Closing Editorial: Advanced Polymeric Materials for Pharmaceutical Applications III.

This Special Issue on "Advanced Polymeric Materials for Pharmaceutical Applications III" brings together innovative research that demonstrates the growing importance of polymeric materials in pharmaceutical sciences [...

Evaluation of the optimal sewage sludge pre-treatment technology through continuous reactor operation: Process performance and microbial community insights.

This study investigated the impact of two low-temperature thermal pre-treatments on continuous anaerobic reactors' performance, sequentially fed with sludge of different total solids content (∼3 % and ∼6 %) and subjected to progressively increasing Organic Loading Rates (OLR) from 1.0 to 2.5 g volatile solids/(L⋅day).

Utilizing Drug Amorphous Solid Dispersions for the Preparation of Dronedarone per os Formulations.

Dronedarone (DRN), an antiarrhythmic drug, exhibits potent pharmacological effects in the management of cardiac arrhythmias. Despite its therapeutic potential, DRN faces formulation challenges due to its low aqueous solubility. Hence, the present study is dedicated to the examination of amorphous solid dispersions (ASDs) as a strategic approach for enhancing the solubility of DRN.

A Review of the Role of Natural Products as Treatment Approaches for Xerostomia.

Xerostomia, commonly known as dry mouth, is a widespread oral health malfunction characterized by decreased salivary flow. This condition results in discomfort, impaired speech and mastication, dysphagia, heightened susceptibility to oral infections, and ultimately, a diminished oral health-related quality of life. The etiology of xerostomia is multifaceted, with primary causes encompassing the use of xerostomic medications, radiation therapy to the head and neck, and systemic diseases such as Sjögren's syndrome.

Comparative study on packing materials for improved biological methanation in trickle Bed reactors.

Packing materials improve biological methanation efficiency in Trickle Bed Reactors. The present study, which lies in the field of energy production and biotechnology, entailed the evaluation of commercial pelletized activated carbon and Raschig rings as packing materials. The evaluation focused on monitoring process indicators and examining the composition of the microbial community.

Optimizing the Distillation of Greek Oregano-Do Process Parameters Affect Bioactive Aroma Constituents and In Vitro Antioxidant Activity?

The aim of the present work was to optimize the conditions of the distillation process at a pilot scale to maximize the yield of specific bioactive compounds of the essential oil of oregano cultivated in Greece, and subsequently to study the in vitro antioxidant activity of these oils. Steam distillation was conducted at an industrial distillery and a Face-Centered Composite (FCC) experimental design was applied by utilizing three distillation factors: time, steam pressure and temperature. Essential oil composition was determined by static headspace gas chromatography-mass spectrometry (HS-GC/MS).

A Review on the Role of Pilocarpine on the Management of Xerostomia and the Importance of the Topical Administration Systems Development.

Xerostomia is linked to an increased risk of dental caries, oral fungal infections, and speaking/swallowing difficulties, factors that may significantly degrade patients' life, socially- or emotionally-wise. Consequently, there is an increasing interest in developing management approaches for confronting this oral condition, at which pilocarpine, a parasympathomimetic agent, plays a vital role. Although the therapeutic effects of orally administrated pilocarpine on the salivary gland flow and the symptoms of xerostomia have been proved by numerous studies, the systemic administration of this drug is affiliated with various adverse effects.

A Review on Xerostomia and Its Various Management Strategies: The Role of Advanced Polymeric Materials in the Treatment Approaches.

The medical term xerostomia refers to the subjective sensation of oral dryness. The etiology seems to be multifactorial with the most frequently reported causes being the use of xerostomic medications, neck and head radiation, and systematic diseases (such as Sjögren's syndrome). Xerostomia is associated with an increased incidence of dental caries, oral fungal infections, and difficulties in speaking and chewing/swallowing, which ultimately affect the oral health-related quality of life.

