mayer rod and dried. Scanning and force microscopy, FIB, XPS, and UV-vis spectroscopy revealed a thin coating composed of cross-linked siloxane (Si-O-Si) covalently bonded to surface hydroxyls exposing pyrrolidone groups. Contact angle measurements, hot-fog examination, and durability tests indicated a durable antifogging activity. [ABSTRACT FROM AUTHOR]

The deterioration of fruits during production, transportation, and storage has become one of the main challenges in supplying fruits based on consumer requirements. Therefore, the application of suitable packaging containing effective additives to improve the properties of the used film, is very important. In this article, the studies were conducted on the use of Zeolite as an effective additive to improve the properties of polymer packaging films owing to its high porosity and low toxicity. The results showed that the presence of zeolite in a packaging film can lead to the improvement of visual observation and firmness, reduction of weight loss and total soluble solids (TSS), and increase in the pH of the packed fruits. The results obtained from reviewing the literature show that the use of zeolite has different effects on the gas permeation or adsorption through the packaging films which can control the degradative parameters of fruits and vegetables. Surface modifiers can increase the efficiency of zeolites in packaging films which are also evaluated in this article. Highlights: Packaging of fruits with the use of polymer films and zeolite as an additive increases their shelf life.Ethylene is a flammable gas with the formula C2H4 that accelerates the fruit ripening.Zeolites are hydrated aluminosilicates of alkali or alkaline earth cations that are crystalline and microporous.Zeolites are widely used in the packaging of polymeric composites, due to their chemical structure and unique characteristics.The visual features, firmness, pH, TSS, TA, and weight loss are factors to be investigated for each fruit. [ABSTRACT FROM AUTHOR]

Abstract This study aimed to develop a pyriproxyfen-based Rumino-Reticulum Device (RRD) consisting of films of poly(vinyl)alcohol (PVA) and sodium carboxymethylcellulose (NaCMC) to control the horn fly in cattle, one of the major pests of livestock. Films were obtained by the solvent casting method by PVA/NaCMC crosslinking and presented satisfactory homogeneity, drug content (104.8%) and pH (6.5), besides great absorptive capacity with swelling degree of 331.40% after 1 hour and diffusion-controlled release kinetics (Higuchi). FTIR and SEM analyzes clarify the characteristic bands of PVA, NaCMC and pyriproxyfen. The XRD and thermal analysis shows an increase in crystallinity due to pyriproxyfen (Xc:36.59%) and the active delivery alters the chain packing (Tg:74ºC). The pyriproxyfen-based RRD developed, in addition to fulfilling the characteristics of prolonged release, allows it to be rolled up (compressed form) facilitating swallowing and subsequent conversion to an expanded form that is retained in the rumen throughout the treatment period.

Electrically conductive polymeric materials have recently garnered significant interest from researchers due to their potential applications in the biomedical field, including medical implants, tissue engineering, flexible electronic devices, and biosensors. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is considered the most successful conducting polymer due to its higher electrical conductivity and chemical stability, but it suffers from limited solubility in common organic solvents, poor mechanical properties, and low biocompatibility. An area of tremendous interest is in combining PEDOT:PSS with another polymer to form a blend or composite material in order to access the beneficial properties of both materials. However, the hydrophilic nature of PEDOT:PSS makes it difficult to produce composites with non-polar polymers. In order to overcome these problems, we have specifically designed and synthesized two new sulfonated polyurethanes (PUS) with high sulfonic acid functionality. The two polyurethanes, one water-soluble (PUS1) and one water-insoluble (PUS2), were used to make blends with two commercially available PEDOT:PSS formulations (CleviosTM FET and PH1000). Solvent cast films on glass substrates were made from water-soluble PEDOT:PSS/PUS1 blends while free-standing films of PEDOT:PSS/PUS2 blends were fabricated by compression-moulding. Ethylene glycol was used as conductivity enhancer, which showed an increase in the conductivity by several orders of magnitude in most of the compositions investigated. The highest conductivity of 438 S cm−1 was achieved for the blend with 80 wt% of PEDOT:PSS (PH1000) in PUS1.

This study describes a pressure-decay method for rapid assessment of the permeability of polymeric films. The equipment is a simplified version of that proposed by ISO 15105-1 2007 without the need of both vacuum and pressure operations. The gas compressibility effect was included in the calculations to represent the actual driving force for permeation. Darcy's law was fitted to pressure loss data to yield the permeability coefficients. The equipment is inexpensive, and the equations for calculating the gas permeability coefficient are more realistic than those proposed by the standard. Validation tests were performed with commercial films using O2 and CO2. The polyethylene film had average permeability coefficients of PO2 = 1.89 × 10−17 m3⋅m⋅m−2⋅s−1⋅Pa−1 and PCO2 = 10.58 × 10−17 m3⋅m⋅m−2⋅s−1⋅Pa−1. The permeability for a commercial polyester film was PO2 = 1.54 × 10−19 m3⋅m⋅m−2⋅s−1⋅Pa−1. Values closely matched those reported in the literature. Errors ranging from 43 to 79% were observed when the gas compressibility was ignored. [ABSTRACT FROM AUTHOR]

Anodized aluminum oxide (AAO) molds were used for the production of large-area and inexpensive superhydrophobic polymer films. A controlled anodization methodology was developed for the fabrication of hierarchical micro–nanoporous (HMN) AAO imprint molds (HMN-AAO), where phosphoric acid was used as both an electrolyte and a widening agent. Heat generated upon repetitive high-voltage (195 V) anodization steps is effectively dissipated by establishing a cooling channel. On the HMN-AAO, within the hemispherical micropores, arrays of hexagonal nanopores are formed. The diameter and depth of the micro- and nanopores are 18/8 and 0.3/1.25 µm, respectively. The gradual removal of micropatterns during etching in both the vertical and horizontal directions is crucial for fabricating HMN-AAO with a high aspect ratio. HMN-AAO rendered polycarbonate (PC) and polymethyl methacrylate (PMMA) films with respective water contact angles (WCAs) of 153° and 151°, respectively. The increase in the WCA is 80% for PC (85°) and 89% for PMMA (80°). On the PC and PMMA films, mechanically robust arrays of nanopillars are observed within the hemispherical micropillars. The micro–nanopillars on these polymer films are mechanically robust and durable. Regular nanoporous AAO molds resulted in only a hydrophobic polymer film (WCA = 113–118°). Collectively, the phosphoric acid-based controlled anodization strategy can be effectively utilized for the manufacturing of HMN-AAO molds and roll-to-roll production of durable superhydrophobic surfaces.

