Hydroxypropyl Cellulose Research Articles

Insight into the Role of Hydroxypropyl Cellulose in Tuning Crystallization Behaviors of dl-Methionine

Insight into the Role of Hydroxypropyl Cellulose in Tuning Crystallization Behaviors of <scp>dl</scp>-Methionine

Cesium tungsten oxide-carbon nanotube-hydroxypropyl cellulose thermoresponsive display.

Among different heat-responsive polymers, hydroxypropyl cellulose (HPC) is biodegradable and is widely used in products that are harmless to the human body, such as food and pharmaceuticals. When the temperature of the hydrogel-type HPC increases, the hydrophilic bonds between the HPC molecules break, and the HPC molecules aggregate owing to the hydrophobic bonds. Therefore, light transmittance may vary because the aggregated HPC molecules scatter light. This study investigated the implementation of a display using the thermoreversible phase transition of HPC. Herein, a near-infrared (NIR) laser was irradiated only to a local area to control the surface temperature and enable the effective operation of the thermoreversible phase transition of HPC. For this, cesium tungsten oxide (CTO), which absorbs NIR light and generates heat, was mixed with the HPC hydrogel to improve the photothermal effect. Moreover, by additionally mixing carbon nanotubes (CNTs) with high thermal conductivity, the heat generated from the CTO is quickly transferred to the HPC hydrogel, and the heat of the HPC hydrogel is quickly cooled through the CNTs after stopping the NIR laser irradiation. The produced NIR-writing CTO-CNT-HPC (CCH) thermoresponsive display exhibited a fast thermoresponsive time. The CCH thermoresponsive display developed in this study can be applied in situations that require fast display response times, such as interactive advertising, property exhibitions, navigation systems for car, schedule information, event information, and public announcements.

Hydroxyl group of cellulose derivatives in promoting Li+ transport mechanism in solid polymer electrolyte membrane

The incorporation of nanocellulose (NC) with cellulose derivatives, specifically hydroxypropyl methylcellulose (HPMC), hydroxypropyl cellulose (HPC), and hydroxyethyl cellulose (HEC), resulting in a solid polymer electrolyte (SPE).

A thermo-responsive hydrogel for body temperature-induced spontaneous information decryption and self-encryption.

A thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) hydrogel, exhibiting an interesting phenomenon of an opaque-transparent-opaque transition in the successive processes of heating and cooling, is reported. It is fabricated by means of both the porogenic effect of hydroxypropyl cellulose and the cononsolvency effect of PNIPAM in a mixed solvent of dimethyl sulfoxide and water. After being mildly triggered by body temperature, the hydrogel is used to spontaneously decrypt the quick response code within 4 min and then autonomously encrypts the code again within 10 min at room temperature. The mechanism for the transient transparency of hydrogels during the quenching process has been elucidated.

Design of remoldable, shape-memory, welded biomass composites based on the acetal bond of the cellulose chain

The growing environmental concern over petrochemical-based plastics continuously promotes the exploration of green and sustainable biomass-based covalent adaptable networks composites (CANs). Compared with petrochemical products, cellulose and its derivatives have overwhelming superiority in terms of availability, cost and biodegradability; nevertheless, CANs using the abundant acetal bonds in the cellulose chain rather than elaborately designing other types of dynamic covalent bonds still have not received sufficient attention. Herein, we report acetal-based cellulose covalent adaptable networks (ACC) synthesized with poly(ethylene glycol) diglycidyl ether as the crosslinker for hydroxypropyl cellulose and tetrabutylammonium bromide (TBAB) as an accelerant. For the first time, exchangeability of the cellulose chain acetal reversible bonds at elevated temperature have been demonstrated to endow ACC reprocessability, shape memory and welding. The TBAB has been used as an accelerant of dynamic exchange for acetal bonds first and its accelerating mechanism and advantages have also been investigated. In addition, the thermal, mechanical and hydrophilic properties of ACC can be adjusted by simply adjusting the raw material ratio and the ACC has excellent chemical and biodegradability. Hence, ACC will provide new ideas for solving white pollution and building new CANs.

