Biodegradable membranes loaded with curcumin to be used as engineered independent devices in active packaging

Anti-Cancer Drug Solubility Development within a Green Solvent: Design of Novel and Robust Mathematical Models Based on Artificial Intelligence

Nowadays, supercritical CO₂(SC-CO₂) is known as a promising alternative for challengeable organic solvents in the pharmaceutical industry. The mathematical prediction and validation of drug solubility through SC-CO₂ system using novel artificial intelligence (AI) approach has been considered as an interesting method. This work aims to evaluate the solubility of tamoxifen as a chemotherapeutic drug inside the SC-CO₂ via the machine learning (ML) technique. This research employs and boosts three distinct models utilizing Adaboost methods. These models include K-nearest Neighbor (KNN), Theil-Sen Regression (TSR), and Gaussian Process (GPR). Two inputs, pressure and temperature, are considered to analyze the available data. Furthermore, the output is Y, which is solubility. As a result, ADA-KNN, ADA-GPR, and ADA-TSR show an R² of 0.996, 0.967, 0.883, respectively, based on the analysis results. Additionally, with MAE metric, they had error rates of 1.98 × 10⁻⁶, 1.33 × 10⁻⁶, and 2.33 × 10⁻⁶, respectively. A model called ADA-KNN was selected as the best model and employed to obtain the optimum values, which can be represented as a vector: (X1 = 329, X2 = 318.0, Y = 6.004 × 10⁻⁵) according to the mentioned metrics and other visual analysis.

Curcumin and its uses in active and smart food packaging applications - a comprehensive review

Active and intelligent food packaging is an innovative technology to prevent food contamination and ensure food quality and safety. Active packaging protects the food from microbial contamination, while smart or intelligent packaging enables monitoring the freshness of the food or quality change in real-time. Curcumin, one of the most well-known natural colorants, has received a lot of attention for its excellent functional properties and ability to change color with changes in pH. Curcumin, the golden component of turmeric, a spice widely used in food since ancient times, is a cost-effective and abundant biomaterial with various biological properties such as antioxidant, antibacterial, antiviral, antitumor, and anti-inflammatory. Recently, active packaging or intelligent packaging systems have been actively developed using the functional properties of curcumin. In this review, we briefly reviewed curcumin's basic biological functions and discussed comprehensive and recent progress in using curcumin in various polymer-based active and smart food packaging applications.

PVDF HFP_RuO2 Nanocomposite Aerogels Produced by Supercritical Drying for Electrochemical Oxidation of Model Tannery Wastewaters

A supercritical CO₂ drying process was used to prepare an innovative nanocomposite, formed by a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF HFP) aerogel loaded with RuO₂ nanoparticles. The produced nanocomposites, at 10% and 60% w/w of RuO₂, were tested for the electrochemical oxidation of model tannery wastewaters. The effect of the electrochemical oxidation parameters, like pH, temperature, and current density, on tannic acid, intermediates, and chemical oxygen demand (COD) removal, was investigated. In particular, the electrolysis of a simulated real tannery wastewater, using PVDF HFP_RuO₂ 60, was optimized working at pH 10, 40 °C, and setting the current density at 600 A/m². Operating in this way, surfactants, sulfides, and tannins oxidation was achieved in about 2.5 h, ammonium nitrogen oxidation in 3 h, and COD removal in 5 h. When chloride-containing solutions were tested, the purification was due to indirect electrolysis, related to surface redox reactions generating active chlorine. Moreover, sulfide ions were converted into sulfates and ammonium nitrogen in gaseous N₂.

Supercritical CO2 Extraction of Organic Solvents from Flunisolide and Fluticasone Propionate

In this work, Class 2 and Class 3 solvents contained in two corticosteroids, flunisolide (Fluni) and fluticasone propionate (Fluti), were reduced to a few ppm by supercritical CO₂ extraction. The process was carried out at pressures from 80 to 200 bar, temperatures of 40 °C and 80 °C, and at a fixed CO₂ flow rate of 0.7 kg/h. The results demonstrated that CO₂ density is the key parameter influencing the extraction kinetics and the solvent final residue. In particular, in the range investigated, optimal pressure and temperature conditions for the extraction of residual organic solvents were found working at 200 bar and 40 °C, which corresponds to a CO₂ density of 0.840 g/cm³. Operating in this way, total organic solvent residues were reduced from 13,671 ppm and 326 ppm to 12 ppm and 10 ppm for Fluni and Fluti, respectively.

