Investigation of process/formulation parameters on Inulin-Eudragit RS film properties: correlation between microstructure and film permeability.

Coatings made up of Inulin (Inu) and Eudragit RS (ERS) have been used in the past in colon specific drug delivery systems. In the present study, we investigated the correlation between manufacturing conditions (spraying process and solid content of the film-forming system) and the permeability and the microstructure of Inu-ERS films. The solid content of the polymer dispersion, atomization air pressure, feed rate and bed temperature were investigated by a full factorial design.

Unraveling the loss of lysozyme concentration after tableting.

Therapeutic proteins are fragile compounds whose functions are dependent on their higher-order structure (HOS) formed by specific intramolecular interactions. Nevertheless, protein interactions can also impede the stability if they take place with surfaces or formulation components. Besides chemical and conformational alterations, it can lead to the reduction of free non-complexed protein concentration.

Photodegradation of the antibacterial, antifungal and antiprotozoal drug candidate 2-(2-nitrovinyl) furan (G-0) in solid inclusion complexes with β-cyclodextrin derivatives: Characterization by NMR spectroscopy and in silico toxicity screening.

This work aimed to evaluate the effect of inclusion complex (IC) formation between the drug candidate 2-(2-nitrovinyl) furan (G-0) and hydroxypropyl β-cyclodextrin (HP-β-CD) or sulfobutylether β-cyclodextrin (SBE-β-CD) on the drug's photostability under light exposure. Freeze-dried cyclodextrin inclusion complexes (ICs) and their corresponding physical mixtures were subjected to standardized forced irradiation and light exposure conditions according to ICH guidelines. Kinetic analysis suggested potential alterations in photodegradation pathways.

Insight in the role of resistant starch and Eudragit S 100 in a coating for controlled release in the colonic region.

A dual trigger coating was designed by Ibekwe et al. to achieve site-specific delivery of therapeutics to the colon. It consists essentially of Eudragit® S 100 (EU S 100), a polymer that dissolves above pH 7, and resistant starch, which can only be degraded by enzymes produced by colonic bacteria.

Statistical analysis of long-term physical stability testing of amorphous solid dispersions.

The underlying mechanisms governing amorphous solid dispersions (ASDs) stability are complex and influenced by multiple factors, making it a difficult problem to address comprehensively. The current study investigates how various factors affect the long-term physical stability of ASDs, focusing on both procedural and molecular-level influences. Six drugs were formulated with poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA) as the polymeric carrier, and three preparation methods-two solvent-based processing and one mechanochemical activation-were employed to create the ASDs.

Spray drying for protein stabilization.

During formulation development, stabilizing buffers and excipients are added to therapeutic proteins to overcome their intrinsic instability. Another approach is their solidification using techniques like freeze drying or spray drying (SD). In this work, to enhance the stability of three proteins (α-chymotrypsin, catalase and Horseradish Peroxidase (HRP)), suitable buffers and excipients were selected in solution state for three formulations (referred to as concepts) for each protein using Differential Scanning Fluorimetry (DSF) combined with Static Light Scattering (SLS).

Unraveling the role of pectin biodegradability and blend composition on the permeability of ethylcellulose-based blend films designed for colon targeting.

Polysaccharides have often been used as the biodegradable compound in coated colon specific drug delivery systems. The selection of a specific polysaccharide is critical, as they are degraded by gut bacteria, leading to the site specific release of drugs in the colon. However, it is still not completely understood how bacterial enzymes act on the polysaccharides when they are incorporated in a coating that is primarlily made up of a hydrophobic polymer.

A comprehensive overview of the role of intermolecular interactions in amorphous solid dispersions.

Many recent studies have indicated that drug-polymer intermolecular interactions are an important aspect of amorphous solid dispersions (ASDs) and determine many of the properties of this type of formulations. In this review, a comprehensive overview is given of the latest insights with respect to intermolecular interactions in ASDs. The thermodynamic properties and theoretical considerations of the interactions are discussed, followed by a detailed and critical overview of the various solid-state analysis techniques used to probe interactions at the disposal of the formulation scientist.

The value of spray drying as stabilization process for proteins.

Protein stability in solution state is often poor due to the intrinsic instability of proteins. A solution is to solidify them by using techniques like freeze or spray drying (SD). To shield therapeutic proteins from stress (e.

