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With the aim of fabricating and characterizing an optimized drug delivery system (DDS) for an effective administration of poorly water-soluble delafloxacin (DFX) via the oral route, several formulations of delafloxacin-laden solid dispersions (SD) were prepared employing the solvent-evaporation and electrospraying techniques concomitantly. Solubility and release rate of the drug in the SD were assessed. Solid-state characterization was performed via the X-ray diffraction (PXRD) and differential scanning calorimetric (DSC) analyses, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopic (FTIR) analysis. Amongst the prepared SD, an optimized formulation consisting of DFX, HPC, and SLS at the weight ratio of (1/8/0.2) showed about 9-fold higher solubility and 13-fold faster release rate of delafloxacin as compared to delafloxacin plain drug powder (DPDP). The drug existed in the amorphous form in the spherical particles and had no covalent interaction with any of the excipients. Thus, this optimized formulation might be a useful DDS for an effective administration of DFX. [ABSTRACT FROM AUTHOR]

This study presents a novel approach to developing eco‐friendly dye‐sensitized solar cells (DSSCs) using natural and renewable materials for gel polymer electrolytes (GPEs), reducing reliance on unsustainable solvents. Water is added to polar aprotic solvents, specifically ethylene carbonate/propylene carbonate (EC/PC), across various mass fractions (0:100 to 100:0). An amphiphilic hydroxypropyl cellulose (HPC) natural polymer is employed to formulate GPEs within this water‐EC/PC cosolvent system, achieving successful gelation up to 50:50 mass fractions. Incorporating water reduced the gel strength and viscosity of the GPEs. Water acted as a plasticizer, enhancing the polymer chains mobility, and creating a more flexible and permeable structure. This increased ion diffusion coefficients and ion mobility, resulting in a maximum ionic conductivity of 18.17 mS cm−1. The highest efficiency achieved in DSSCs using these GPEs is 5.81%, with elevated short‐circuit current density and reduced recombination losses. However, some compositions experienced syneresis, affecting their stability. The GPE with a 40:60 mass fraction exhibited superior long‐term stability because it is free from syneresis, though it achieved a lower efficiency (4.83%), making it the best‐performing sample. This work demonstrates the feasibility and benefits of using gel polymer electrolytes in an aqueous system, improving DSSC efficiency and sustainability. [ABSTRACT FROM AUTHOR]

In view of a need for high-performing materials, while also minimizing contributions to plastic pollution, especially ocean micro- or nano- plastic pollution, biodegradable hydroxypropyl cellulose (HPC) and nanocellulose (CNC) liquid crystal biopolymers have attracted attention as emerging fields. Their structures, phase behaviors, and advanced characterization techniques in terms of synchrotron X-ray and neutron small angle scattering of HPC solutions and CNC suspensions have been systemically studied. Diverse left- and right-hand chiral liquid crystal HPC and CNC photonic elastomer materials are further explored. To achieve their complex structure design and mass-scale manufacturing, soft matter photonic materials via advanced manufacturing techniques are critically considered in this review. The goal is to enable their applications in intelligent coating, photonic fiber, and intelligent packaging. [ABSTRACT FROM AUTHOR]

Origanum vulgare ssp. hirtum essential oil (OEO) is a natural oil with high therapeutic potential. For some applications, however, the development of novel formulations is still needed to improve the bioavailability and stability of OEO. In this study, we describe the fabrication of an original nanocomposite hydroxypropyl cellulose (HPC) physical hydrogel, containing OEO-loaded polymeric micelles, for topical delivery. The concentration of the main active compounds of OEO—carvacol and thymol—was determined using gas chromatography (GC) analysis. OEO was first encapsulated into Pluronic F127 micelles, and then embedded into HPC gel. Micellar and gel formulations of pure polymers and OEO-containing systems were characterized by dynamic light scattering (DLS) and rheology measurements, respectively. Selected formulations were evaluated for cytotoxicity and antiproliferative activity. The hydrogel formulation of HPC with micellar OEO (8% HPC, 2% F127, 1% OEO) exhibited sustained release of the oil and selectivity towards SH-4 tumor cells (an in vitro model of melanoma). [ABSTRACT FROM AUTHOR]

In the temperature-sensitive components, such as perovskite solar cells, large-area electrical connections with high electrical conductivity are also required. To fulfill the requirements, low-temperature evaporation was realized by preparing binder-free pastes with Ag flakes and a solvent mixture, followed by sintering at 140 °C. The mixed solvent was based on viscous α-terpineol with the addition of an appropriate amount of dipropylene glycol methyl ether acetate or diethylene glycol diethyl ether to achieve an azeotrope composition, followed by the addition of a low-molecular-weight hydroxypropyl cellulose to increase the viscosity and thixotropy. During sintering at 140 °C in air for up to 30 min, the paste with 49.5 wt% α-terpineol, 49.5 wt% dipropylene glycol monomethyl ether acetate, and 1 wt% hydroxypropyl cellulose mixture exhibited an excellent electrical conductivity of 7.72 × 10−6 Ω·cm despite the implementation of low-temperature sintering. The excellent processability of the prepared Ag-based pastes at 140 °C demonstrated their potential for novel application areas. [ABSTRACT FROM AUTHOR]

In the last few years, nanobiotechnology has undergone notable expansion, presenting a many applications driven by the practical viability of diverse synthesis techniques. The synthesis of silver nanocomposite through a green and eco-friendly approach is facilitated by polymer assistance, ensuring an efficient, cost-effective, and rapid process. This study specifically centers on creating eco-friendly and biodegradable nanocomposite films using hydroxypropyl (HP) cellulose and gum kondagogu (GK) through a simple casting process. In this method, silver nanocomposite (AgNPs) are synthesized by reducing AgNO3, with the biopolymer gum kondagogu serving dual roles as both a reducing and stabilizing agent. The resulting composite and Ag nanocomposite films underwent thorough characterization using techniques such as X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy (FESEM & EDX), transmission electron microscopy, and X-ray photoelectron spectroscopy. XRD and FTIR results revealed robust interactions between AgNPs and the polysaccharide chains. TEM and SEM images demonstrated the uniformity spherical, and smooth surface of HPGKP-Ag nanocomposite films, with EDAX confirming the presence of elemental Ag in the film matrix. AFM images disclosed AgNPs dispersed on the surface of composite films. XPS data clarified that silver existed solely in metallic form, with migration occurring during film formation. Furthermore, antibacterial assessments against strains such as Pseudomonas, and Streptococcus exhibited notable growth inhibition for both strains, highlighting the significant antibacterial potential of these nanocomposite films. Graphical presentation of HPGK/Ag nanocomposite film and antimicrobial activity: [ABSTRACT FROM AUTHOR]

Circularly polarized light emitting active materials are of great interest, and the convenient tuning of the circularly polarized luminescence (CPL) remains a significant challenge. Integrating fluorescent materials into chiral photonic crystals to achieve tunable CPL is a promising approach, allowing efficient manipulation of CPL by adjusting the photonic band gap (PBG). We combined carbon quantum dots (CQDs) with hydroxypropyl cellulose (HPC), which self-assembles into a cholesteric liquid crystal (CLC). The helical structure can selectively reflect right circularly polarized (RCP) light, achieving strong circular dichroism (CD) and high CPL dissymmetry factor g lum. In addition, the chiral template is thermo-responsive. The CPL wavelength can be adjusted by regulating the PBG position through temperature adjustment, while the chirality of CPL keeps high especially in the heating process. This work enables stimuli-responsive manipulation of CPL under one template through temperature regulation, which may open up enormous possibilities for the cellulose-based material in different areas.