Optimization of supercritical carbon dioxide explosion for sewage sludge pre-treatment using response surface methodology.

The present work was conducted to assess whether the implementation of Supercritical Carbon dioxide Explosion (SCE) is an efficient approach for sewage sludge pre-treatment. In this context, SCE was optimized with the aim to develop a method attempting to increase the biodegradability of sewage sludge's organic matter content, and thus, to enhance the subsequent anaerobic digestion and methane production. The statistical tool of response surface methodology was applied to evaluate the effects of the main pre-treatment parameters (i.

Valorization of household food wastes to lactic acid production: A response surface methodology approach to optimize fermentation process.

Lactic acid is a valuable compound used in several industrial processes such as polymers, emulsifiers manufacturing, pharmaceutical, and cosmetic formulations. The present study aims to evaluate the potential use of food waste to produce lactic acid through fermentation, both by indigenous microbiota and by the bio-augmentation with two lactic acid bacteria, namely Lactobacillus plantarum BS17 and Lactobacillus casei BP2. Fermentation was studied both in batch and continuously fed anaerobic reactors at mesophilic conditions and a Response Surface Methodology approach was used to optimize the bioprocess performance and determine the environmental parameters (namely pH and time) that lead to the enhancement of lactic acid production during the batch fermentation by indigenous microorganisms.

High-Drug-Loading Amorphous Solid Dispersions via Thermal Cross-Linking: Unraveling the Mechanisms of Stabilization.

This article takes a step forward in understanding the mechanisms involved during the preparation and performance of cross-linked high-drug-loading (HDL) amorphous solid dispersions (ASDs). Specifically, ASDs, having 90 wt % poorly water-soluble drug indomethacin (IND), were prepared via thermal cross-linking of poly(acrylic acid) (PAA) and poly(vinyl alcohol) (PVA) and thoroughly evaluated in terms of physical stability and supersaturation. Results showed that HDL ASDs having excellent active pharmaceutical ingredient (API) amorphous stability and prolonged supersaturation were prepared by fine tuning the cross-linking procedure.

Drug Amorphous Solid Dispersions Based on Poly(vinyl Alcohol): Evaluating the Effect of Poly(propylene Succinate) as Plasticizer.

Although significant actions have been taken towards the utilization of poly(vinyl alcohol) (PVA) in the preparation of drug amorphous solid dispersions (ASDs) using fusion-based techniques (such as melt-quench cooling and hot-melt extrusion), several drawbacks regarding its rather high melting temperature and its thermal degradation profile make the use of the polymer extremely challenging. This is especially important when the active pharmaceutical ingredient (API) has a lower melting temperature (than PVA) or when it is thermally labile. In this vein, a previous study showed that newly synthesized polyester-based plasticizers may improve the processability and the thermal properties of PVA.

Headspace gas chromatography-mass spectrometry in the analysis of lavender's essential oil: Optimization by response surface methodology.

A static headspace gas chromatography - mass spectrometry (HS-GC/MS) method was developed and optimized with the aim to be applied in the analysis of lavender essential oil. To obtain a comprehensive profile of the essential oil, the optimum HS-GC/MS method parameters were selected based on a Design of Experiments (DοE) process. Plackett-Burman experimental design was applied by utilizing seven parameters of the HS injection system.

Electrospun wound dressings containing bioactive natural products: physico-chemical characterization and biological assessment.

Background: Current research on skin tissue engineering has been focusing on novel therapies for the effective management of chronic wounds. A critical aspect is to develop matrices that promote growth and uniform distribution of cells across the wound area, and at the same time offer protection, as well as deliver drugs that help wound healing and tissue regeneration. In this context, we aimed at developing electrospun scaffolds that could serve as carriers for the bioactive natural products alkannin and shikonin (A/S).

Novel electrospun poly-hydroxybutyrate scaffolds as carriers for the wound healing agents alkannins and shikonins.