Dess-Martin oxidation of hydroxypropyl and hydroxyethyl cellulose, and exploration of their polysaccharide/polypeptide hydrogels

Oxidation of polysaccharides can provide biomaterials with aldehyde and ketone functional groups, which are particularly useful in biomedical applications, like drug delivery, tissue adhesion and hydrogel preparation. However, despite their potential, only a few such methods have been reported, and achieving selective, quantitative oxidation of polysaccharides remains challenging. Herein we report utilization of a mild oxidant, Dess-Martin periodinane, for the chemoselective oxidation of hydroxypropyl cellulose (HPC) and hydroxyethyl cellulose (HEC). Our findings reveal that the oxidation of HPC is fast, efficient and achieves near-quantitative conversion. Moreover, both Ox-HPC and Ox-HEC exhibit low cell toxicity, and readily form hydrogels by reaction with a polypeptide comprising amino acids with amine-containing a-substituents, α-poly-l-lysine. The peptide/polysaccharide hydrogels display self-healing properties, injectability, and antimicrobial activity, making them highly attractive for biomedical applications including in wound dressings.

Ionic conductive konjac glucomannan/liquid crystal cellulose composite hydrogels with dual sensing of photo- and electro-signals capacities as wearable strain sensors

The ionic conductive hydrogel-based sensor exhibits wide applications in wearable electronic devices. However, the strength and ductility trade-off, multimodal requirements, and water-soluble polymer alternatives are significant challenges for the hydrogel-based sensor. Herein, a stretchable and conductive hydrogel is developed with a double network formed by incorporating polyacrylamide and ionic liquid into the konjac glucomannan network. The hydrogel displays significantly enhanced mechanical properties, and good tear/puncture resistance owing to the existence of covalent and non-covalent interactions. In addition, by the introduction of nematic liquid crystal hydroxypropyl cellulose, the hydrogel/cellulose-based strain sensor demonstrates excellent sensing performance in monitoring human motions and writing recognition ability with optical and electrical bimodal sensing response. This work provides new insights to further expand the options of hydrogel-based sensor matrix and to construct bimodal sensors.

Development, Optimization and Characterization of Glimepiride Nanosuspension with Improved Solubility and Dissolution

Current work describes the development of nanoparticulate suspension (NPs) of glimeperide (GLMP) with enhanced solubility and bioavailability. Using the ultrasonication-assisted precipitation method, GLMP-NP was developed and optimized through the use of a three-factor two-level full factorial design methodology. Drug release, size of a particle, and encapsulation efficiency from nanoparticles were considered as dependent variables while the concentration of Hydroxy propyl cellulose (HPC SSL), Kollicoat IR, and sonication time were considered as independent variables. According to the study, every independent variable significantly affected the dependent variables (p &lt;0.05). The size of the particle GLMP-NP ranged between 159 (F2) to 505 nm (F8) while EE varied from 32 (F8) to 75% (F2). The DR of the GLMP-NP observed at 10 min ranged between 35 (F8) to 100% (F2). A significant enhancement in dissolution rate was observed in GLMP-NPs (F1-F8) in comparison to pure GLMP. It was discovered that pure GLMP dissolved in 27.25 ± 6.8 μg/mL of double-distilled water, while GLMP-NP exhibited 3.50 to 6.58-fold enhancement in saturation solubility. FTIR and DSC analysis revealed excellent compatibility between GLMP and excipients. XRD study confirmed the amorphous nature of the nanoparticles while SEM analysis revealed a smooth surface. In conclusion, this study demonstrates the substantial improvement in dissolution rate and solubility of pure GLMP when formulated as nanoparticles.