This study introduces draw solutions for application in forward osmosis (FO) processes, combining mono propylene glycol propyl ether (PGPE) with the cellulose derivative hydroxypropyl cellulose (HPC). A total of 16 unique single‐solute and ternary organic draw solutions were prepared and evaluated, leading to the selection of three promising solutions for further investigation. Notably, eight of the initial organic draw solutions demonstrated osmotic pressures exceeding 2.4 MPa. The dynamic viscosities of all draw solutions exhibited a significant reduction with increasing temperature. Among the investigated solutions, the 0.25HPC‐3.75PGPE demonstrated the most favorable FO performance, achieving average experimental water fluxes of 11.062 and 9.852 Lm−2 h−1 (LMH) against a 1 g/L NaCl brackish feed solution across two FO runs. Practitioner Points: Hydroxypropyl cellulose (HPC, MW ~100,000) was mixed with propylene glycol propyl ether (PGPE) as draw solutes for FO processes.Seven combinations of HPC and PGPE produced osmolalities greater than 1000 mOsm/kg.0.5HPC‐7.5PGPE ternary draw solution achieved experimental water fluxes of 11.062 and 9.852 LMH against 1 g/L NaCl brackish feed solution.Leveraging the LCSTs of these ternary organic solutions holds promise for improved separation and regeneration processes. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is an emerging treatment modality that utilizes light-sensitive compounds, known as photosensitizers, to produce reactive oxygen species (ROS) that can selectively destroy malignant or diseased tissues upon light activation. This study investigates the incorporation of two porphyrin structures, 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2.) and 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1.), into hydroxypropyl cellulose (HPC) hydrogels for potential use in topical photodynamic therapy (PDT). The structural and compositional properties of the resulting hydrogels were characterized using advanced techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), UV-Visible (UV-Vis) spectroscopy, and fluorescence spectroscopy. FTIR spectra revealed a slight shift of the main characteristic absorption bands corresponding to the porphyrins and their interactions with the HPC matrix, indicating successful incorporation and potential hydrogen bonding. XRD patterns revealed the presence of crystalline domains within the HPC matrix, indicating partial crystallization of the porphyrins dispersed within the amorphous polymer structure. TGA results indicated enhanced thermal stability of the HPC–porphyrin gels compared to 10% HPC gel, with additional weight loss stages corresponding to the thermal degradation of the porphyrins. Rheological analysis showed that the gels exhibited pseudoplastic behavior and thixotropic properties, with minimal impact on the flow properties of HPC by P2.1., but notable changes in viscosity and shear stress with P2.2. incorporation, indicating structural modifications. AFM imaging revealed a homogeneous distribution of porphyrins, and UV-Vis and fluorescence spectroscopy confirmed the retention of their photophysical properties. Pharmacotechnical evaluations showed that the hydrogels possessed suitable mechanical properties, optimal pH, high swelling ratios, and excellent spreadability, making them ideal for topical application. These findings suggest that the porphyrin-incorporated HPC hydrogels have significant potential as effective therapeutic agents for topical applications. [ABSTRACT FROM AUTHOR]

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Construction of biomimetic models for structural color evolution not only gives new photonic phenomena but also provide cues for biological morphogenesis. Here, a novel confined self‐assembly method is proposed for the generation of hydroxypropyl cellulose (HPC)‐based cholesteric liquid crystals (CLCs) microbubbles. The assembly process relies on the combination of droplet microfluidics, solvent extraction, and a volume confined environment. The as‐prepared HPC structural color microbubbles have a transparent shell, an orderly arranged cholesteric liquid crystal (CLC) middle layer, and an innermost bubble core. The size of the microbubble, shell thickness, and the color of the CLC layer can be adjusted by altering the microfluidic parameters. Intriguingly, benefited from the compartmentalization effect provided by droplet microfluidics, microbubbles with multiple cores of different color combinations are generated under precise control. The self‐assembled CLCs microbubbles have bright structural color, suspending ability, and good temperature‐sensitive characteristics, making them ideal underwater sensors. The present confined assembly approach will shed light on creating novel photonic structures and the HPC microbubble will find widespread applications in multifunctional sensing, optical display, and other related fields are believed. [ABSTRACT FROM AUTHOR]

This research presents a comprehensive study on the application of hydroxypropyl cellulose/zinc oxide nanocomposite (HPC/ZnO NC) as an effective consolidant in leather conservation. The critical focus is to prevent photooxidative degradation, a significant challenge in preserving historical leather artifacts. The nanocomposite was evaluated for its protective capabilities against environmental stressors like UV radiation and moisture, mechanical robustness, and potential to stabilize acid-damaged leather. The uniform dispersion of ZnO NPs in the HPC matrix was revealed as crucial for improving leather properties, which was confirmed through SEM imaging. The HPC/ZnO NC coating effectively prevented UV-induced microcracks, surface degradation and collagen denaturation. It also demonstrated enhanced mechanical resistance, inhibiting the reduction in leather’s maximum tolerable force and increasing the elongation index, even after aging. Additionally, it exhibited improved water-repellent properties and increased the pH of the leather, offering potential benefits for the treatment of acid-degraded leathers. Overall, the findings affirm that the application of HPC/ZnO NC significantly augments the physical and mechanical properties of leather, providing enhanced resistance to environmental degradation.

In the temperature-sensitive components, such as perovskite solar cells, large-area electrical connections with high electrical conductivity are also required. To fulfill the requirements, low-temperature evaporation was realized by preparing binder-free pastes with Ag flakes and a solvent mixture, followed by sintering at 140 °C. The mixed solvent was based on viscous α-terpineol with the addition of an appropriate amount of dipropylene glycol methyl ether acetate or diethylene glycol diethyl ether to achieve an azeotrope composition, followed by the addition of a low-molecular-weight hydroxypropyl cellulose to increase the viscosity and thixotropy. During sintering at 140 °C in air for up to 30 min, the paste with 49.5 wt% α-terpineol, 49.5 wt% dipropylene glycol monomethyl ether acetate, and 1 wt% hydroxypropyl cellulose mixture exhibited an excellent electrical conductivity of 7.72 × 10−6 Ω·cm despite the implementation of low-temperature sintering. The excellent processability of the prepared Ag-based pastes at 140 °C demonstrated their potential for novel application areas.