Designing active mats based on cellulose acetate/polycaprolactone core/shell structures with different release kinetics

Core/shell electrospun mats based on cellulose acetate (CA) and polycaprolactone (PCL) were developed as novel active materials for releasing quercetin (Quer) and curcumin (Cur). The effect of polymeric uniaxial and coaxial electrospun systems and the chemical structures of Quer and Cur on the structural, thermal, and mass transfer properties of the developed mats were investigated. Release modelling indicated that the diffusion of the active agents from the uniaxial PCL fibers was highly dependent on the type of food simulant. Higher diffusion coefficients were obtained for both active agents in acid food simulant due to the higher swelling of the electrospun mats. In addition, CA/PCL coaxial structures slowed down the diffusion of both active agents into both food simulants. CA increased the retention of the active compounds in the polymer structure, resulting in partition coefficients values higher than the values obtained for uniaxial active PCL mats.

Functional Modification of Cellulose Acetate Microfiltration Membranes by Supercritical Solvent Impregnation

This study investigates the modification of commercial cellulose acetate microfiltration membranes by supercritical solvent impregnation with thymol to provide them with antibacterial properties. The impregnation process was conducted in a batch mode, and the effect of pressure and processing time on thymol loading was followed. The impact of the modification on the membrane's microstructure was analyzed using scanning electron and ion-beam microscopy, and membranes' functionality was tested in a cross-flow filtration system. The antibiofilm properties of the obtained materials were studied against Staphyloccocus aureus and Pseudomonas aeruginosa, while membranes' blocking in contact with bacteria was examined for S. aureus and Escherichia coli. The results revealed a fast impregnation process with high thymol loadings achievable after just 0.5 h at 15 MPa and 20 MPa. The presence of 20% of thymol provided strong antibiofilm properties against the tested strains without affecting the membrane's functionality. The study showed that these strong antibacterial properties could be implemented to the commercial membranes' defined polymeric structure in a short and environmentally friendly process.

Formation of Rutin-β-Cyclodextrin Inclusion Complexes by Supercritical Antisolvent Precipitation

In this work, rutin (RUT)–β-cyclodextrin (β-CD) inclusion complexes are prepared by Supercritical AntiSolvent (SAS) precipitation. Well-defined composite microparticles are obtained at guest:host ratios equal to 1:2 and 1:1 mol:mol. The dimensions of composite particles range between 1.45 ± 0.88 µm and 7.94 ± 2.12 µm. The formation of RUT–β-CD inclusion complexes has been proved by different analyses, including Fourier transform infrared spectroscopy, Differential Scanning Calorimetry, X-ray diffraction, and UV-vis spectroscopy. The dissolution tests reveal a significant improvement in the release rate of RUT from inclusion complexes. Indeed, compared to the unprocessed RUT, the dissolution rate is about 3.9 and 2.4 times faster in the case of the complexes RUT–β-CD 1:2 and 1:1 mol:mol, respectively. From a pharmaceutical/nutraceutical point of view, CD-based inclusion complexes allow the reduction of the polymer amount in the SAS composite formulations.

Polymer-Based Materials Loaded with Curcumin for Wound Healing Applications

Some of the currently used wound dressings have interesting features such as excellent porosity, good water-absorbing capacity, moderate water vapor transmission rate, high drug loading efficiency, and good capability to provide a moist environment, but they are limited in terms of antimicrobial properties. Their inability to protect the wound from microbial invasion results in wound exposure to microbial infections, resulting in a delayed wound healing process. Furthermore, some wound dressings are loaded with synthetic antibiotics that can cause adverse side effects on the patients. Natural-based compounds exhibit unique features such as good biocompatibility, reduced toxicity, etc. Curcumin, one such natural-based compound, has demonstrated several biological activities such as anticancer, antibacterial and antioxidant properties. Its good antibacterial and antioxidant activity make it beneficial for the treatment of wounds. Several researchers have developed different types of polymer-based wound dressings which were loaded with curcumin. These wound dressings displayed excellent features such as good biocompatibility, induction of skin regeneration, accelerated wound healing processes and excellent antioxidant and antibacterial activity. This review will be focused on the in vitro and in vivo therapeutic outcomes of wound dressings loaded with curcumin.

Novel Strategy for Fabricating Multilayer Porous Membranes with Varying Porosity

CO2-assisted polymer compression (CAPC) is a method for fabricating porous polymer materials in which the polymer is plasticized with CO2 and then pressed. In this work, a two-step molding method is adapted, and a porous membrane with multiple layers of varying porosity is fabricated by laminating sheets of a single starting material. A model is constructed in which the expansion owing to CO2 and compression reflected by the longitudinal elastic modulus are considered. The model is constructed based on a two-layer experiment and extended to three layers. From the model simulation, the conditions for fabricating a multilayer porous polymer membrane with three layers of varying porosity (0.6, 0.5, and 0.4) and identical thickness (0.6 mm) are calculated. Finally, a porous membrane with varying porosity is fabricated based on the simulated design.