Molecular miscibility of ASD blend components: an evaluation of (the added value of) solid state NMR spectroscopy and relaxometry.

In order to evaluate the stability of an amorphous solid dispersion (ASD) it is crucial to be able to accurately determine whether the ASD components are homogeneously mixed or not. Several solid-state analysis techniques are at the disposal of the formulation scientist, such as for example modulated differential scanning calorimetry (mDSC) and solid-state nuclear magnetic resonance spectroscopy (ssNMR). ssNMR is a robust, versatile, and accurate analysis technique with a large number of application possibilities.

A Miscibility Study of p(MMA--HEMA)-Based Polymer Blends by Thermal Analysis and Solid-State NMR Relaxometry.

Ternary amorphous solid dispersions (ASDs) consist of a multicomponent carrier with the aim of improving physical stability or dissolution performance. A polymer blend as a carrier that combines a water-insoluble and a water-soluble polymer may delay the drug release rate, minimizing the risk of precipitation from the supersaturated state. Different microstructures of the ternary ASD may result in different drug release performances; hence, understanding the phase morphology of the polymer blend is crucial prior to drug incorporation.

Exploring the influence of hydrogen bond donor groups on the microstructure and intermolecular interactions of amorphous solid dispersions containing diflunisal structural analogues.

Drug-polymer intermolecular interactions, and H-bonds specifically, play an important role in the stabilization process of a compound in an amorphous solid dispersion (ASD). However, it is still difficult to predict whether or not interactions will form and what the strength of those interactions would be, based on the structure of drug and polymer. Therefore, in this study, structural analogues of diflunisal (DIF) were synthesized and incorporated in ASDs with poly(vinylpyrrolidone-co-vinyl acetate) (PVPVA) as a stabilizing polymer.

Encapsulation of Cadmium-Free InP-based Quantum Dots in Cross-Linked Core-Shell Microparticles via Coaxial Electrospraying.

Quantum dots (QDs) are inorganic semiconductor nanocrystals capable of emitting light. The current major challenge lies in the use of heavy metals, which are known to be highly toxic to humans and pose significant environmental risks. Researchers have turned to indium (In) as a promising option for more environmentally benign QDs, specifically indium phosphide (InP).

The influence of hydrogen bonding between different crystallization tendency drugs and PVPVA on the stability of amorphous solid dispersions.

Amorphous solid dispersion (ASD) is one of the formulation strategies for drugs displaying low solubility and low oral bioavailability. In this study, high drug-loaded ASDs of drugs with different crystallization tendencies were prepared by spray drying. The aim was to investigate the influence of hydrogen bonding between the drug and the model polymer PVPVA on the physical stability of ASDs containing drugs with different crystallization tendencies.

Solidification and oral delivery of biologics to the colon- A review.

The oral delivery of biologics such as therapeutic proteins, peptides and oligonucleotides for the treatment of colon related diseases has been the focus of increasing attention over the last years. However, the major disadvantage of these macromolecules is their degradation propensity in liquid state which can lead to the undesirable and complete loss of function. Therefore, to increase the stability of the biologic and reduce their degradation propensity, formulation techniques such as solidification can be performed to obtain a stable solid dosage form for oral administration.

New insights on the effects of blend composition on the biodegradation and permeability of Inulin-Eudragit RS film coatings for colon drug delivery.

Inulin has been applied in Inulin-Eudragit RS (Inu-ERS) coatings as the component responsible for degradation by human microbiota. However, studies on how bacterial enzymes can degrade polysaccharides like inulin imbedded in water insoluble polymers like Eudragit RS are still elusive. The present work aims at elucidating the complex process of enzyme triggered biodegradation of inulin with various molecular weights in isolated films with Eudragit RS.

Encapsulation of Cadmium-Free InP/ZnSe/ZnS Quantum Dots in Poly(LMA-co-EGDMA) Microparticles via Co-flow Droplet Microfluidics.

Quantum dots (QDs) are semiconductor nanocrystals that are used in optoelectronic applications. Most modern QDs are based on toxic metals, for example Cd, and do not comply with the European Restriction of Hazardous Substances regulation of the European Union. Latest promising developments focus on safer QD alternatives based on elements from the III-V group.

Novel cationic cellulose beads for oral delivery of poorly water-soluble drugs.