Origanum vulgare ssp. hirtum essential oil (OEO) is a natural oil with high therapeutic potential. For some applications, however, the development of novel formulations is still needed to improve the bioavailability and stability of OEO. In this study, we describe the fabrication of an original nanocomposite hydroxypropyl cellulose (HPC) physical hydrogel, containing OEO-loaded polymeric micelles, for topical delivery. The concentration of the main active compounds of OEO—carvacol and thymol—was determined using gas chromatography (GC) analysis. OEO was first encapsulated into Pluronic F127 micelles, and then embedded into HPC gel. Micellar and gel formulations of pure polymers and OEO-containing systems were characterized by dynamic light scattering (DLS) and rheology measurements, respectively. Selected formulations were evaluated for cytotoxicity and antiproliferative activity. The hydrogel formulation of HPC with micellar OEO (8% HPC, 2% F127, 1% OEO) exhibited sustained release of the oil and selectivity towards SH-4 tumor cells (an in vitro model of melanoma).

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety of hydroxypropyl cellulose as a technological feed additive for all animal species. In its previous opinions on the safety and efficacy of the product, the FEEDAP Panel could not conclude on proper identification and characterisation as required for a feed additive. The occurrence of potential toxic impurities could also not be assessed. Based on the new data provided, the feed additive hydroxypropyl cellulose was properly identified and characterised and was shown to meet the specifications set for the food additive. Therefore, the conclusions of the safety assessment reached in the previous opinion for hydroxypropyl cellulose meeting the food additive specifications, apply to the hydroxypropyl cellulose under assessment as a feed additive. The feed additive is considered safe for all animal species, the consumer and the environment. In the absence of data, the FEEDAP Panel is not in the position to conclude on the safety for the user. [ABSTRACT FROM AUTHOR]

In this work, we functionalized hydroxypropyl cellulose (HPC) by attaching tetraphenylethylene (TPE) via copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The obtained HPC‐TPE samples displayed water‐solubility, biocompatibility, fluorescence and thermoresponsive properties. The degree of substitution (DSTPE) of HPC‐TPE1 ~ 4 was determined to be 0.002, 0.006, 0.025, and 0.053, respectively. HPC‐TPE could self‐assemble into micelles in water with the hydrodynamic radius (Rh) ranging from 164 to 190 nm. Under different DSTPE, HPC‐TPE samples showed different lower critical solution temperature (LCST) behaviors in light transmittance, Rh and fluorescence. The critical transition temperatures in light transmittance for HPC‐TPE1 ~ 4 solutions were 55–49 °C during the heating process, and were 44–40 °C during the cooling process, respectively. Moreover, HPC‐TPE demonstrated a rapid and sensitive response to Fe3+ with ignoring interferences in the presence of other common metal ions, and could also be used to image 4T1 cells. Therefore, this work offered a general approach for the synthesis of functionalized polymers with promising applications in sensing and bioimaging. [ABSTRACT FROM AUTHOR]

This research presents a comprehensive study on the application of hydroxypropyl cellulose/zinc oxide nanocomposite (HPC/ZnO NC) as an effective consolidant in leather conservation. The critical focus is to prevent photooxidative degradation, a significant challenge in preserving historical leather artifacts. The nanocomposite was evaluated for its protective capabilities against environmental stressors like UV radiation and moisture, mechanical robustness, and potential to stabilize acid-damaged leather. The uniform dispersion of ZnO NPs in the HPC matrix was revealed as crucial for improving leather properties, which was confirmed through SEM imaging. The HPC/ZnO NC coating effectively prevented UV-induced microcracks, surface degradation and collagen denaturation. It also demonstrated enhanced mechanical resistance, inhibiting the reduction in leather's maximum tolerable force and increasing the elongation index, even after aging. Additionally, it exhibited improved water-repellent properties and increased the pH of the leather, offering potential benefits for the treatment of acid-degraded leathers. Overall, the findings affirm that the application of HPC/ZnO NC significantly augments the physical and mechanical properties of leather, providing enhanced resistance to environmental degradation. [ABSTRACT FROM AUTHOR]

Abstract Construction of biomimetic models for structural color evolution not only gives new photonic phenomena but also provide cues for biological morphogenesis. Here, a novel confined self‐assembly method is proposed for the generation of hydroxypropyl cellulose (HPC)‐based cholesteric liquid crystals (CLCs) microbubbles. The assembly process relies on the combination of droplet microfluidics, solvent extraction, and a volume confined environment. The as‐prepared HPC structural color microbubbles have a transparent shell, an orderly arranged cholesteric liquid crystal (CLC) middle layer, and an innermost bubble core. The size of the microbubble, shell thickness, and the color of the CLC layer can be adjusted by altering the microfluidic parameters. Intriguingly, benefited from the compartmentalization effect provided by droplet microfluidics, microbubbles with multiple cores of different color combinations are generated under precise control. The self‐assembled CLCs microbubbles have bright structural color, suspending ability, and good temperature‐sensitive characteristics, making them ideal underwater sensors. The present confined assembly approach will shed light on creating novel photonic structures and the HPC microbubble will find widespread applications in multifunctional sensing, optical display, and other related fields are believed.

Photodynamic therapy (PDT) is an emerging treatment modality that utilizes light-sensitive compounds, known as photosensitizers, to produce reactive oxygen species (ROS) that can selectively destroy malignant or diseased tissues upon light activation. This study investigates the incorporation of two porphyrin structures, 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2.) and 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1.), into hydroxypropyl cellulose (HPC) hydrogels for potential use in topical photodynamic therapy (PDT). The structural and compositional properties of the resulting hydrogels were characterized using advanced techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), UV-Visible (UV-Vis) spectroscopy, and fluorescence spectroscopy. FTIR spectra revealed a slight shift of the main characteristic absorption bands corresponding to the porphyrins and their interactions with the HPC matrix, indicating successful incorporation and potential hydrogen bonding. XRD patterns revealed the presence of crystalline domains within the HPC matrix, indicating partial crystallization of the porphyrins dispersed within the amorphous polymer structure. TGA results indicated enhanced thermal stability of the HPC–porphyrin gels compared to 10% HPC gel, with additional weight loss stages corresponding to the thermal degradation of the porphyrins. Rheological analysis showed that the gels exhibited pseudoplastic behavior and thixotropic properties, with minimal impact on the flow properties of HPC by P2.1., but notable changes in viscosity and shear stress with P2.2. incorporation, indicating structural modifications. AFM imaging revealed a homogeneous distribution of porphyrins, and UV-Vis and fluorescence spectroscopy confirmed the retention of their photophysical properties. Pharmacotechnical evaluations showed that the hydrogels possessed suitable mechanical properties, optimal pH, high swelling ratios, and excellent spreadability, making them ideal for topical application. These findings suggest that the porphyrin-incorporated HPC hydrogels have significant potential as effective therapeutic agents for topical applications.