The aim of this study was to investigate the potential of novel electrospun fiber mats loaded with alkannin and shikonin (A/S) derivatives, using as carrier a highly biocompatible, bio-derived, eco-friendly polymer such as poly[(R)-3-hydroxybutyric acid] (PHB). PHB fibers containing a mixture of A/S derivatives at different ratios were successfully fabricated via electrospinning. Αs evidenced by scanning electron microscopy, the fibers formed a bead-free mesh with average diameters from 1.

Drug crystal growth in ternary amorphous solid dispersions: Effect of surfactants and polymeric matrix-carriers.

The present study evaluates the crystal growth rate of amorphous drugs when dispersed in different ternary polymeric amorphous solid dispersions (ASDs) in the presence of surfactants. Specifically, ternary ASDs of aprepitant (APT, selected as a model drug) were prepared via melt-quench cooling by evaluating three commonly used ASDs matrix/carriers, namely hydroxypropyl cellulose (HPC), poly(vinylpyrrolidone) (PVP) and the copolymer Soluplus® (SOL), and two suitable surfactants, namely d-alpha tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly(ethylene glycol)--poly(propylene glycol)--poly(ethylene glycol) (P407). Results showed that all components were completely miscible (verified hot stage polarized microscopy) and both surfactants were acting as plasticizers to the API.

Leflunomide Sustained Skin Delivery Based on Sulfobetaine-Modified Chitosan Nanoparticles Embedded in Biodegradable Polyesters Films.

The aim of the present study was to prepare a leflunomide (LFD) sustained release transdermal delivery system for the treatment of psoriasis. In this context, LFD-loaded nanoparticles (NPs) based on either neat chitosan (CS) or CS modified with [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SDAEM, a sulfobetaine zwitterionic compound) were initially prepared ionotropic gelation and characterized in terms of in vitro dissolution, physicochemical, and antibacterial properties. Results showed that the use of the SDAEM-modified CS resulted in the formation of LFD-loaded NPs with improved wetting and solubilization properties, better in vitro dissolution profile characteristics (i.

Low Molecular Weight Oligomers of Poly(alkylene succinate) Polyesters as Plasticizers in Poly(vinyl alcohol) Based Pharmaceutical Applications.

The plasticizing effect of three low molecular weight oligomers of aliphatic poly(alkylene succinate) polyesters, namely poly(butylene succinate) (PBSu), poly(ethylene succinate) (PESu), and poly(propylene succinate) (PPSu), on partially hydrolyzed poly(vinyl alcohol) (PVA) used in melt-based pharmaceutical applications, was evaluated for the first time. Initially, the three aliphatic polyesters were prepared by the melt polycondensation process and characterized by differential scanning calorimetry (DSC), H NMR, intrinsic viscosity, and size exclusion chromatography (SEC). Subsequently, their effect on the thermophysical and physicochemical properties of PVA was thoroughly evaluated.

Determination of the physical state of a drug in amorphous solid dispersions using artificial neural networks and ATR-FTIR spectroscopy.

The objective of the present study was to evaluate the use of artificial neural networks (ANNs) in the development of a new chemometric model that will be able to simultaneously distinguish and quantify the percentage of the crystalline and the neat amorphous drug located within the drug-rich amorphous zones formed in an amorphous solid dispersion (ASD) system. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy was used, while Rivaroxaban (RIV, drug) and Soluplus® (SOL, matrix-carrier) were selected for the preparation of a suitable ASD model system. Adequate calibration and test sets were prepared by spiking different percentages of the crystalline and the amorphous drug in the ASDs (prepared by the melting - quench cooling approach), while a 2 full factorial experimental design was employed for the screening of ANN's structure and training parameters as well as spectra region selection and data preprocessing.

Evaluation of rivaroxaban amorphous solid dispersions physical stability via molecular mobility studies and molecular simulations.