The sensing layers for surface acoustic wave-based (SAW) sensors are the main factor in defining the selectivity and reproducibility of the responses of the sensor systems. Among the materials used as sensing layers for SAW sensors, polymers present a wide range of advantages, from availability to a large choice of chemical-sensing environments. However, depending on the physical–chemical properties of the polymer, issues about the chemical and mechanical stability of the sensing layer have been reported that can compromise the application of sensor systems in the long-term. The sensor properties are defined basically by the properties of the coating material and the quality of the coating process. The strategy used to improve the properties of polymeric coating layers for SAW technology involved the use of polyurethane (PU) in combination with a second polymer that is responsible for the sensing properties of the resulting layer; this is obtained by a reproducible and robust coating procedure. In this first part of our research, we used polymer composites of different compositions of polybutylmetacrylate (PBMA) as the sensing polymer with polyurethane. The analysis of the coating (ultrasonic parameters), the relative sensor responses and the adhesion results for the PU–PBMA composites were determined. The ultrasonic analysis and the relative sensor responses showed very reproducible and precise results, indicating the reproducibility and robustness of the coating process. Accurate correlations between the results of the ultrasonic parameters due to the coating and the relative sensor responses for the organic analytes analyzed were obtained, showing a precise quantitative relationship between the results and the constitution of the composite coating materials. The composites show practically no significant sensor responses to water. The PU–PBMA composites substantially enhanced adhesion to the surface of the piezoelectric sensor element in comparison to the coating with pure PBMA, without loss of its sensing properties. Other PU–polymer composites will be presented in the future, as well as an analysis of the selectivity for the organic analytes for these types of coating materials. [ABSTRACT FROM AUTHOR]

Wound healing is a significant healthcare problem that decreases the patient's quality of life. Hence, several agents and approaches have been widely used to help accelerate wound healing. The challenge is to search for a topical delivery system that could supply long-acting effects, accurate doses, and rapid healing activity. Topical forms of simvastatin (SMV) are beneficial in wound care. This study aimed to develop a novel topical chitosan-based platform of SMV with folic acid (FA) for wound healing. Moreover, the synergistic effect of combinations was determined in an excisional wound model in rats. The prepared SMV-FA-loaded films (SMV-FAPFs) were examined for their physicochemical characterizations and morphology. Box-Behnken Design and response surface methodology were used to evaluate the tensile strength and release characteristics of the prepared SMV-FAPFs. Additionally, Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction pattern (XRD), and animal studies were also investigated. The developed SMV-FAPFs showed a contraction of up to 80% decrease in the wound size after ten days. The results of the quantitative real-time polymerase chain reaction (RT-PCR) analysis demonstrated a significant upregulation of dermal collagen type I (CoTI) expression and downregulation of the inflammatory JAK3 expression in wounds treated with SMV-FAPFs when compared to control samples and individual drug treatments. In summary, it can be concluded that the utilization of SMV-FAPFs holds great potential for facilitating efficient and expeditious wound healing, hence presenting a feasible substitute for conventional topical administration methods. [ABSTRACT FROM AUTHOR]

Traditional bulk adsorbents, employed for the removal of dyes and metal ions, often face the drawback of requiring an additional filtration system to separate the filtrate from the adsorbent. In this study, we address this limitation by embedding the adsorbent into the polymer matrix through a process involving dissolution–dispersion, spin-casting, and heat-stretching. Selective dissolution and dispersion facilitate the integration of the adsorbent into the polymer matrix. Meanwhile, spin-casting ensures the formation of a uniform and thin film structure, whereas heat-induced stretching produces a porous matrix with a reduced water contact angle. The adsorbent selectively captures dye molecules, while the porous structure contributes to water permeability. We utilized inexpensive and readily available materials, such as waste polyethylene and calcium carbonate, to fabricate membranes for the removal of methylene blue dye. The effects of various parameters, such as polymer-adsorbent ratio, initial dye concentration, and annealing temperature, were investigated. Equilibrium data were fitted to Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherms. The equilibrium data were best represented by the Langmuir isotherm, with maximum adsorption capacity of 35 mg/g and 43 mg/g at 25 °C and 45 °C, respectively. The membranes can be regenerated and recycled with a 97% dye removal efficiency. The study aims to present a template for adsorbent-embedded polymeric membranes for dye removal, in which adsorbent can be tailored to enhance adsorption capacity and efficiency.

The use of natural active substances and the development of new formulations are promising directions in the cosmetic and pharmacy industries. The primary purpose of this research was the production of microparticles based on whey protein isolate (WPI) and calcium alginate (ALG) containing Calendula officinalis flower extract and their incorporation into films composed of gelatin, WPI, and glycerol. Both swollen and dry microparticles were studied by optical microscopy and their sizes were measured. Water absorption by the microparticles, their loading capacity, and the release profile of flower extract were also characterized. The films were analyzed by mechanical tests (Young’s modulus, tensile strength, elongation at break), swelling capacity, contact angle, and moisture content measurements. The presented data showed that the active ingredient was successfully enclosed in spherical microparticles and completely released after 75 min of incubation at 37 °C. The incorporation of the microparticles into polymer films caused a decrease in stiffness and tensile strength, simultaneously increasing the ductility of the samples. Moreover, the films containing microparticles displayed higher swelling ability and moisture content compared to those without them. Hence, the materials prepared in this study with Calendula officinalis flower extract encapsulated into polymeric microspheres can be a starting point for the development of new products intended for skin application; advantages include protection of the extract against external factors and a controlled release profile.