Abstract Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety of hydroxypropyl cellulose as a technological feed additive for all animal species. In its previous opinions on the safety and efficacy of the product, the FEEDAP Panel could not conclude on proper identification and characterisation as required for a feed additive. The occurrence of potential toxic impurities could also not be assessed. Based on the new data provided, the feed additive hydroxypropyl cellulose was properly identified and characterised and was shown to meet the specifications set for the food additive. Therefore, the conclusions of the safety assessment reached in the previous opinion for hydroxypropyl cellulose meeting the food additive specifications, apply to the hydroxypropyl cellulose under assessment as a feed additive. The feed additive is considered safe for all animal species, the consumer and the environment. In the absence of data, the FEEDAP Panel is not in the position to conclude on the safety for the user.

As performance of ternary amorphous solid dispersions (ASDs) depends on the solid-state characteristics and polymer mixing, a comprehensive understanding of synergistic interactions between the polymers in regard of dissolution enhancement of poorly soluble drugs and subsequent supersaturation stabilization is necessary. By choosing hot-melt extrusion (HME) and vacuum compression molding (VCM) as preparation techniques, we manipulated the phase behavior of ternary efavirenz (EFV) ASDs, comprising of either hydroxypropyl cellulose (HPC)-SSL or HPC-UL in combination with Eudragit® L 100–55 (EL 100–55) (50:50 polymer ratio), leading to single-phased (HME) and heterogeneous ASDs (VCM). Due to higher kinetic solid-state solubility of EFV in HPC polymers compared to EL 100–55, we visualized higher drug distribution into HPC-rich phases of the phase-separated ternary VCM ASDs via confocal Raman microscopy. Additionally, we observed differences in the extent of phase-separation in dependence on the selected HPC grade. As HPC-UL exhibited decisive lower melt viscosity than HPC-SSL, formation of partially miscible phases between HPC-UL and EL 100–55 was facilitated. Consequently, as homogeneously mixed polymer phases were required for optimal extent of solubility improvement, the manufacturing-dependent differences in dissolution performances were smaller using HPC-UL, instead of HPC-SSL, i.e. using HPC-UL was less demanding on shear stress provided by the process.

Amorphous solid dispersion (ASD) formulations are preferred enabling formulations for poorly water soluble active pharmaceutical ingredients (API) as they reliably enhance the dissolution behavior and solubility. Balancing a high stability against unwanted transformations such as crystallization and amorphous phase separation during storage on the one hand and optimizing the dissolution behavior of the formulation (high supersaturation and maintenance for long time) on the other hand are essential during formulation development. This study assessed the potential of ternary ASDs (one API and two polymers) containing the polymers hydroxypropyl cellulose together with poly(vinylpyrrolidone-co-vinyl acetate) (PVP VA64) or hydroxypropyl cellulose acetate succinate to stabilize the amorphously embedded APIs fenofibrate and simvastatin during storage and to enhance the dissolution performance. Thermodynamic predictions using the PC-SAFT model revealed for each combination of polymers the optimal polymer ratio, maximum API load that is thermodynamically stable as well as miscibility of the two polymers. The stability predictions were validated by three months enduring stability tests, followed by a characterization of the dissolution behavior. The thermodynamically most stable ASDs were found to be the ASDs with deteriorated dissolution performance. Within the investigated polymer combinations, physical stability and dissolution performance opposed each other.

Cannabidiol (CBD) is a natural terpenophenolic compound with known pharmacological activities, but the poor solubility of CBD in water limits its widespread use in medicine and pharmacy. Polymeric (nano)carriers demonstrated high potential for enhancing the solubility and therapeutic activity of lipophilic drugs such as CBD. Here, we report the elaboration of a novel hydroxypropyl cellulose (HPC)-based in situ gelling formulation for controlled delivery of CBD. In the first stage, nanosized polymeric micelles from poly(ethylene oxide)-block-poly(α-cinnamyl-ε-caprolactone-co-ε-caprolactone) (PEO-b-P(CyCL-co-CL) diblock copolymers) were used to increase the solubility of CBD in water. Different copolymers were assessed, and the carrier with the highest encapsulation efficiency (EE) and drug loading capacity (DLC) was selected for further elaboration of nanocomposite in situ gel formulations. Next, the sol-to-gel transition behavior of HPC as a function of K2SO4 concentration in the aqueous solution was investigated by microcalorimetry and dynamic oscillatory rheology, and the optimal formulation capable of forming a physical gel under physiological conditions was determined. Finally, injectable nanocomposite hydrogels comprising cannabidiol were fabricated, and their drug release profile and cytotoxicity against human tumor cell lines were evaluated. The in situ gels exhibited prolonged drug release over 12 h, controlled by gel erosion, and the cytotoxicity of formulated cannabidiol was comparable with that of a free drug. [ABSTRACT FROM AUTHOR]

Along with the increased usage of cellulose in the manufacture of novel materials, those of its derivatives that have good solubility in water or organic solvents have become increasingly important. In this study, hydroxypropyl cellulose (HPC), a cellulosic derivative with distinct features, was utilized to investigate how two of the most-selective oxidation methods currently available in the literature act on the constituent OH groups of both the side chain and the anhydroglycosidic unit in HPC. The oxidation reactions were carried out first using TEMPO, sodium hypochlorite, and sodium bromide, then sodium periodate (NaIO4), for 5 h. A combination of these two protocols was applied. The amount of aldehyde and number of carboxylic groups introduced after oxidation was determined, while the changes in the morphological features of oxidized HPC were, additionally, assessed. Furthermore, utilizing Fourier-transform infrared spectra, X-ray diffraction, and thermogravimetric studies, the chemical structure, crystallinity, and thermal stability of the oxidized HPC samples were examined and compared. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a stable molecule that presents cholesteric liquid crystal (ChLC) behavior in aqueous systems. However, this ChLC nature has not been fully utilized. In the present study, carboxy groups were introduced to HPC as a means to modify its aqueous ChLC characteristics. 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-oxidation was performed for a HPC with degrees of substitution (DS) and molar substitution of the hydroxypropyl groups of 2.19 and 4.25, respectively. The oxidation reaction not only introduced carboxy groups to the C-6 position of the main chain, but also produced ketone groups by oxidizing the hydroxy groups at the side-chain termini. These ketone moieties could be reduced selectively under mild conditions. The degree of oxidation (DO; ≤ 0.37) and degree of ketone substitution (DSketone; ≤ 0.20) were determined by conductivity titration and NMR, respectively. The effects of substituents on the ChLC properties were determined by multiple regression analysis as well as empirical and theoretical analyses. An increase in DO decreased the twisting of the ChLC structure, while an increase in DSketone had little effect on twisting but increased the distance between polymer molecular chains and decreased the rigidity of the molecule as a whole. The interaction of the carboxy groups with the solvent water appeared to be shielded when the side-chain ends were ketonized. These findings provide information on the effects of backbone and side-chain substituents on the supramolecular structures of water-soluble ChLC as well as give the possibility of controlling ChLC via ionic functional groups. [ABSTRACT FROM AUTHOR]

