Ethylene-acrylic Copolymer Research Articles

Application of press-coatings for the development of prolonged release tablets based on hygroscopic substances

Introduction. The development of universal approaches to work with hygroscopic substances is an urgent task of pharmaceutical technology. Coating of tablets with hygroscopic substances deserves special attention. Pressed coatings represent a promising method for coating hygroscopic tablets. Such coating can contribute both to imparting the specified release characteristics to the tablet, and to the protection of APS from environmental factors, as well as can be an alternative to obtaining matrix tablets of prolonged action with hygroscopic substances in those cases when direct contact of APS with the polymeric carrier is undesirable.Aim. Study of the possibility of using pressed coatings to control the kinetics and release site of hygroscopic substances from tablets using DEAE as an example.Materials and methods. The object of the present study was the substance bis{2-[(2Z)-4-hydroxy-4-oxobut-2-enoyloxy]-N,N-diethylethanaminium} butanedioneate (DEAE), shellac (BonuLac®, Biogrund GmbH, Germany); copolymer of methacrylic acid and ethyl acrylate (AquaPolish® 712, Biogrund GmbH, Germany); copolymer of polyvinylpyrrolidone and polyvinyl acetate (Kollidon® SR, BASF, Germany), ethyl cellulose (Acros Organics, USA). Lactose monohydrate (Tablettose® 80, Meggle AG, Germany) was added to the formulations as an excipient. The superdisintegrant crospovidone XL and the lubricant sodium stearyl fumarate (JRS, Germany) were used to improve disintegration.Results and discussion. The properties of the pressed coatings were studied. Shellac-based coating mixture may be suitable for obtaining enteric soluble coating for dissolution in medium with pH 4.5. PVP and PVA copolymer does not provide stability of coatings in acidic medium, but its introduction into formulations with ethyl cellulose, as well as into formulations with copolymer of methacrylic acid and ethyl acrylate allows to achieve uniform release in all media within 5 hours.Conclusion. The study showed the possibility of using pressed coatings to control the kinetics of API release. The coating obtained using this technology can be used for hygroscopic substances. This method is a useful alternative when it is necessary to separate the matrix-forming polymer and the API, which have synergistic hygroscopic properties.

Hydroesterification of Polycyclooctene to Access Linear Ethylene Ethyl Acrylate Copolymers as a Step Toward Polyolefin Functionalization

Hydroesterification of Polycyclooctene to Access Linear Ethylene Ethyl Acrylate Copolymers as a Step Toward Polyolefin Functionalization

Tailored Interaction between Cellulose Nanowhiskers and Core-Shell Particles Determines the Optical and Mechanical Properties in Hybrid Films.

Hybrid materials of core-shell particles and cellulose nanowhiskers (CNWs) were synthesized to produce opal films with increasing tensile strength. After the incorporation of CNWs into the processed particle films, differences in the mechanical and optical properties were noticeable, which stemmed from the adhesion forces between the cellulose and the particles' shell material. Two different particle compositions were compared, using polystyrene as cores, and either poly(ethyl acrylate) (PEA) or a copolymer of ethyl acrylate and 3 wt % of 2-hydroxyethyl methacrylate (HEMA) as the shell material. Stronger interactions between the particles containing HEMA and the CNWs were displayed via atomic force microscopy particle manipulation experiments, where higher forces were required to deliberately move P(EA-co-HEMA) particles on a CNW substrate compared to PEA particles. The stronger interaction behaviors increased the disorder of the particles within the opal films toward photonic glasses with angle-independent structural colors. Also, the increase in tensile strength from <1 MPa at a cellulose content of 0 wt % to 6 MPa at the optimal CNW content of 15 wt % was more pronounced compared to the particle-cellulose mixture with only PEA in the particle shell. Thus, the presence of the hydroxy groups in the particles' shell material on the molecular level significantly influenced the optical and mechanical properties on the macroscopic level.