There is an urgent unmet medical need to develop therapeutic options for the ~50% of depression patients suffering from treatment‐resistant depression, which is difficult to treat with existing psycho‐ and pharmaco‐therapeutic options. Classical psychedelics, such as the 5HT2A agonists, have re‐emerged as a treatment paradigm for depression. Recent clinical trials highlight the potential effectiveness of 5HT2A agonists to improve mood and psychotherapeutic growth in treatment‐resistant depression patients, even in those who have failed a median of four previous medications in their lifetime. Moreover, microdosing could be a promising way to achieve long‐term alleviation of depression symptoms without a hallucinogenic experience. However, there are a gamut of practical barriers that stymie further investigation of microdosing 5HT2A agonists, including: low compliance with the complicated dosing regimen, high risk of diversion of controlled substances, and difficulty and cost administering the long‐term treatment regimens in controlled settings. Here, we developed a drug delivery system composed of multilayered cellulose acetate phthalate (CAP)/Pluronic F‐127 (P) films for the encapsulation and interval delivery of 5HT2A agonists from a fully biodegradable and biocompatible implant. CAPP film composition, thickness, and layering strategies were optimized, and we demonstrated three distinct pulses from the multilayered CAPP films in vitro. Additionally, the pharmacokinetics and biodistribution of the 5HT2A agonist 2,5‐Dimethoxy‐4‐iodoamphetamine (DOI) were quantified following the subcutaneous implantation of DOI‐loaded single and multilayered CAPP films. Our results demonstrate, for the first time, the interval delivery of psychedelics from an implantable drug delivery system and open the door to future studies into the therapeutic potential of psychedelic delivery. [ABSTRACT FROM AUTHOR]

Thin polymeric films with dielectric properties become a very important part of today’s devices, being indispensable in industry, electrical applications and not only. Nowadays polymeric materials have attracted attention in academic and industrial research due to the miniaturization at the micro and nanoscale of different electronic devices. Polymers in general are used for their light weight, good mechanical strength, dielectric properties, and optical properties, which make them multifunctional materials. This paper presents research on polymethyl methacrylate (PMMA) thin films obtained by the sol-gel method. The optimization of thin film PMMA layers has been a problem due to the importance of using the polymer in the different electronic domains. Thin films of PMMA with different thicknesses were deposited onto glass and silicon wafers in order to measure dielectric properties. For dielectric properties, the PMMA thin layer was inserted in a metal-insulator-metal structure (MIM). In order to observe the morphology and roughness of thin film, optical microscopy, scanning electron microscopy and atomic force microscopy have proceeded. The dielectric constant (k) was calculated using the electrical capacitance formula. The I-V and C-V curves showed a dielectric behavior with a leakage current between 10-11 and 10-8 A and a constant capacitance in the bias range ± 5 V.

Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments. [ABSTRACT FROM AUTHOR]

A new generation of clay-based nano pigments has been introduced, providing the advantage of both inorganic pigments and organic dyes. These nano pigments have been synthesized through a stepwise procedure where, initially, an organic dye is adsorbed onto the surface of the adsorbent, and then dye adsorbed adsorbent is used as pigment for further applications. The objective of the current paper was to examine the interaction of non-biodegradable toxic dyes, Crystal Violet (CV) and Indigo Carmine (IC), with clay minerals (montmorillonite (Mt), vermiculite (Vt), and clay bentonite (Bent)) and their organically modified forms (OMt, OBent, and OVt) and to develop a novel methodology for the synthesis of the value-added products and clay-based nano pigments without creating second generation waste materials. In our observation, the uptake of CV was more intense onto pristine Mt, Bent, and Vt, and the uptake of IC was more onto OMt, OBent, and OVt. CV was found to be in the interlayer region of Mt and Bent, as supported by XRD data. Zeta potential values confirmed the presence of CV on their surface. In contrast, in the case of Vt and organically modified forms, the dye was found on the surface, confirmed by XRD and zeta potential values. In the case of indigo carmine, the dye was found only on the surface of pristine Mt, Bent, Vt, and organo Mt, Bent, Vt. During the interaction of CV and IC with clay and organoclays, intense violet and blue-colored solid residues were obtained (also known as clay-based nano pigments). The nano pigments were used as colorants in a poly (methyl-methacrylate) (PMMA) polymer matrix to form transparent polymer films. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been touted as effective and environmentally friendly agents, which has driven their application in the biomedical field. The study compares the effectiveness of an IL agent, 1-hexyl-3-methyl imidazolium chloride ([HMIM]Cl), to current industry standards for plasticizing a methacrylate polymer. Industrial standards glycerol, dioctyl phthalate (DOP) and the combination of [HMIM]Cl with a standard plasticizer was also evaluated. Plasticized samples were evaluated for stress–strain, long-term degradation, thermophysical characterizations, and molecular vibrational changes within the structure, and molecular mechanics simulations were performed. Physico-mechanical studies showed that [HMIM]Cl was a comparatively good plasticizer than current standards reaching effectiveness at 20–30% w/w, whereas plasticizing of standards such as glycerol was still inferior to [HMIM]Cl even at concentrations up to 50% w/w. Degradation studies show HMIM-polymer combinations remained plasticized for longer than other test samples, >14 days, compared to glycerol <5 days, while remaining more pliable. The combination of [HMIM]Cl-DOP was effective at concentrations >30% w/w, demonstrating remarkable plasticizing capability and long-term stability. ILs used as singular agents or in tandem with other standards provided equivalent or better plasticizing activity than the comparative free standards. [ABSTRACT FROM AUTHOR]