For environmental friendliness. new coloring methods are required to replace dyeing of textile products. Cellulose derivatives forming a cholesteric liquid crystal (CLC) structure under a room condition were synthesized by the esterification of hydroxypropyl cellulose (HPC) with propionic anhydride. Structural colored fibers were prepared by wet spinning from the acetone solution of these cellulose derivatives to water as a coagulation bath and liquid-crystallizing by removing water in the fiber under controlled humidity. The pitch of CLC structure was decreased with increasing fiber width deformation by self-weight under controlled humidity. The reflection intensity of CLC structure was increased with increasing the high shear rate at the wet spinning. lowering the degree of esteritication, and lowing the rate to form CLC structures by controlled humidity. The fiber improved its reflection strength when it was kept under higher humidity above 80 % RH after crystallization via removing the water in the fiber. The fiber improved its pitch of CLC, when it was kept under higher humidity above 95 % RH and higher temperature bellow 50 °C after liquid crystallization via removing the water in the fiber. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a review of cholesteric liquid crystal (CLC) sensors based on water and hydroxypropyl cellulose (HPC) mixtures for healthcare and human quality of life applications. First, an overview of the sensors system demands for healthcare and environmental sensing is presented in which there is also a discussion on the sensors technologies conventionally applied in these scenarios. Then, a discussion of the water‐HPC mixtures and the formation of the CLCs as well as their operation principle and fabrication methods is presented. Thereafter, the applications of such technologies for the assessment of different parameters related to biomechanics, medical conditions, and environment contamination are discussed in detail. Thus, the use of CLC sensors based on HPC membranes provides novel sustainable approaches for highly sensitive sensors systems with intuitive signal acquisition and analysis. For these reasons, one can envisage a widespread of such technologies due to the mentioned advantages in conjunction with low cost, flexibility in fabrication, simple signal processing, biocompatibility, and biodegradability.

The phase transition temperature of hydroxypropyl cellulose (HPC), that is, the lower critical solution temperature (LCST), is reduced by hydrogen bonding with hyaluronic acid (HA). The turbidity change of the sample with temperature is investigated by using a variable temperature ultraviolet spectrophotometer (UV-Vis). The effect on the phase transition temperature of HPC is observed by changing the HA concentration, molecular weight, HPC concentration, solution pH, and the addition of monomer AA or polymer PAA. The results obtained that HPC can achieve lower LCST in the mixed solution of HA and HPC added with PAA. Moreover, HA can change the phase transition temperature of HPC under acidic, alkaline and even neutral conditions. HA has been proved to be an efficient material that can effectively reduce the phase transition temperature of HPC and change its turbidity at a lower temperature, and can be applied to smart windows to change the amount of light transmitted. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a hydroxypropylated derivative of cellulose with a lyotropic liquid crystal (LC) property and thermochromism. We introduced HPC into poly 2-acrylamido-2-methylpropane sulfonic acid (PAMPS), forming an anisotropic hydrogel by mechanical shearing. The polymerized long-range ordered HPC/PAMPS hydrogel shows a uniform interference color between crossed polarizers, which could be applied as a multifunctional sensor responding to temperature, pressure, and tensile force. In particular, the oriented HPC/PAMPS hydrogel, as a temperature sensor, can respond to a wide temperature range, and the vivid interference color change has little transmittance loss due to the confinement of a hydrogel network. This work may broaden the application areas of the anisotropic hydrogel and present inspirations into the multi-functional cellulose-based hydrogel sensors. [ABSTRACT FROM AUTHOR]

In this research, cellulose nanocrystals (CNC) were prepared with a concentration of 2% through a hydrolysis procedure using concentrated sulfuric acid (H2SO4). This was followed by the preparation of CNC/Klucel E nanocomposites films with various concentrations (10, 15, 20, 30, 50 %). The obtained films were investigated and evaluated using different techniques such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and tensile strength testing. Based on the results obtained, films with concentrations of 20 and 30 %, which gave the best results, were applied on aged wood specimens in order to study the influence of this nanocomposite on different properties of wood. The influence was studied in terms of mechanical properties, change in chemical composition, and change in physical appearance through tensile tests, Fourier Transform Infrared Spectroscopy (FT-IR) and color change measurements (CIE lab), respectively. The tensile strength of the films was improved after addition of CNC to Klucel E by almost 70% at 30% concentration, and compression strength for wooden samples significantly increased after using the same concentration of the nanocomposite, which reached 35 MPa. [ABSTRACT FROM AUTHOR]

In the present paper the cytotoxicity of series of sol-gel based copper doped SiO2/HPC composites on lung cancer cell line (A549) and primary human umbilical cord endothelial cells (HUVEC) was investigated. Hydroxypropyl cellulose (HPC), tetraethyl ortosilicate (TEOS) were used for preparation of amorphous matrix in which the copper was added as Cu(NO3)2 *3H2O or CuSO4*5H2O in concentration range of 0 - 5 wt. %. We observed that the composite materials at low concentration of Cu (0.5 wt. %) showed no toxic effects on both cell types. The composite material with CuSO4*5H2O was found relatively more toxic, and furthermore, cancer cells are more sensitive to the copper concentration increase to non-cancer cells. The concentration of Cu ions of 2.5 and 5 wt. % were toxic to both cancer and non-cancer cells at 24th hour. At 72th hour of incubation some restoration of cell viability was observed. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a functional material with numerous applications as a drug solubilizer, thickener, and stabilizer. Herein, the mobile and rigid regions of HPC are investigated using liquid‐ and solid‐state NMR, respectively, in the high‐viscosity regime of concentrated aqueous samples, below and above the formation of an ordered chiral liquid‐crystalline (LC) mesophase. Liquid NMR 13C relaxation and hydration studies reveal that hydroxypropyl pendant chains remain more fluid than the pyranose sugar rings at concentrations below the formation of the LC phase. The inner part of the pendant chains close to the cellulose backbone exhibits a higher water structuration and a lower water renewal than the outer part and the pyranoses, which likely compensates for their higher hydrophobicity. When the LC phase is formed, the sample viscosity increases and the differences in flexibility and hydration of the pendant chains are reduced with respect to the pyranoses, while the whole system is rigidified. The system is not completely rigid even at concentrations above the formation of LC, as the interaction of water with the pyranoses considerably enhances their fluidity. In contrast, the pendant chains are much less affected. [ABSTRACT FROM AUTHOR]