Real-time in vivo monitoring of the antimicrobial action of combination therapies in the management of infected topical wounds

The increasing prevalence of non-healing infected wounds has become a serious concern in the clinical practice, being associated to population aging and to the rising prevalence of several chronic conditions such as diabetes. Herein, the evaluation of the bactericidal and antibiofilm effects of the natural antiseptic terpenes thymol and farnesol standing alone or in combination with the standard care antiseptic chlorhexidine was carried out both in vitro and in vivo. The in vitro combinatorial treatment of chlorhexidine associated with those terpenes against Staphylococcus aureus in its planktonic and sessile forms demonstrated a superior antibacterial activity than that of chlorhexidine alone. Real-time in vivo monitoring of infection progression and antimicrobial treatment outcomes were evaluated using the bioluminescent S. aureus strain Xen36. In vivo studies on infected wound splinting murine models corroborated the superior bactericidal effects of the combinatorial treatments here proposed. Moreover, the encapsulation of thymol in electrospun Eudragit® S100 (i.e., a synthetic anionic copolymer of methacrylic acid and ethyl acrylate)-based wound dressings was also carried out in order to design efficient antimicrobial wound dressings.

Influence of talc and hydrogenated castor oil on the dissolution behavior of metformin-loaded pellets with acrylic-based sustained release coating

Multi-unit pellet system (MUPS) is of great interest as it is amenable to customization. MUPS comprises multi-particulates, usually as pellets or spheroids, which can be coated with diffusion barrier coatings. One commonly used diffusion barrier coating is the methacrylic acid copolymer, which can be used as a taste masking, enteric or sustained release polymer. While the versatility of methacrylic acid copolymers makes them pliable for pellet coating, there are impediments associated with their use. Additives commonly required with this polymer, including plasticizer and anti-adherent, have been shown to weaken the film strength. The objective of this study was to investigate the impact of osmotic pressure within the core on the sustained release coat integrity and functionality. Hydrogenated castor oil (HCO) was chosen as the additive to be studied. Metformin-loaded pellets, prepared via extrusion-spheronization, were coated with ethyl acrylate and methyl methacrylate copolymer (Eudragit RS 30 D) containing talc, talc-HCO, or HCO to different coat thicknesses. Drug release was investigated using the USP dissolution apparatus 2 and an ultraviolet imager. The swelling of the pellets when wetted was monitored by video imaging through a microscope. When coated to 7.5 % coat weight gain, coats with HCO slowed down drug release more than the other pellets. The pellets also swelled the most, which suggests that they were more resistant to the osmotic pressure exerted by metformin. For drugs which exert high osmotic pressure, HCO can serve as an efficient alternative to talc in the preparation of methacrylic acid copolymer coatings.

Polymerization Chemistry of Vinylboronic Acid Derivatives: Boron-Based Monomer Design and Polymer Reaction through Side-Chain Replacement

In chain-growth polymerization, (co)polymerization abilities of monomers are heavily dependent on the element or functional group attaching to vinyl moiety, resulting in the limitation of accessible polymers. The replacement of the element on the polymer main chain could lead to access new class of polymers with overcoming the synthetic limitations. Herein, we describe the usability of alkenylboronic acid derivatives as the monomers for radical polymerization and post-polymerization transformation through carbon-boron bond-cleaving side-chain replacement. The key for radical polymerization ability of alkenyl boronate was vacant p-orbital of boron for moderate stabilization of chain growth radical. The alkenyl boronate monomers are usable for copolymerization with common monomers as well as for RAFT polymerization. The C-B bond transformation allows syntheses of conventionally inaccessible polymers, such as poly(α-methyl vinyl alcohol), poly(α-methyl vinyl amine), styrene-vinyl alcohol copolymer, and ethylene-acrylate copolymer. Boron on the polymer main chain was also used as the trigger for stimuli-responsive backbone degradation of methacrylate polymer through C-B bond homolysis and β-scission. Thus, alkenyl boronate monomers have an impact on not only breakthrough of the limitation in polymer synthesis but also development of novel polymer functions.

Unusual Stress Upturn in Elastomers Prepared Using Macro Cross-Linkers with Multiple Vinyl Side Groups.