Considering that microbial resistance to antibiotics is becoming an increasingly widespread problem, burn management, which usually includes the use of topical antimicrobial dressings, is still facing difficulties regarding their efficiency to ensure rapid healing. In this context, the main objective of this research is to include new oxytetracycline derivatives in polymeric-film-type dressings for the treatment of wounds caused by experimentally induced burns in rats. The structural and physico-chemical properties of synthesized oxytetracycline derivatives and the corresponding membranes were analyzed by FT-IR and MS spectroscopy, swelling ability and biodegradation capacity. In vitro antimicrobial activity using Gram-positive and Gram-negative bacterial strains and pathogenic yeasts, along with an in vivo study of a burn wound model induced in Wistar rats, was also analyzed. The newly obtained polymeric films, namely chitosan-oxytetracycline derivative membranes, showed good antimicrobial activity noticed in the tested strains, a membrane swelling ratio (MSR) of up to 1578% in acidic conditions and a biodegradation rate of up to 15.7% on day 7 of testing, which are important required characteristics for the tissue regeneration process, after the production of a burn. The in vivo study proved that chitosan-derived oxytetracycline membranes showed also improved healing effects which contributes to supporting the idea of using them for the treatment of wounds caused by burns. [ABSTRACT FROM AUTHOR]

The fogging of transparent surfaces—condensation of water vapor in the air to a small liquid surface at specific environmental conditions—scatters incident light, creating a blurry vision. Fogging presents a significant challenge in various industries, adversely affecting numerous applications including plastic packaging, agricultural films, and various optical devices. Superhydrophobic or superhydrophilic coatings are the main strategies used to induce antifogging to minimize light scattering. Here, an innovative approach is introduced to mitigate fogging by modifying the surface properties of polymeric films, focusing on corona-treated polyethylene as a model. Coatings were prepared in two successive steps: the addition of radical co-polymerization of methacryloxypropyltriethoxysilane and N-vinylpyrrolidone followed by the step-growth Stöber polymerization of the formed silane monomer. The polymeric dispersion was spread on oxidized films via a Mayer rod and dried. Scanning and force microscopy, FIB, XPS, and UV-vis spectroscopy revealed a thin coating composed of cross-linked siloxane (Si-O-Si) covalently bonded to surface hydroxyls exposing pyrrolidone groups. Contact angle measurements, hot-fog examination, and durability tests indicated a durable antifogging activity.

The present work describes the synthesis of new versatile polyurea (PU) and polyurethane (PUR) matrices, including different chain extenders, which facilitate the design of distinct, tunable properties, and high-performance derivatives. These polymers can be used for various defense and security applications, such as coatings for ballistic protection, CBRN protection, binders for energetic formulations, etc. Combining aliphatic and aromatic molecules in PU or PUR structures enables the synthesis of polymers with improved and controllable thermo-mechanical properties. Thus, for polyurea synthesis, we utilized two types of polymeric aliphatic diamines and three types of aromatic chain extenders (1,1'-biphenyl-4,4'-diamine, benzene-1,2-diamine, and 1,2-diphenylhydrazine). An analogous method was used to synthesize polyurethane films by employing one polymeric aliphatic polyol and three types of aromatic chain extenders (benzene-1,3-diol, benzene-1,4-diol, and benzene-1,2,3-triol). Subsequently, various analytic techniques (Fourier transform infrared spectroscopy–attenuated total reflectance (FTIR-ATR), single cantilever dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), frequency-dependent shear modulus survey, tensile tests, water contact angle measurements, and scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX)) have been utilized to characterize the synthesized materials and to evaluate the influence of each chain extender on their final properties. [ABSTRACT FROM AUTHOR]

This work attempts to modify the hydrophilic-adherence properties of polydimethylsiloxane (PDMS) by exposing to oxygen beam for used in painting, printing, and clothing applications. The structural and morphology changes of irradiated PDMS films are analyzed using XRD and SEM, respectively. The chemical functional group is investigated by Fourier infrared spectroscopy (FTIR). The contact angle for water is reduced from 81.38° to 42.50°, while the contact angle for diiodomethane is reduced from 63.20° to 25.40° by varying the irradiation time from 1.5 to 6 min. On the other hand, for water liquid, the adhesion work is enhanced from 82.75 to 125.5 mJ/m2, and for diiodomethane liquid, it's increased from 73.70 to 96.68 mJ/m2. Moreover, the polar energy γsp is enhanced from 6.44 to 20.25 mJ/m2, while, the γsd is increased from 26.73 to 46.01 mJ/m2, and the total γst is increased from 33.18 to 66.26 mJ/m2 by enhancing exposing time 1.5–6 min. The improvement in the adhesion and surface energy of the irradiated PDMS films is due to oxygen ion beam induced decreasing in PDMS surface hydrophobicity. The experimental data show the surface morphology, structure and surface properties of treated PDMS are modified and depend closely on the oxygen beam irradiation time. [ABSTRACT FROM AUTHOR]

Thin polymeric films with dielectric properties become a very important part of today’s devices, being indispensable in industry, electrical applications and not only. Nowadays polymeric materials have attracted attention in academic and industrial research due to the miniaturization at the micro and nanoscale of different electronic devices. Polymers in general are used for their light weight, good mechanical strength, dielectric properties, and optical properties, which make them multifunctional materials. This paper presents research on polymethyl methacrylate (PMMA) thin films obtained by the sol-gel method. The optimization of thin film PMMA layers has been a problem due to the importance of using the polymer in the different electronic domains. Thin films of PMMA with different thicknesses were deposited onto glass and silicon wafers in order to measure dielectric properties. For dielectric properties, the PMMA thin layer was inserted in a metal-insulator-metal structure (MIM). In order to observe the morphology and roughness of thin film, optical microscopy, scanning electron microscopy and atomic force microscopy have proceeded. The dielectric constant (k) was calculated using the electrical capacitance formula. The I-V and C-V curves showed a dielectric behavior with a leakage current between 10-11 and 10-8 A and a constant capacitance in the bias range ± 5 V. [ABSTRACT FROM AUTHOR]