Today, polymer systems can be formed to respond to single stimuli or multiple stimuli by changing their properties. The use of these systems, which are designed to be sensitive to stimuli, is expanding in a wide range of applications. Herein, microspheres of sodium alginate (NaAlg) and hydroxypropyl cellulose (HPC) sensitive to dual stimuli for the controlled release of model drug paracetamol were produced by the ionotropic gelation method in the presence of Zn2+ ions. FTIR, DSC, TGA, SEM, and particle size measurements were used to describe the blend microspheres. Low critical solution temperatures (LCST) of polymer blends at different ratios were determined and the biggest change according to the LCST value of HPC was found to be approximately 1–2 °C lower than 41 °C in microspheres with a NaAlg/HPC ratio of 50/50. In vitro release experiments of paracetamol from microspheres were carried out in a gastrointestinal tract simulation environment at two different temperatures (37 °C and 47 °C). From the release profiles, paracetamol release varied depending on the NaAlg/HPC ratio, the paracetamol content in the microspheres, the exposure time to Zn2+ ions, and the pH of the medium. Among the microsphere formulations, the highest entrapment efficiency was 57.86%, obtained for B7 formulation microspheres with a NaAlg/HPC ratio of 70/30, a paracetamol loading percentage of 20%, and a crosslinking time of 5 min. Microspheres of sodium alginate (NaAlg) and hydroxypropyl cellulose (HPC) sensitive to dual stimuli for the controlled release of model drug paracetamol were produced by the ionotropic gelation method in the presence of Zn2+ ions. LCST values of the microspheres with a NaAlg/HPC ratio of 50/50 were significantly lower by 1–2 °C than the LCST value of HPC, and the release results supported the temperature sensitivity of the microspheres. Among the microsphere formulations, the highest entrapment efficiency was 57.86% obtained for B7 formulation microspheres. These microspheres can be used as a temperature-sensitive drug delivery system in the biomedical field and also as an encapsulation system of cancer drugs for cancer treatment modalities such as hyperthermia. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a widely commercialized cellulose derivative. While it is typically used as a binder or stabilizer for foods and pharmaceuticals, it can also form a cholesteric liquid crystal in aqueous solution. Moreover, at high HPC concentrations this lyotropic and thermotropic mesophase is known to reflect structural color. However, it remains a challenge to retain this vibrant coloration into the solid state. Herein, by combining the emulsification of a HPC mesophase with drying at elevated temperature, solid microparticles are produced that can reflect color across the visible spectrum, from blue to green and red. This method provides a facile and scalable pathway to fabricate structurally colored, edible pigments, which can displace existing synthetic additives used in a wide range of foods and cosmetics. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) derivatives with alkanoyl side chains are known to form thermotropic cholesteric liquid crystals (CLCs) with visible reflection. Although the widely investigated CLCs are requisite for tedious syntheses of chiral and mesogenic compounds from precious petroleum resources, the HPC derivatives easily prepared from biomass resources would contribute to the realization of environment-friendly CLC devices. In this study, we report the linear rheological behavior of thermotropic CLCs of HPC derivatives possessing alkanoyl side chains of different lengths. In addition, the HPC derivatives have been synthesized by the complete esterification of hydroxy groups in HPC. The master curves of these HPC derivatives were almost identical at reference temperatures, with their light reflection at 405 nm. The relaxation peaks appeared at an angular frequency of ~102 rad/s, suggesting the motion of the CLC helical axis. Moreover, the dominant factors affecting the rheological properties of HPC derivatives were strongly dependent on the CLC helical structures. Further, this study provides one of the most promising fabrication strategies for the highly oriented CLC helix by shearing force, which is indispensable to the development of advanced photonic devices with eco-friendliness. [ABSTRACT FROM AUTHOR]

With the overarching aim for the development of sustainable, nontoxic wet strength agents for paper, a novel polymer gel system based on oxidized hydroxypropyl cellulose (keto-HPC) cross-linked with polyamines was investigated in detail to gain a deeper insight into the wet strength mechanism. When applied to paper, this wet strength system significantly increases the relative wet strength by using only low amounts of polymer, and it is therefore comparable with established wet strength agents based on fossil resources, such as polyamidoamine epichlorohydrin resins. With the help of ultrasonic treatment, keto-HPC was degraded with respect to its molecular weight and further cross-linked in paper using polymeric amine-reactive counterparts. The resulting polymer-cross-linked paper mechanical properties were analyzed with respect to the dry and wet tensile strength, respectively. In addition, we analyzed the polymer distribution using fluorescence confocal laser scanning microscopy (CLSM). If high-molecular-weight samples are being used for cross-linking, we do find accumulation of the polymer mainly on the surface of the fibers and at fiber crossing points, accompanied with enhancing strong effects on paper's wet tensile strength. In contrast, if low-molecular-weight (i.e., degraded) keto-HPC is being applied, the macromolecules are capable of entering the inner porous structure of the paper fibers, and almost no accumulation at the fiber crossing points is observed, which also results in a lowered wet paper tensile strength, respectively. This insight into wet strength mechanisms of the keto-HPC/polyamine system can thus lead to new opportunities for the development of alternative biobased wet strength agents where molecular weight dependence of the wet tensile properties allows for a fine tuning of mechanical properties in the wet state. [ABSTRACT FROM AUTHOR]

[Display omitted] Several formulation strategies have been proposed for oral colon delivery, particularly for the therapy of inflammatory bowel disease (IBD). However, targeting the large intestine remains a challenging goal. The aim of this study was to develop and evaluate a novel type of drug delivery system, which is based on multiple drug release triggers for reliable performance. The system consists of: (i) a drug core, (ii) an inner swellable low-viscosity hydroxypropyl methylcellulose (HPMC) layer, and (iii) an outer film coating based on a Eudragit® S:high-methoxyl (HM) pectin (7:3 w/w) blend, optionally containing chitosan. Convex immediate release tablets (2 or 4 mm in diameter) containing paracetamol or 5-aminosalicylic acid (5-ASA) were coated in a fluid bed. The double-coated tablets exhibited pulsatile release profiles when changing the release medium from 0.1 N HCl to phosphate buffer pH 7.4. Also, drug release was faster in simulated colonic fluid (SCF) in the presence of fecal bacteria from IBD patients compared to control culture medium from tablets with outer Eudragit® S: HM pectin: chitosan coatings. The latter systems showed promising results in the control of the progression of colitis and alteration of the microbiota in a preliminary rat study. [ABSTRACT FROM AUTHOR]