Highly efficient functionalization of hydroxypropyl cellulose with glucuronic acid through click chemistry under microwave irradiation as potential biomaterial with therapeutic properties

A straightforward and effective method to chemically conjugate hydroxypropyl cellulose (HPC) to GlcA is described via microwave assisted copper-catalyzed azide-alkyne cycloaddition reaction (CuAAC) between the azide functionalized HPC and the alkynyl functionalized GlcA, reducing reaction times from 24 h to 2 h. Two types of HPC azide derivatives, including an ester (ES) or a carbamate (CB) functional group, were synthesized and characterized by FT-IR and NMR spectroscopy that revealed the efficiency in the incorporation of the azide moieties in the cellulose backbone. These compounds were then conjugated with the alkynyl GlcA by CuAAC, affording the desired glycopolymers, HPA-ES-GlcA and HPA-CB-GlcA in excellent yields. The whole process involved rapid and effective reactions as well as easy purification techniques, using mostly non-toxic solvents, contributing to the sustainability of the synthesis These glycopolymers were characterized by FT-IR, NMR, TGA, DTA and SEM. Furthermore, the cytotoxicity, anti-inflammatory and antibacterial properties of the new glycopolymers were tested and it was found that these new HPC-GlcA conjugates presented low cytotoxicity, good anti-inflammatory and antibacterial properties. Overall, our results showed that HPC-GlcA polymers are suitable as potential GAG mimics for biomedical applications, therefore further investigations will be carried out.

Reductive amination of oxidized hydroxypropyl cellulose with ω-aminoalkanoic acids as an efficient route to zwitterionic derivatives

Zwitterionic polymers, with their equal amounts of cationic and anionic functional groups, have found widespread utility including as non-fouling coatings, hydrogel materials, stabilizers, antifreeze materials, and drug carriers. Polysaccharide-derived zwitterionic polymers are attractive because of their sustainable origin, potential for lower toxicity, and possible biodegradability, but previous methods for synthesis of zwitterionic polysaccharide derivatives have been limited in terms of flexibility and attainable degree of substitution (DS) of charged entities. We report herein successful design and synthesis of zwitterionic polysaccharide derivatives, in this case based on cellulose, by reductive amination of oxidized 2-hydroxypropyl cellulose (Ox-HPC) with ω-aminoalkanoic acids. Reductive amination products could be readily obtained with DS(cation) (= DS(anion)) up to 1.6. Adduct hydrophilic/hydrophobic balance (amphiphilicity) can be influenced by selecting the appropriate chain length of the ω-aminoalkanoic acid. This strategy is shown to produce a range of amphiphilic, water-soluble, moderately high glass transition temperature (Tg) polysaccharide derivatives in just a couple of efficient steps from commercially available building blocks. The adducts were evaluated as crystallization inhibitors. They are strong inhibitors of crystallization even for the challenging, poorly soluble, fast-crystallizing prostate cancer drug enzalutamide, as supported by surface tension and Flory–Huggins interaction parameter results.

CONSERVATION PROCESSES OF A WOODEN COFFIN COVERED WITH A BLACK RESIN LAYER AND COLORED MATERIALS IN DAHSHUR ARCHAEOLOGICAL AREA

This paper describes the results of a multi-technological analytical protocol performed on the painted surface of an Egyptian wooden coffin and documents the conservation processes of a wooden coffin covered with a black resin layer and coloured materials in Dahshur Archaeological Area dating back to the late period. It uses visual observation, optical microscopy (OM), technical imaging, 2D and 3D programmes, and a scan made using an electron microscope coupled with an Energy Dispersive X-ray (SEM-EDX), X-ray diffraction (XRD). Wood identification was also carried out. The results showed the use of yellow ochre for the yellow painted layer; the ground layer was calcium carbonate with gypsum, and the fabric layer was linen. The conservation processes of the wooden coffin included mechanical and chemical cleaning; reassembling the separated wooden parts, ground layer, and black resin layers; filling the edge of the ground layer; and consolidating the wood, black resin, and painted layer. The conservation processes included mechanical cleaning using soft brushes, chemical cleaning using xylene and distilled water for the black resin layer and ethyl alcohol and distilled water for the painted layer, stabilisation of the separated ground layer using Paraloid B72, filling the cracks of the ground layers using glass microballoons with Paraloid B72, and consolidating the painted layer with nano-silica with Klucel G (hydroxypropyl cellulose) (0.5% concentration).