This study introduces a novel polymer nanocomposite film of polyvinyl alcohol (PVA), carbon nitride (g-C 3 N 4), and zirconia (ZrO 2), created via solution casting for effective water remediation of organic dyes. The film shows significant potential for enhancing pollutant removal efficiency and offering a sustainable solution for water reuse. Comprehensive characterization using FTIR, XRD, UV–vis, TGA, and FESEM-EDX indicated strong interfacial interactions among PVA, ZrO 2 , and g-C 3 N 4. XPS and UV–vis spectroscopy revealed a reduction in the optical energy gap from 4.8 to 3.95 eV, enhancing photocatalytic activity. SEM confirmed uniform dispersion of ZrO 2 and g-C 3 N 4 within the PVA matrix. Kinetic studies of methylene blue (MB) degradation under solar irradiation at neutral pH showed rate constants (k) of 0.0032 min−1, 0.0094 min−1, 0.0383 min−1, and 0.0816 min−1 for PVA, PVA/(0.003)ZrO 2 /g-C 3 N 4 , PVA/(0.007)ZrO 2 /g-C 3 N 4 , and PVA/(0.01)ZrO 2 /g-C 3 N 4 , respectively. The corresponding half-life times (t 1/2) were 216.6 min, 73.7 min, 18.1 min, and 8.5 min, with photodegradation efficiencies of 10 %, 75.2 %, 90 %, and 95 %. This recyclable nanocomposite polymer, PVA/ZrO 2 /g-C 3 N 4 , shows promise for effective decontamination of organic pollutants in water, presenting an innovative approach for advanced remediation and secure wastewater recycling.This work is crucial for society as it contributes to solving the global challenge of water pollution, ensuring access to clean and safe water. • Developed a novel PVA/g-C 3 N 4 /ZrO 2 nanocomposite film for efficient water remediation. • A notable change in hydroxyl region and intensity, indicating strong interfacial interactions. • UV–vis spectroscopy demonstrated a reduced optical energy gap, influencing photocatalytic activity. • Improved degradation efficiency over 120 min of solar irradiation at pH 6.5. • Promising potential for effective degradation of organic pollutants, offering an innovative strategy for wastewater reuse. [ABSTRACT FROM AUTHOR]

MXenes polymer composites/nanocomposites have emerged as promising materials for addressing pressing challenges in water remediation and desalination owing to their exceptional properties and versatile functionalities. The incorporation of MXenes into polymer matrices enhances the mechanical properties, conductivity, and adsorption capacity of the resulting composites, enabling efficient removal of contaminants and ions from water sources. MXenes-based nanocomposites offer multifunctionality, enabling simultaneous pollutant removal, antibacterial activity, and desalination capabilities. Scalability, cost-effectiveness, and long-term stability are some challenges associated, that need to be addressed for the widespread adoption of these materials in practical water treatment systems. Current challenges and limitations associated with MXenes polymer composites, including issues related to scalability, stability, and cost-effectiveness. Strategies to mitigate these challenges via differed advance researches has been reviewed that will help the scholar and scientist of material science and environmentalist for optimizing these composite architectures, enhancing material compatibility, and adopting or exploring novel fabrication techniques. • MXenes polymer nanocomposites (M-PNCs) are advanced nanoengineered adsorbents with significant potential in water remediation and desalination applications. • The synthesis of MXenes involves various etching methods, including HF etching, electrochemical etching, alkali etching, and molten salt etching. • HF etching techniques can be further categorized into in situ HF-forming etching, acid/fluoride salt etching, bifluoride salts etching, and other in situ HF-forming systems. • M-PNCs demonstrate enhanced nanofiltration, ultrafiltration, reverse osmosis (RO), forward osmosis (FO), and ion exchange (IOX) capabilities. • The mechanisms of water desalination using M-PNCs are detailed, highlighting their efficiency and effectiveness. • The review addresses the limitations of M-PNCs and discusses future prospects for their development and application in environmental engineering. [ABSTRACT FROM AUTHOR]

Wound healing is a significant healthcare problem that decreases the patient’s quality of life. Hence, several agents and approaches have been widely used to help accelerate wound healing. The challenge is to search for a topical delivery system that could supply long-acting effects, accurate doses, and rapid healing activity. Topical forms of simvastatin (SMV) are beneficial in wound care. This study aimed to develop a novel topical chitosan-based platform of SMV with folic acid (FA) for wound healing. Moreover, the synergistic effect of combinations was determined in an excisional wound model in rats. The prepared SMV-FA-loaded films (SMV-FAPFs) were examined for their physicochemical characterizations and morphology. Box-Behnken Design and response surface methodology were used to evaluate the tensile strength and release characteristics of the prepared SMV-FAPFs. Additionally, Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction pattern (XRD), and animal studies were also investigated. The developed SMV-FAPFs showed a contraction of up to 80% decrease in the wound size after ten days. The results of the quantitative real-time polymerase chain reaction (RT-PCR) analysis demonstrated a significant upregulation of dermal collagen type I (CoTI) expression and downregulation of the inflammatory JAK3 expression in wounds treated with SMV-FAPFs when compared to control samples and individual drug treatments. In summary, it can be concluded that the utilization of SMV-FAPFs holds great potential for facilitating efficient and expeditious wound healing, hence presenting a feasible substitute for conventional topical administration methods.