The present study assessed the effect of retention on ex vivo skin and in vivo scalp penetration of radiolabeled minoxidil formulations (5% w/v). Minoxidil was radiolabeled with technetium (99mTc) with an efficiency of 99.1% using 0.2% stannous chloride as reducing agent at pH 6 and incubation temperature of 40 °C. Three different 99mTc-minoxidil formulations were prepared using aqueous ethanolic solution as vehicle. Formulation A contains 99mTc-minoxidil dissolved in vehicle, formulation B contains 10% propylene glycol (PG) and formulation C contains 10% hydroxypropyl cellulose (HPC), in addition. Results showed that addition of HPC resulted in enhanced viscosity (400 mPa.s) and significantly higher ex vivo retention (p < 0.05) and permeation (0.75±0.12%, 8 h). PG does not improve the permeation and the results (0.44±0.05%, 8 h) were not significantly different from vehicle alone (0.40±0.05%, 8 h). The results of the in vivo human scalp studies corroborated with the ex vivo results and addition of hydroxypropyl cellulose (HPH) showed significantly higher (p < 0.05) scalp retention. Post 8 h application, scalp penetration in group treated with formulation C was nearly 2.8-fold and 2.2-fold higher than those treated with formulation A and B, respectively. Further, absence of minoxidil in systemic circulation during study duration indicates safety. In conclusion, our results showed that increasing contact time of minoxidil with scalp by modifying viscosity results in reduced frequency of application and improved efficacy. [ABSTRACT FROM AUTHOR]

In the present work, hydroxypropyl cellulose and hematite (α-Fe2O3) nanoparticles (HPC:Fe2O3NPs) composites in various ratios (20:0.5, 20:1, 20:1.5, and 20:2 wt:wt) were synthesised. X-ray diffraction (XRD), scanning electron microscopy (SEM), FTIR spectroscopy, and thermal analysis (DSC, and TGA) were used to examine the structural configuration and thermal properties of the produced composites. The IR crystallinity indices (TCI, LOI, and HBI) were also computed. XRD patterns reveal a mixture of amorphous HPC polymer components and Fe2O3NPs which identifies the relationship between the characteristics of the structure. Distributions and dispersions of Fe2O3NPs on the surface of HPC are apparent in SEM. FTIR absorbance spectra reveal that as the quantity of Fe2O3NPs increased alterations in the intensity, area, and band width were found indicating a change in the molecular configuration of HPC. Variations in the shape, size, and shifts in melting temperature to higher temperatures were found by DSC and TGA when the amount of Fe2O3NPs is increased which could be due to interactions between HPC and Fe2O3NPs. The antibacterial activity of the nanocomposites was tested against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. The composites have good antibacterial activity, confirmed a high potential of antibacterial activity. The findings demonstrated that HPC:Fe2O3NPs composites lead to technological applications in a variety of medical applications. [ABSTRACT FROM AUTHOR]

Hydroxypropyl cellulose (HPC) is a commercially available and biodegradable cellulose derivative, which is known to self‐assemble into chiral nematic liquid crystal phases in water. These features, including liquid crystal‐induced selective reflections in the visible range, make HPC an ideal biopolymer host material for dynamic structural color‐shifting materials. Herein, HPC is used as a starting matrix material and found that, by adding carbon nanotubes (CNT) to an aqueous dispersion of HPC, the color saturation can be improved without influencing the structural color formation and simultaneously conferring electrical conductivity to the material. Additionally, up to 0.4 wt% of cellulose nanofibrils (CNF) can be added to control and tune the rheological properties of the suspension allowing for 3D printability while also maintaining the structural colors. The HPC‐CNT‐CNF printed composite materials show application for flexible color‐changing devices in the form of a dual readout optical and resistive strain sensor and is used as the active material in a dynamic seven‐segment color display. This multipurpose color‐changing material has the potential to be used in the creation of eco‐friendly visual intelligent devices and biodegradable user interfaces and, as such, contributes to the advancement of the field of sustainable and green electronics. [ABSTRACT FROM AUTHOR]

A smart window is an active light control technology that can freely control the transmittance of light, thereby improving the energy efficiency of the interior space and providing a comfortable environment through the control of sunlight from the outside. In this study, a novel smart window that can be utilized as an information‐providing display is developed by a simple light‐blocking technology for existing smart windows. A transparent flexible smart window board is fabricated by inserting a hydroxypropyl cellulose (HPC)–cesium tungsten oxide (CTO) composite hydrogel between two transparent substrates. When the smart window board is irradiated with a near‐infrared (NIR) laser, the heat emitted from the CTO absorbing the NIR energy is transferred to the HPC, thereby changing the visible light transmittance of the HPC. Because only the portion irradiated with the NIR laser can selectively change the visible‐light transmittance, various types of images can be formed in real time. The proposed photo‐driven smart window display can be utilized as a novel platform for window displays that can express various images in real time and can act as a curtain by adjusting the transmittance of light, changing to transparent/opaque, which is oriented in existing smart windows. [ABSTRACT FROM AUTHOR]

Objectives: The current study goal was to come up with an immediate release (IR) formulation for lamotrigine. Lamotrigine is a low soluble and high permeable biopharmaceutical classification class (BCS)-II drug. Method: 4-Hydroxy benzoic acid (4HBA), saccharin sodium (SAC), and methyl paraben (MP) were used as cocrystals formers to form IR tablets of lamotrigine. Variable amounts of L-Hydroxypropyl cellulose (L-HPC) and Croscarmellose sodium in different quantities using factorial design (22) by wet granulation. The amounts of the superdisintegrant (L-HPC and Croscarmellose sodium) X1 and X2 were chosen as independent variables to acquire drug release, respectively. The dependent variables were drug release, hardness, and disintegration time. Results: For each cocrystals formation, four formulations were created (4-HBA, SAC, MP), and a total of 12 formulations were tested utilizing pharmacopoeia limits. All of the factorial batches were found to be within the standard limits. All formulation dissolution characteristics were kinetically fitted, and numerous statistical parameters were established. For the dependent variables, polynomial equations were created and verified. Formulation F11, which contained 10 mg of HPC SSL and 3 mg of Croscarmellose sodium, was the most comparable (similarity factor (f2) =60.86, difference factor (f1) =8.36) to the commercial product (Lamictal). Conclusion: Fickian diffusion, and zero-order kinetics (n = 0.3479) are followed by the optimal formulation (F11). The F11 formulation is used to treat simple and complicated partial seizures as well as generalized tonic-clonic seizures that are resistant to multiple medication treatments. The best formulation shows good retention characteristics, which will ultimately improve the clinical response. [ABSTRACT FROM AUTHOR]