In this study, the unique tensile properties of acrylate elastomers prepared using macro cross-linker polymers with multiple vinyl side groups are analyzed. For the preparation of the macro cross-linker, poly(ethyl acrylate) copolymers bearing hydroxy functional groups are synthesized, followed by the hydroxy-isocyanate reaction with 2-isocyanatoethyl acrylate. Subsequently, the elastomers samples are prepared by UV polymerization of ethyl acrylate in the presence of the macro cross-linkers. The tensile properties of the elastomers in the small elongation region are similar to those of typical elastomers prepared using divinyl cross-linkers, whereas the stress upturn in the large elongation region is considerably different. The stress upturn varies based on the fraction of vinyl side groups in the macro cross-linkers, whereas stress in the small elongation region remains unchanged. These properties are analyzed using various theoretical models. The results reveal that there is artificial inhomogeneity in the cross-link density for samples prepared by the macro cross-linkers, where the short poly(ethyl acrylate) strands inside the macro cross-linker limit the overall chain stretchability. On the whole, this study demonstrates a new method for tuning elastomer properties, especially at large deformation.

Synthesis and testing of latex properties of copolymers of ethyl or butyl acrylate with methyl or butyl methacrylate and methacrylic acid

AbstractThe results of a study on latexes obtained by emulsion copolymerization of acrylic, methacrylic and vinyl monomers without surfactants are presented. The monomers included ethyl acrylate and butyl acrylate, methyl and butyl methacrylate and methacrylic acid. The yield of the copolymerization reaction, the polymer concentration in the latex, the pH, surface tension, intrinsic viscosity number, Huggins constant, the molecular weight of the polymer and the particle size in the latex were determined. The stability of the latexes was tested by determining the values of non‐overt and overt coagulation thresholds. The values of the limiting equivalent conductivity and the anode zeta potential were determined. The relative hardness of latex membranes and their mass change after hot water extraction were investigated. The relationships between the properties of individual latexes were established. The main aim of the research was to determine the influence of copolymer composition on the electrokinetic properties of polymer particles in latex. They determine the possibility of developing a new type of paint for electrophoretic painting with the use of latexes. © 2022 Society of Industrial Chemistry.

Relaxation and Amorphous Structure of Polymers Containing Rigid Fumarate Segments.

The physical properties of polymers are significantly affected by relaxation processes. Recently, we reported that poly(diethyl fumarate) (PDEF) shows two thermal anomalies on DSC measurement, despite the fact that it is a homopolymer. We attribute these two relaxations α relaxation and β relaxation, respectively. In this study, we investigate the two relaxations of fumarate-containing polymers by DSC, solid-state NMR, and X-ray scattering. The two relaxations are present even in a copolymer of diethyl fumarate and ethyl acrylate with fumarate segments of 30%. We used poly(methyl methacrylate) (PMMA) as a model polymer for comparison, since there are detailed investigations of its dynamics and physical properties. Solid-state NMR indicates that the very local relaxation of poly(fumarate)s is not significantly different from that of PMMA. The tensile test showed that PDEF is still brittle at above β relaxation temperature and below α relaxation temperature. It was revealed that a structural anisotropy appeared when PDEF was extended at around α relaxation temperature. We discuss the effect of the glassy packing of the rigid polymer chain including the DEF segments on the strong β relaxation behavior. Our data provide insight into the microscopic mechanism of β relaxation of vinyl polymers.

ASD Formation Prior to Material Characterization as Key Parameter for Accurate Measurements and Subsequent Process Simulation for Hot-Melt Extrusion

Process simulation facilitates scale-up of hot-melt extrusion (HME) and enhances proper understanding of the underlying critical process parameters. However, performing numeric simulations requires profound knowledge of the employed materials’ properties. For example, an accurate description of the compounds’ melt rheology is paramount for proper simulations. Hence, sample preparation needs to be optimized to yield results as predictive as possible. To identify the optimal preparation method for small amplitude oscillatory shear (SAOS) rheological measurements, binary mixtures of hydroxypropylmethylcellulose acetate succinate or methacrylic acid ethyl acrylate copolymer (Eudragit L100-55) together with the model drugs celecoxib and ketoconazole were prepared. The physical powder mixtures were introduced into the SAOS as a compressed tablet or a disk prepared via vacuum compression molding (VCM). Simulations with the derived parameters were conducted and compared to lab-scale extrusion trials. VCM was identified as the ideal preparation method resulting in the highest similarity between simulated and experimental values, while simulation based on conventional powder-based methods insufficiently described the HME process.