The compositions and health-beneficial properties of lingonberry leaves (Vaccinium vitis-idaea L.) are well established; however, their proanthocyanidins are still heavily underutilized. Optimizing their delivery systems is key to enabling their wider applications. The present study investigates the phytochemical and 'wound-healing' properties of proanthocyanidin-rich fraction(s) (PRF) from lingonberry leaves as well as the development of optimal dermal film as a proanthocyanidin delivery system. The obtained PRF was subjected to HPLC-PDA and DMAC analyses to confirm the qualitative and quantitative profiles of different polymerization-degree proanthocyanidins. A 'wound healing' in vitro assay was performed to assess the ability of PRF to modulate the wound environment for better healing. Low concentrations of lingonberry proanthocyanidins were found to accelerate 'wound' closures, while high levels inhibited human fibroblast migration. Fifteen dermal films containing PRF were prepared and evaluated based on their polymer (MC, HEC, PEG 400) compositions, and physical, mechanical, and biopharmaceutical properties using an experimental design. The composition containing 0.30 g of MC, 0.05 g of HEC, and 3.0 g of PEG 400 was selected as a promising formulation for PRF delivery and a potentially effective functional wound dressing material, supporting the need for further investigations. [ABSTRACT FROM AUTHOR]

The ionic gelation technique using chitosan to encapsulate active compounds has received lots of attention in the literature due to its ease-of-use and known biodegradability, biocompatibility and antimicrobial properties of the polymer. In this review, main studies from the last five years involving encapsulation of active compounds (natural and commercial/synthetic) are brought together in order to understand the encapsulation mechanisms of components with chitosan as well as the physical, chemical and morphological properties of the resulting particles. The application of these nanostructures in polymeric films was then investigated, since additives for packaging are an attractive premise and have only recently started being studied in the literature. Herein, comparisons are made between free and encapsulated bioactive compounds in different film matrices, as well as the effect of this activation on structure. Finally, this work details the mechanisms involved in the production of chitosan nanoparticles with active compounds and encourages new studies to focus on their application in packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Dimethyl-organotin(IV) valsartan (Me2SnL2) and dichlorostannanediyl valsartan (SnL2Cl2) complexes were synthesized, characterized, and applied as Poly(vinyl chloride) (PVC) photo-stabilizers. The complexes were loaded within the PVC films in a weight ratio of 0.5%, and the modified films were irradiated to a UV light of 313 nm wavelength for 300 h at room temperature. The efficiency of the complexes-filled films was compared with the plain one and evaluated before and after irradiation by Fourier transform infrared spectroscopy, weight loss, gel content, change in viscosity, atomic force microscopy, and field emission scanning electron microscopy. The SnL2Cl2 complex had higher activity than the Me2SnL2 complex to retard the PVC’s photodegradation by several mechanisms.

In the agricultural sector, companies involved in the production of plastic greenhouses are currently searching for a suitable covering adapted for every climate in the world. For this purpose, this research work has determined the chemical, radiometric and mechanical properties of 53 polymeric films samples from Europe and South America. The chemical tests carried out with these samples were elemental analysis (C, H and N) and FT–IR spectrometry. The radiometric properties here studied were the transmission, absorption and reflection coefficients along the spectrum between 300 and 1100 nm. For the mechanical properties, tensile strength, tear strength and dart impact strength, tests were carried out. Finally, all these data were collected, and a multivariate statistical analysis was carried out using the SPSS statistical to group the samples into statistical groups adapted to specific climatic regions. The elemental analysis and FT–IR spectrometry allowed group the samples into nine groups. The samples were grouped according to their chemical (elemental analysis), radiometric and mechanical properties by multivariate analysis. The dendrogram separated five very different groups in terms of number of samples. These groups have specific chemical, radiometric and mechanical characteristics that separate them from the rest. These groups make it possible to narrow down the applications and correlate with the radiometric properties to see in which geographical area of the world they are most effective in increasing yields and achieving higher quality production. [ABSTRACT FROM AUTHOR]

The avocado seeds, considered as waste, were used for the extraction of oil rich in pentosans and starch. The avocado starch (AS) and a commercial starch (CS) are then used for the formation of polymeric films by casting. Avocado oil (AO, as natural crosslinker) and ethylene glycol (EG) are utilized as crosslinkers to modify the properties of the films. All polymeric structures are characterized by physical inspection, FTIR, TGA‐DSC, and water‐insoluble fraction. The results indicate that the incorporation of AO and EG augments the thermal stability by decreasing the degradation rates compared to that of the unmodified AS and CS polymeric films. In addition, the degradation temperature of the polymeric films is modified by the addition of crosslinkers. The degradation temperature of AS, AS‐AO, AS‐EG, were 300, 286, and 306°C, accordingly, whereas those for CS films are 314, 314.5, and 307.7°C for CS, CS‐AO, and CS‐EG, respectively. Our study demonstrates that natural wastes could be useful and increase the profits of the avocado processing industries. [ABSTRACT FROM AUTHOR]

A new generation of clay-based nano pigments has been introduced, providing the advantage of both inorganic pigments and organic dyes. These nano pigments have been synthesized through a stepwise procedure where, initially, an organic dye is adsorbed onto the surface of the adsorbent, and then dye adsorbed adsorbent is used as pigment for further applications. The objective of the current paper was to examine the interaction of non-biodegradable toxic dyes, Crystal Violet (CV) and Indigo Carmine (IC), with clay minerals (montmorillonite (Mt), vermiculite (Vt), and clay bentonite (Bent)) and their organically modified forms (OMt, OBent, and OVt) and to develop a novel methodology for the synthesis of the value-added products and clay-based nano pigments without creating second generation waste materials. In our observation, the uptake of CV was more intense onto pristine Mt, Bent, and Vt, and the uptake of IC was more onto OMt, OBent, and OVt. CV was found to be in the interlayer region of Mt and Bent, as supported by XRD data. Zeta potential values confirmed the presence of CV on their surface. In contrast, in the case of Vt and organically modified forms, the dye was found on the surface, confirmed by XRD and zeta potential values. In the case of indigo carmine, the dye was found only on the surface of pristine Mt, Bent, Vt, and organo Mt, Bent, Vt. During the interaction of CV and IC with clay and organoclays, intense violet and blue-colored solid residues were obtained (also known as clay-based nano pigments). The nano pigments were used as colorants in a poly (methyl-methacrylate) (PMMA) polymer matrix to form transparent polymer films.

Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments.

Organophosphorus pesticides (OPPs) were extensively used in agriculture. Due to their adverse effect, there is a need for sensitive and reliable methods to determine these agrochemicals. Microextraction techniques (ME) afford the opportunity to substantially reduce the amount of organic solvent used in classical extraction methods for pesticide analysis. Moreover, deep eutectic solvents (DES) made of components of natural origin, have been applied in microextraction techniques as a green alternative to organic solvents. The combination of thin film microextraction and DES can be seen as an alternative for thin film microextraction of OPPs from water samples. We describe a thin film microextraction-GC-MS method for the determination of OPPs from water samples. The thin film was prepared by solvent casting using cellulose triacetate (CTA) as the polymer and a deep eutectic solvent as the extracting phase. Lidocaine, menthol, dodecanoic acid, and camphor were tested as the components for DES-based film. With a film containing 70 % (w) of CTA and 30 % of the DES dodecanoic acid:lidocaine, quantitative results for the extraction of an OPPs mix were achieved. Then, the elution was performed with 2 mL of ethyl acetate. The validation of the TFME method was performed with a piece of the film suspended in 20 mL of sample solution with a contact time of 1 h. Limits of detection in the low μg L−1 range were obtained using a single quadrupole mass analyser. The thin film with pipette tip configuration was tested and preliminary results for chlorpyrifos were satisfactory. This represents the first approach to use polymeric films made of CTA and DES for TFME of OPPs, in two configuration the suspended film and pipette tip. [Display omitted] • A film with a deep eutectic solvent in cellulose triacetate matrix has been prepared. • Suspended thin film microextraction method with DES-based film evaluated. • Organophosphorus pesticides determined in different water matrices. • Pipette tip set-up useful for pesticide monitoring. [ABSTRACT FROM AUTHOR]

Vulvovaginal candidiasis (VVC) is an opportunistic infection caused by a fungus of the Candida genus, affecting approximately 75 % of women during their lifetime. Fungal resistance cases and adverse effects have been the main challenges of oral therapies. In this study, the topical application of thin films containing fluconazole (FLU) and thymol (THY) was proposed to overcome these problems. Vaginal films based only on chitosan (CH) or combining this biopolymer with pectin (PEC) or hydroxypropylmethylcellulose acetate succinate (HPMCAS) were developed by the solvent casting method. In addition to a higher swelling index, CH/HPMCAS films showed to be more plastic and flexible than systems prepared with CH/PEC or only chitosan. Biopolymers and FLU were found in an amorphous state, contributing to explaining the rapid gel formation after contact with vaginal fluid. High permeability rates of FLU were also found after its immobilization into thin films. The presence of THY in polymer films increased the distribution of FLU in vaginal tissues and resulted in improved anti- Candida activity. A significant activity against the resistant C. glabrata was achieved, reducing the required FLU dose by 50 %. These results suggest that the developed polymer films represent a promising alternative for the treatment of resistant vulvovaginal candidiasis, encouraging further studies in this context. [ABSTRACT FROM AUTHOR]

Considering that microbial resistance to antibiotics is becoming an increasingly widespread problem, burn management, which usually includes the use of topical antimicrobial dressings, is still facing difficulties regarding their efficiency to ensure rapid healing. In this context, the main objective of this research is to include new oxytetracycline derivatives in polymeric-film-type dressings for the treatment of wounds caused by experimentally induced burns in rats. The structural and physico-chemical properties of synthesized oxytetracycline derivatives and the corresponding membranes were analyzed by FT-IR and MS spectroscopy, swelling ability and biodegradation capacity. In vitro antimicrobial activity using Gram-positive and Gram-negative bacterial strains and pathogenic yeasts, along with an in vivo study of a burn wound model induced in Wistar rats, was also analyzed. The newly obtained polymeric films, namely chitosan-oxytetracycline derivative membranes, showed good antimicrobial activity noticed in the tested strains, a membrane swelling ratio (MSR) of up to 1578% in acidic conditions and a biodegradation rate of up to 15.7% on day 7 of testing, which are important required characteristics for the tissue regeneration process, after the production of a burn. The in vivo study proved that chitosan-derived oxytetracycline membranes showed also improved healing effects which contributes to supporting the idea of using them for the treatment of wounds caused by burns.

Long‐lived room temperature phosphorescence (RTP) systems have become a research focus in the field of functional materials due to their fascinating luminescence properties. However, it is still an enormous challenge to realize RTP under ambient conditions, since RTP can be quenched easily by molecular oxygen. Herein, two polymer acceptors containing triphenyl phosphonium bromide salt are designed and synthesized successfully. They are then doped into a poly(methyl methacrylate) matrix with donor molecules to form flexible films with long‐lived RTP. Interestingly, the long‐lived RTP performance is highly dependent on the grafting rate of the polymers. Upon increasing the grafting rate, the aggregation degree of polymer acceptors increases, further inhibiting the molecular movement in the aggregates and reducing nonradiative vibration deactivation of triplet excitons for achieving green long‐lived RTP. Meanwhile, the visualization of real information and complete pattern after 365 nm UV irradiation is demonstrated based on these long‐lived RTP systems, presenting application potential toward dynamic multilevel information encryption and display devices. This work provides an innovative principle for the activation of long‐lived RTP in the polymeric systems under ambient conditions. [ABSTRACT FROM AUTHOR]