A novel composite hydrogel prepared from polyacrylamide (PAM), polydopamine-modified montmorillonite (PDA@MMT), graphene and hydroxypropyl cellulose (HPC), loaded with Ag NPs, was prepared for the catalytic degradation of methylene blue (MB) and Congo red (CR) using in situ reduction. HPC significantly enhanced the dispersion of PDA@MMT within the hydrogel, endowing the hydrogel with excellent mechanical properties, with stress and strain of 1773 kPa and 4005 %, and elastic modulus and toughness of 43.4 kPa and 29.54 MJ/m3, respectively. The introduction of graphene (GN) increased the rate of electron transfer during the catalytic process and significantly improved the catalytic efficiency, with catalytic rate constants of 1.360 and 0.803 min−1 for MB and CR at 20 °C, respectively. The hydrogels were endowed with excellent antimicrobial properties due to the introduction of Ag NPs. In the future, this hydrogel is expected to play an important role in environmental pollution control. [ABSTRACT FROM AUTHOR]

Obtaining new materials with high water resistance, biodegradability, and adsorption properties is strategic for removing dyes from an aqueous system. In this context, films of biopolymers such as gelatin and hydroxypropyl cellulose (HPC), when combined with clay, offer advantageous properties for environmental remediation. However, despite these benefits, there are no reports of obtaining gelatin/HPC/clay composite materials specifically for adsorbing contaminants in aqueous media. Therefore, composite films consisting of gelatin, HPC, and 0, 2.5, or 5.0 % (w/w) of Montmorillonite clay Cloisite Na+ (NaMt) were obtained using propylene glycol (PG) as plasticizing. The adsorption efficiency of Methylene blue (MB) was evaluated for both crosslinked and non-crosslinked films with and without glutaraldehyde (GA). The results indicated that crosslinking gelatin/HPC films with clay particles resulted in a more compact, smooth, and homogeneous surface, leading to increased water resistance, and improved thermal stability of the films. Additionally, MB adsorption was enhanced, with a maximum adsorption capacity of 11.2 mg g−1 of dye adsorption observed for the crosslinked film of gelatin/HPC with 5.0 % (w/w) clay, corresponding to 89.1 % (w/w) of MB removal from the aqueous phase. This performance was superior to that of films without the crosslinking process. Hence, incorporating clay particles and the crosslinking process played an important role in enhancing MB adsorption on gelatin/HPC surfaces, suggesting that specific interactions between MB molecules and composite films can modulate and broaden the possibilities of removing dyes in wastewater treatment applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Flexible wearable devices have aroused attentions since the booming flexible electronic technologies, as well as the requirements for improved comfortableness and real-time monitoring for complex motion state of human body. Developing a flexible integrated wearable device with multi functions provides a promising route for next-generation wearable devices. Meanwhile, transparency and biocompatibility are also considered a lot. Herein, hydroxypropyl cellulose/silver nanowires (HPC/AgNWs) flexible composite films were fabricated with a facile two-step method. The fabricated composite films exhibited sufficient transparency and mechanical strength. More importantly, the HPC/AgNWs composite films afforded good motion sensing performances with current sensitivity as high as 350 %. It can accurately identify different bending angles and frequencies, and remained stable for more than 1000 bending cycles. Apart from being employed as motion sensors, the fabricated HPC/AgNWs could be also used for electrical heating and electromagnetic shielding. The films could be heated to more than 60°C at 3.0 V in 57 seconds, and the electromagnetic shielding efficiency reached more than 99.9 %. This study contributed a feasible strategy for the preparation of multifunctional flexible films which are expected to be further applicated in the field of wearable devices. [Display omitted] • The HPC/AgNWs composites were prepared using a simple two-step method, fully utilizing the advantages of the two materials. • The HPC/AgNWs composite films have excellent motion sensing sensitivity and durability. • The composite films have the multifunctionality of motion sensing, electrical heating and electromagnetic shielding. [ABSTRACT FROM AUTHOR]

Cannabidiol (CBD) is a natural terpenophenolic compound with known pharmacological activities, but the poor solubility of CBD in water limits its widespread use in medicine and pharmacy. Polymeric (nano)carriers demonstrated high potential for enhancing the solubility and therapeutic activity of lipophilic drugs such as CBD. Here, we report the elaboration of a novel hydroxypropyl cellulose (HPC)-based in situ gelling formulation for controlled delivery of CBD. In the first stage, nanosized polymeric micelles from poly(ethylene oxide)-block-poly(α-cinnamyl-ε-caprolactone-co-ε-caprolactone) (PEO-b-P(CyCL-co-CL) diblock copolymers) were used to increase the solubility of CBD in water. Different copolymers were assessed, and the carrier with the highest encapsulation efficiency (EE) and drug loading capacity (DLC) was selected for further elaboration of nanocomposite in situ gel formulations. Next, the sol-to-gel transition behavior of HPC as a function of K2SO4 concentration in the aqueous solution was investigated by microcalorimetry and dynamic oscillatory rheology, and the optimal formulation capable of forming a physical gel under physiological conditions was determined. Finally, injectable nanocomposite hydrogels comprising cannabidiol were fabricated, and their drug release profile and cytotoxicity against human tumor cell lines were evaluated. The in situ gels exhibited prolonged drug release over 12 h, controlled by gel erosion, and the cytotoxicity of formulated cannabidiol was comparable with that of a free drug.

Along with the increased usage of cellulose in the manufacture of novel materials, those of its derivatives that have good solubility in water or organic solvents have become increasingly important. In this study, hydroxypropyl cellulose (HPC), a cellulosic derivative with distinct features, was utilized to investigate how two of the most-selective oxidation methods currently available in the literature act on the constituent OH groups of both the side chain and the anhydroglycosidic unit in HPC. The oxidation reactions were carried out first using TEMPO, sodium hypochlorite, and sodium bromide, then sodium periodate (NaIO4), for 5 h. A combination of these two protocols was applied. The amount of aldehyde and number of carboxylic groups introduced after oxidation was determined, while the changes in the morphological features of oxidized HPC were, additionally, assessed. Furthermore, utilizing Fourier-transform infrared spectra, X-ray diffraction, and thermogravimetric studies, the chemical structure, crystallinity, and thermal stability of the oxidized HPC samples were examined and compared.

Hydroxypropyl cellulose (HPC) is a water-soluble polymer with many applications in food, pharmaceutical, medical, or paints industries. Past studies have reported that differences in functionality can occur between products of similar pharmaceutical grades. Understanding the origin of these differences is a major challenge for the industry. In this work, the structure and physico-chemical properties of several HPC samples of the same commercial grade were studied. Structural analysis by NMR and enzymatic hydrolysis were performed to study molar substitution and distribution of substituents along the polymer chain respectively. Water-polymer interactions, surface properties as well as rheological and thermal behavior were characterized to tentatively correlate them with the structure, and gain new insights into the structure-function relationship of this polymer. The differences in structure revealed between the samples affect their properties. The unexpected behavior of one sample was attributed to a more heterogeneous substitution pattern, with the coexistence of highly and weakly substituted regions along the same polymer chain. The more block-like distribution of substituents has a great effect on the clouding behavior and surface tension reduction ability of the polymer.