Skin‐Like Transparent, High Resilience, Low Hysteresis, Fatigue‐Resistant Cellulose‐Based Eutectogel for Self‐Powered E‐Skin and Human–Machine Interaction

AbstractArtificial electronic skin (E‐skin), a class of promising materials mimicking the physical‐chemical and sensory performance of the human skin, has gained extensive interest in the field of human health‐monitoring and robotic skins. However, developing E‐skin simultaneously achieving high resilience, hysteresis‐free, and absent external power is always a formidable challenge. Herein, a liquid‐free eutectic gel‐based self‐powered E‐skin with high resilience, fatigue resistance, and conductivity is prepared by introducing hydroxypropyl cellulose (HPC) into metal salt‐based deep eutectic solvents (MDES). The unique structural design of cellulose‐anchored permanent entangled poly(acrylic acid) (PAA) chain, in combination with rapid broken/reconstruction of the dense dynamic sacrificial bonds, realizes the fabrication of high‐elastic E‐skin with negligible hysteresis. This further demonstrates the promising practical application of the cellulose‐based eutectogel with high transmittance (92%), high conductivity (36.6 mS m−1), and high resilience (98.1%), and excellent environment stability in robust triboelectric nanogenerator for energy harvesting and high resilience, self‐powered E‐skin for human health‐caring and human‐machine interaction.

Fabrication and in vitro characterization of delafloxacin-laden electrosprayed hydroxypropyl cellulose nanoparticulated solid dispersions for enhanced aqueous solubility and release rate of the drug

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.

Toward Sustainable Electronics: Exploiting the Potential of a Biodegradable Cellulose Blend for Photolithographic Processes and Eco‐Friendly Devices

Flexible electronics has emerged as a promising field for the development of electronic devices with applications in wearables, biomedical sensors, and edible electronics. Biomaterials play a crucial role in fabricating flexible substrates, and the utilization of polymer blends offers exciting possibilities for tuning mechanical and chemical properties. This paper highlights the potential of a novel polymer blend based on ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) in the fabrication of substrates for flexible electronics. By blending the two cellulose ethers, it is possible to tune the mechanical and chemical properties of the final substrate, tailored to meet specific requirements. To exploit such innovative green substrates for photolithographic processes, their stability, and processability is extensively investigated. The feasibility of photolithographic processes on such biodegradable and edible substrates is demonstrated by fabricating both resistive and capacitive sensors through standard photolithographic processes, presenting a breakthrough in terms of applicability. The utilization of such biomaterials holds tremendous potential for driving technological advancements in various fields. These materials pave the way for innovative devices catering to diverse applications, from agriculture to food and biomedicine. Importantly, they also promote a sustainable approach for their fabrication, laying the foundation for an environment‐aware future of technological progress.

The engineering, drug release, and in vitro evaluations of the PLLA/HPC/Calendula Officinalis electrospun nanofibers optimized by Response Surface Methodology

A system based on poly(l-lactic acid) (PLLA) and hydroxypropyl cellulose (HPC) was considered in this study to achieve electrospun mats with outstanding properties and applicability in biomedical engineering. A novel binary solvent system of chloroform/N,N-dimethylformamide (CF/DMF:70/30) was utilized to minimize the probable phase separation between the polymeric components. Moreover, Response Surface Methodology (RSM) was employed to model/optimize the process. Finally, to scrutinize the ability of the complex in terms of drug delivery, Calendula Officinalis (Marigold) extract was added to the solution of the optimal sample (Opt.PH), and then the set was electrospun (PHM). As a result, the presence of Marigold led to higher values of fiber diameter (262 ± 34 nm), pore size (483 ± 102 nm), and surface porosity (81.0 ± 7.3 %). As this drug could also prohibit the micro-scale phase separation, the PHM touched superior tensile strength and Young modulus of 11.3 ± 1.1 and 91.2 ± 4.2 MPa, respectively. Additionally, the cumulative release data demonstrated non-Fickian diffusion with the Korsmeyer-Peppas exponent and diffusion coefficient of n = 0.69 and D = 2.073 × 10−14 cm2/s, respectively. At the end stage, both the Opt.PH and PHM mats manifested satisfactory results regarding the hydrophilicity and cell viability/proliferation assessments, reflecting their high potential to be used in regenerative medicine applications.