The present study evaluates the effect of molecular mobility and molecular interactions in the physical stability of rivaroxaban (RIV) - soluplus® (SOL) amorphous solid dispersions (ASDs). Initially, the use of Adam-Gibbs approach revealed that RIV's molecular mobility (below its glass transition temperature) is significantly reduced in the presence of SOL, while the use of ATR-FTIR spectroscopy showed the formation of hydrogen bonds (HBs) between the two ASD components, indicating that these two mechanisms can be considered as responsible for system's physical stability. Contrary to previously published reports, the utilization of ATR-FTIR spectroscopy in the present study was able to clarify, for the first time, the type of intermolecular interactions formed within the examined ASD system, while the presence of a separate drug-rich amorphous phase (significantly increasing as the content of the drug increases) was also identified.

Experimental, Thermodynamic, and Molecular Modeling Evaluation of Amorphous Simvastatin-Poly(vinylpyrrolidone) Solid Dispersions.

A crucial step for the selection of proper amorphous solid dispersion (ASD) matrix carriers is the in-depth assessment of drug/polymer physicochemical properties. In this context, the present study extends the work of previously published attempts by evaluating the formation of simvastatin (SIM)-poly(vinylpyrrolidone) (PVP) ASDs with the aid of thermodynamic and molecular modeling. Specifically, the implementation of both Flory-Huggins lattice theory and molecular dynamics (MD) simulations was able to predict the miscibility between the two components (a finding that was experimentally verified via differential scanning calorimetry (DSC) and hot stage polarized microscopy), while a complete temperature-concentration phase-transition profile was constructed, leading to the identification of the thermodynamically metastable and unstable ASD zones.

Quality Risk Management and Quality by Design for the Development of Diclofenac Sodium Intra-articular Gelatin Microspheres.

The aim of the present study was to evaluate the development of an intra-articular nonsteroidal anti-inflammatory drug gelatin microsphere formulation based on quality risk management and quality by design approaches. Specifically, after setting the quality target product profile and the critical quality attributes, risk assessment was performed by constructing Ishikawa fishbone diagrams based on preliminary hazard analysis. A Plackett-Burman screening experimental design was applied in order to identify the factors (previously classified by risk assessment analysis as having high risk of failure) having a statistically significant impact on the formation of gelatin microspheres.

Feasibility of multi-hydrolytic enzymes production from optimized grape pomace residues and wheat bran mixture using Aspergillus niger in an integrated citric acid-enzymes production process.

In this study, the potential of the co-generation of hydrolytic enzymes in the biorefinery plant for citric acid fermentation was investigated. Aspergillus niger B60 mycelium along with the solid residue after the recovery of sugars from white pomace (WP') were recycled from citric acid fermentation. A mixture design was used to determine the optimum ternary feedstock mixture composed of WP' (15%), red grape pomace (15%) and wheat bran (70%) that produced the target enzymes with high activities, which were compared to those from pure feedstocks.

Partially hydrolyzed polyvinyl alcohol for fusion-based pharmaceutical formulation processes: Evaluation of suitable plasticizers.

The present study evaluates the effect of several pharmaceutical plasticizers on the thermo-physical and physicochemical properties of partially hydrolyzed poly(vinyl alcohol) (PVA) used in fusion-based pharmaceutical formulation processes. Specifically, the effect of mannitol (MAN), sorbitol (SOR), sucrose (SUC), anhydrous citric acid (CA), triethyl citrate (TEC) and low-molecular weight polyethylene glycol (PEG400) on PVA's melting properties, physical state and thermal degradation was evaluated via differential scanning calorimetry (DSC), powder X-ray diffractometry (pXRD) and thermo-gravimetric analysis (TGA). Results showed that the use of MAN, SOR, SUC and PEG400 led to the reduction of PVA's melting onset temperature, while MAN, SUC, CA and SOR were amorphously dispersed within PVA's matrix, and the addition of SUC and CA resulted in significant reduction of PVA's crystallinity.