Cellulose beads emerge as carriers for poorly water-soluble drugs due to their eco-friendly raw materials and favorable porous structure. However, drug dissolution may be limited by their poor swelling ability and the presence of closed pores caused by shrinkage of the pristine cellulose beads. In this study, novel cellulose beads that can swell in acidic environment were prepared by introducing ethylenediamine (EDA) on dialdehyde cellulose (DAC), thereby addressing the shrinkage and closed pore problem of cellulose beads.

The impact of applying an additional polymer coating on high drug-loaded amorphous solid dispersions layered onto pellets.

Inhibiting surface crystallization is an interesting strategy to enhance the physical stability of amorphous solid dispersions (ASDs), still preserving high drug loads. The aim of this study was to investigate the potential surface crystallization inhibitory effect of an additional polymer coating onto ASDs, comprising high drug loads of a fast crystallizing drug, layered onto pellets. For this purpose, bilayer coated pellets were generated with fluid-bed coating, of which the first layer constitutes a solid dispersion of naproxen (NAP) in poly(vinylpyrrolidone-co-vinyl acetate) (PVP-VA) in a 40:60 or 35:65 (w/w) ratio, and ethyl cellulose (EC) composes the second layer.

Evaluation of Different Thermoanalytical Methods for the Analysis of the Stability of Naproxen-Loaded Amorphous Solid Dispersions.

The aim of this research was to investigate three thermoanalytical techniques from the glass transition temperature (T) determination point of view. In addition, the examination of the correlation between the measured T values and the stability of the amorphous solid dispersions (ASDs) was also an important part of the work. The results showed that a similar tendency of the T can be observed in the case of the applied methods.

Complementarity of mDSC, DMA, and DRS Techniques in the Study of and Sub- Transitions in Amorphous Solids: PVPVA, Indomethacin, and Amorphous Solid Dispersions Based on Indomethacin/PVPVA.

Recently, glasses, a subset of amorphous solids, have gained attention in various fields, such as polymer chemistry, optical fibers, and pharmaceuticals. One of their characteristic features, the glass transition temperature () which is absent in 100% crystalline materials, influences several material properties, such as free volume, enthalpy, viscosity, thermodynamic transitions, molecular motions, physical stability, mechanical properties, etc. In addition to , there may be several other temperature-dependent transitions known as sub- transitions (or β-, γ-, and δ-relaxations) which are identified by specific analytical techniques.

Investigating the Potential of Ethyl Cellulose and a Porosity-Increasing Agent as a Carrier System for the Formulation of Amorphous Solid Dispersions.

In the present work, an insoluble polymer, i.e., ethyl cellulose (EC), was combined with the water-soluble polyvinylpyrrolidone (PVP) as a carrier system for the formulation of amorphous solid dispersions.

Gaining Insight into the Role of the Solvent during Spray Drying of Amorphous Solid Dispersions by Studying Evaporation Kinetics.

Spray drying is one of the most commonly used manufacturing techniques for amorphous solid dispersions (ASDs). During spray drying, very fast solvent evaporation is enabled by the generation of small droplets and exposure of these droplets to a heated drying gas. This fast solvent evaporation leads to an increased viscosity that enables kinetic trapping of an active pharmaceutical ingredient (API) in a polymer matrix, which is favorable for the formulation of supersaturated, kinetically stabilized ASDs.

The Value of Bead Coating in the Manufacturing of Amorphous Solid Dispersions: A Comparative Evaluation with Spray Drying.

Despite the fact that an amorphous solid dispersion (ASD)-coated pellet formulation offers potential advantages regarding the minimization of physical stability issues, there is still a lack of in-depth understanding of the bead coating process and its value in relation to spray drying. Therefore, bead coating and spray drying were both evaluated for their ability to manufacture high drug-loaded ASDs and for their ability to generate physically stable formulations. For this purpose, naproxen (NAP)-poly(vinyl-pyrrolidone-co-vinyl acetate) (PVP-VA) was selected as an interacting drug-polymer model system, whilst naproxen methyl ester (NAPME)-PVP-VA served as a non-interacting model system.

Porous soluble dialdehyde cellulose beads: A new carrier for the formulation of poorly water-soluble drugs.

Cellulose beads are porous spherical particles with promising futures for drug delivery applications. In this study, novel dialdehyde cellulose (DAC) beads are developed by periodate oxidation of pristine cellulose for oral delivery of weakly basic poorly water-soluble drugs. Diazepam and itraconazole were studied as model drugs.