Phase homogeneity in ternary amorphous solid dispersions and its impact on solubility, dissolution and supersaturation – Influence of processing and hydroxypropyl cellulose grade

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.

3D-printed prednisolone phosphate suppositories with tunable dose and rapid release for the treatment of inflammatory bowel disease

Established medicines are often not tailored to the needs of the pediatric population, causing difficulties with administration or dosing. Three-dimensional (3D) printing technology allows novel approaches for compounding of personalized medicine, as is exemplified in this study for the automated compounding of rectal preparations for children. We investigated the material requirements to print prednisolone phosphate-loaded suppositories with tunable dose and rapid drug release for the treatment of inflammatory bowel diseases. Three formulations containing 4 % w/w prednisolone sodium phosphate (PSP) and different amounts of hydroxypropyl cellulose (HPC) and mannitol as excipients were printed as suppositories with a fused deposition modeling (FDM) 3D-printer. Dissolution studies showed that the PSP release rate was increased when higher weight fractions of mannitol were added as a pore former, with 90 % drug release within 30 min for mannitol 48 % w/w. We further printed suppositories with 48 % mannitol with different infill densities and dimensions to tune the dose. Our findings demonstrated that 3D-printed suppositories with PSP doses ranging from 6 to 30 mg could be compounded without notably affecting the dissolution kinetics, ensuring equivalent therapeutic efficacies for different doses.

Addition of Silver Nanoparticles to Composite Edible Films and Coatings to Enhance Their Antimicrobial Activity and Application to Cherry Preservation.

The aim of this study was to examine the potential enhancement of the antimicrobial activity of edible films, composed of (i) chitosan (CH), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%) and (ii) hydroxypropyl methylcellulose (HPMC), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%), with silver nanoparticle (AgNP) incorporationat levels 5, 10 and 15% v/v. According to the results, the AgNP addition led to very high antimicrobial activity of both films, reducing by more than 96% the microbial growth of the Gram-negative bacterium Escherichia coli (E. coli) in all cases. On the other hand, by adding AgNPs to films, their thickness as well as oxygen and water vapor permeability decreased, while their transparency increased. Furthermore, the contribution of these specific edible films to preserve cherries under cold storage was investigated. All edible coatings resulted in an improvement of the fruit properties under consideration, and especially the color difference, hardness and total microbial load.

In Situ Gelling Hydroxypropyl Cellulose Formulation Comprising Cannabidiol-Loaded Block Copolymer Micelles for Sustained Drug Delivery.

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.

Title High Solar-Thermal Conversion Aerogel for Efficient Atmospheric Water Harvesting.

The shortage of freshwater is a global problem, however, the gel that can be used for atmospheric water harvesting (AWH) in recent years studying, suffer from salt leakage, agglomeration, and slow water evaporation efficiency. Herein, a solar-driven atmospheric water harvesting (SAWH) aerogel is prepared by UV polymerization and freeze-drying technique, using poly(N-isopropylacrylamide) (PNIPAm), hydroxypropyl cellulose (HPC), ethanolamine-decorate LiCl (E-LiCl) and polyaniline (PANI) as raw materials. The PNIPAm and HPC formed aerogel networks makes the E-LiCl stably and efficiently loaded, improving the water adsorption-desorption kinetics, and PANI achieves rapid water vapor evaporation. The aerogel has low density ≈0.12-0.15gcm-3, but can sustain a weight of 1000 times of its own weight. The synergist of elements and structure gives the aerogel has 0.46-2.95gg-1 water uptake capability at 30-90% relative humidity, and evaporation rate reaches 1.98kgm-2h-1 under 1 sun illumination. In outdoor experiments, 88% of the water is harvesting under natural light irradiation, and an average water harvesting rate of 0.80gwater gsorbent -1day-1. Therefore, the aerogel can be used in arid and semi-arid areas to collect water for plants and animals.