Supercritical Phase Inversion: A Powerful Tool for Generating Cellulose Acetate-AgNO3 Antimicrobial Membranes

Antimicrobial composite membranes, formed by cellulose acetate loaded with AgNO₃ particles, were produced by supercritical phase inversion. Different cellulose acetate concentrations were tested (15%, 20%, 30%(w/w)), whereas the active agent (i.e., silver nitrate) concentration was fixed at 0.1%(w/w) with respect to the quantity of polymer used. To determine the influence of the process parameters on membranes morphology, the pressure and temperature were varied from 150 to 250 bar and from 55 to 35 °C, respectively. In all cases, regularly porous membranes were produced with a uniform AgNO₃ distribution in the membrane matrix. Silver release rate depended on membrane pore size, covering a time interval from 8 to 75 h.

Anti-microbial activity of curcumin nanoformulations: New trends and future perspectives

Curcumin has been used in numerous anti-microbial research because of its low side effects and extensive traditional applications. Despite having a wide range of effects, the intrinsic physicochemical characteristics such as low bioavailability, poor water solubility, photodegradation, chemical instability, short half-life and fast metabolism of curcumin derivatives limit their pharmaceutical importance. To overcome these drawbacks and improve the therapeutic ability of curcuminoids, novel approaches have been attempted recently. Nanoparticulate drug delivery systems can increase the efficiency of curcumin in several diseases, especially infectious diseases. These innovative strategies include polymeric nanoparticles, hydrogels, nanoemulsion, nanocomposite, nanofibers, liposome, nanostructured lipid carriers (NLCs), polymeric micelles, quantum dots, polymeric blend films and nanomaterial-based combination of curcumin with other anti-bacterial agents. Integration of curcumin in these delivery systems has displayed to improve their solubility, bioavailability, transmembrane permeability, prolong plasma half-life, long-term stability, target-specific delivery and upgraded the therapeutic effects. In this review paper, a range of in vitro and in vivo studies have been critically discussed to explore the therapeutic viability and pharmaceutical significance of the nano-formulated delivery systems to elevate the anti-bacterial activities of curcumin and its derivatives.

Premium ethylcellulose polymer based architectures at work in drug delivery

Premium ethylcellulose polymers are hydrophobic cellulose ether based biomaterials widely employed as biocompatible templates for the design of novel drug delivery systems. They are classified as United States Food and Drug Administration Generally-Recognized-As-Safe chemical substances and have been extensively utilized within the biomedical and pharmaceutical industries for over half a century. They have so far demonstrated the potential to modulate and improve the physiological performance of bioactives leading to the desired enhanced prophylactic and therapeutic outcomes. This review therefore presents a scholarly survey of inter-disciplinary developments focused on the functionalities of ethylcellulose polymers as biomaterials useful for the design of smart delivery architectures for relevant pharmacotherapeutic biomedical applications. Emphasis was placed on evaluating scientific resources related to recent advancements and future directions associated with its applications as delivery systems for drugs and biologics within the past decade thus complementing other specialized reviews showcasing the theme.

SC-CO2-assisted process for a high energy density aerogel supercapacitor: the effect of GO loading

Energy density, safety, and simple and environmentally friendly preparation methods are very significant aspects in the realization of a compact supercapacitor. Herein we report the use of a supercritical CO₂-assisted gel drying process (SC-CO₂) for the preparation of porous electrodes containing dispersed graphene in a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) binder membrane to sandwich in a new portable supercapacitor based on graphene oxide (GO). A GO loading of 60 wt.% was found to give the best combination of factors (porosity, wettability, mechanical and electrochemical properties). Cycling voltammetry and charge/discharge studies showed an excellent capacitance behaviour and stability in an ionic liquid electrolyte, suggesting SC-CO₂ processing as a promising platform to produce highly bulky and porous films for supercapacitors. The supercapacitor device delivers a very high energy density of 79.2 Wh kg^-1 at a power density of 0.23 KW kg^-1 (current density 0.5 A g^-1, specific capacitance 36.2 F g^-1) while that of steel remains at 50.3 Wh kg^-1 at a power density of 2.8 KW kg^-1 (current density 6 A g^-1, specific capacitance 23.5 F g^-1).

Polymer sutures for simultaneous wound healing and drug delivery - A review

Drug delivery using suitable polymeric devices has gathered momentum in the recent years due to their remarkable properties. The versatility of polymeric materials makes them reliable candidates for site targeted drug release. Among them biodegradable sutures has received considerable attention because they offer great promises in the realm of drug delivery. Sutures have been found to be an effective strategy for the delivery of antibacterial agents or anti-inflammatory drugs to the surgical site. Recent developments yielded sutures with improved mechanical properties, but designing sutures with all the desirable properties is still under investigation. This review is an attempt to analyze the recent developments pertaining to biologically active sutures emphasizing their potential as drug delivery vehicle.