Drug eluting stents (DES) can efficiently reduce the atherosclerosis and restenosis issues of coronary artery as compared to bare metal stents due to the presence of pharmaceutically active agent on their surface. Nevertheless, the arising safety concerns of DES such as delayed healing and late in stent restenosis and thrombus, has stirred the research efforts to improve the outcomes of the DES. In this connection, attention is being shifted from the use of synthetic drug to natural drug for DES. In the present work, natural compound loaded polymeric films were synthesized and their antioxidant and anticoagulation capabilities were assessed through in vitro testing. The potential of the drug loaded polymeric films to curb the production of free radicals was evaluated by carrying out antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The in vitro platelet adhesion was investigated through static platelet adhesion test while effect of synthesized films on intrinsic coagulation pathway was investigated through activated partially thromboplastin time (APTT). Moreover, to further evaluate the blood compatibility of the developed drug loaded films, in vitro hemolytic and anti-thrombolytic assays were carried out. The obtained results indicated that, incorporating herbal compounds such as ginger, magnolol and curcumin, in polymeric matrix (PVA) has significantly improved the blood compatibility of the polymeric films. Hence, it can be concluded that the synthesized drug loaded polymeric films have the potential capability to be used as a potential coating material for coating biomedical implants with good anticoagulation and antioxidant property to cater the cardiovascular issues such as atherosclerosis, restenosis and thrombus formation. [ABSTRACT FROM AUTHOR]

In the present paper, the surface properties of polydimethylsiloxane (PDMS) films were modified by exposure to argon (Ar) ion beam with a fluence of 0.25 × 1018 ion.cm−2 to 1 × 1018 ion.cm−2. The pristine and irradiated PDMS films were examined through scanning electron microscopy (SEM) and contact angle (CA) measurements. The SEM of irradiated films reveals a modification in the morphology due to ion irradiation. On the other hand, the CA data showed an enhancement in the adhesion wettability due to the formation of hydrophilic functional groups. In addition, silver nanoparticles (AgNPs) were deposited on the modified PDMS substrate using ion beam-sputtering technique. Then, PDMS and Ag/PDMS films were characterized using X-ray diffraction (XRD (and UV/Vis optical spectroscopy. XRD showed a successful deposition of AgNPs on PDMS substrate, while the optical transmittance intensity is reduced for Ag/PDMS than PDMS, and the optical band gap Eg is decreased from 5.22 eV for PDMS to 5.05 eV for Ag/PDMS. The results illustrated significant modifications in PDMS due to AgNPs deposition. [ABSTRACT FROM AUTHOR]

Dimethyl-organotin(IV) valsartan (Me2SnL2) and dichlorostannanediyl valsartan (SnL2Cl2) complexes were synthesized, characterized, and applied as Poly(vinyl chloride) (PVC) photostabilizers. The complexes were loaded within the PVC films in a weight ratio of 0.5%, and the modified films were irradiated to a UV light of 313 nm wavelength for 300 h at room temperature. The efficiency of the complexes-filled films was compared with the plain one and evaluated before and after irradiation by Fourier transform infrared spectroscopy, weight loss, gel content, change in viscosity, atomic force microscopy, and field emission scanning electron microscopy. The SnL2Cl2 complex had higher activity than the Me2SnL2 complex to retard the PVC's photodegradation by several mechanisms. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been touted as effective and environmentally friendly agents, which has driven their application in the biomedical field. The study compares the effectiveness of an IL agent, 1-hexyl-3-methyl imidazolium chloride ([HMIM]Cl), to current industry standards for plasticizing a methacrylate polymer. Industrial standards glycerol, dioctyl phthalate (DOP) and the combination of [HMIM]Cl with a standard plasticizer was also evaluated. Plasticized samples were evaluated for stress–strain, long-term degradation, thermophysical characterizations, and molecular vibrational changes within the structure, and molecular mechanics simulations were performed. Physico-mechanical studies showed that [HMIM]Cl was a comparatively good plasticizer than current standards reaching effectiveness at 20–30% w/w, whereas plasticizing of standards such as glycerol was still inferior to [HMIM]Cl even at concentrations up to 50% w/w. Degradation studies show HMIM-polymer combinations remained plasticized for longer than other test samples, >14 days, compared to glycerol 30% w/w, demonstrating remarkable plasticizing capability and long-term stability. ILs used as singular agents or in tandem with other standards provided equivalent or better plasticizing activity than the comparative free standards.

The present work describes the synthesis of new versatile polyurea (PU) and polyurethane (PUR) matrices, including different chain extenders, which facilitate the design of distinct, tunable properties, and high-performance derivatives. These polymers can be used for various defense and security applications, such as coatings for ballistic protection, CBRN protection, binders for energetic formulations, etc. Combining aliphatic and aromatic molecules in PU or PUR structures enables the synthesis of polymers with improved and controllable thermo-mechanical properties. Thus, for polyurea synthesis, we utilized two types of polymeric aliphatic diamines and three types of aromatic chain extenders (1,1’-biphenyl-4,4’-diamine, benzene-1,2-diamine, and 1,2-diphenylhydrazine). An analogous method was used to synthesize polyurethane films by employing one polymeric aliphatic polyol and three types of aromatic chain extenders (benzene-1,3-diol, benzene-1,4-diol, and benzene-1,2,3-triol). Subsequently, various analytic techniques (Fourier transform infrared spectroscopy–attenuated total reflectance (FTIR-ATR), single cantilever dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), frequency-dependent shear modulus survey, tensile tests, water contact angle measurements, and scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDX)) have been utilized to characterize the synthesized materials and to evaluate the influence of each chain extender on their final properties.