The effect of molecular structure on the properties of cationic polyacrylate and its flocculation‐flotation performance of oilfield oily wastewater treatment

AbstractWith the increasing amount of oily wastewater produced in the offshore oilfield, more efficient air flotation agent is needed to be developed. Cationic polyacrylate with amphiphilic structure has been found to be a type of potential efficient air flotation agent. However, the effect of molecular structure on its properties and performance was lack of research. In this paper, copolymers with tertiary amine as side group were synthesized by copolymerization of ethyl acrylate (EA) and tertiary amine monomers, and then a series of cationic polyacrylates were prepared by quaternization of tertiary amine with quaternization reagent. The effects of tertiary amine monomer type (including dimethylaminopropyl methacrylamide (DPM) and dimethylaminoethyl methacrylate (DEM)), quaternization reagent type (including 3‐Chloro‐1,2‐Propanediol and 3‐chloro‐2‐hydroxytrimethylammonium chloride) and quaternization degree on the cationic polyacrylate properties and its flotation performance were investigated. The experimental results showed that the flotation performance increased with the increasing hydrophilicity and cation degree of the hydrophilic unit in the cationic polyacrylate. When the tertiary amine monomer was DPM, quaternization reagent was 3‐chloro‐2‐hydroxytrimethylammonium chloride, and theoretical quaternization degree was 100%, the oil removal of product PE‐M‐1.0 was the highest. When PE‐M‐1.0 dosage was 50 mg/L, gas flow was 1 L/min, flotation time was 10 min, its oil removal rate was higher than 95% in the range of 20‑60°C. The results of zeta potential measurement and microfluidic experiment showed that PE‐M‐1.0 can increase the size of oil droplets by destroying the electric double layer on the surface of oil droplets and maintain the stability of bubbles, which was helpful for the improve of gas bubble‐oil droplet collision probability and adhesion efficiency.

Development of Enteric-coated Tablets of Sodium 4,4'-(propnadiamido)dibenzoate

Introduction. Enteric coat have a wide range of functions: from protecting the API from the adverse effects of the acidic environment of the stomach to targeted delivery to certain parts of the intestine in order to increase the effectiveness of the drug. When developing such dosage forms, special attention is paid to the type of film-forming polymer in the coating composition, its solubility and ability to withstand passage through the stomach. Aim. Development of enteric-coated tablets based on sodium 4,4'-(prpoandiamido)dibenzoate. Materials and methods. The objects of the study were sodium 4,4'-(propanediamido)dibenzoate 60 mg core tablets and compositions for enteric coatings. The uniformity of distribution of coatings over tablets was determined by the method developed at the Department of Technology of Medicinal Forms of SPCPU on the basis of the Fokker–Planck equation. The dissolution kinetics of enteric-coated tablets was studied using an Erweka DT 626 tablet dissolution tester ( ERWEKA GmbH , Germany). The amount of the substance that passed into the dissolution medium was determined using an SF-2000 spectrophotometer (LLC "OKB Spektr", Russia). Results and discussion. It has been established that all the studied coatings are evenly distributed over the tablets. When studying the kinetics of tablet dissolution, it was found that all coatings are resistant to acidic environments (0.1 M hydrochloric acid solution), however, in a phosphate buffer solution, the highest rate of release of the substance from tablets is achieved using a coating based on a copolymer of methacrylic acid and ethyl acrylate of the type B. Conclusion . Tablets based on sodium 4,4'-(propanediamido)dibenzoate, enteric-coated AquaPolish® P white 712.06E were developed.

A fast-healing and high-performance metallosupramolecular elastomer based on pyridine-Cu coordination

Elastomers easily undergo a catastrophic failure as soon as a crack is introduced by mechanical damage. Thus, it is extremely important for elastomers to possess fast healing ability, which enables the quick reparation of cracks. However, developing elastomers with fast self-healing ability and high mechanical strength is highly challenging. Herein, we fabricate a metallosupramolecular elastomer by facilely introducing pyridine-Cu coordination into a copolymer of ethyl acrylate and vinyl pyridine. Interestingly, the pyridine-Cu coordination has a strong photothermal effect, which readily increases the sample temperature to 60°C in 30 s under near-infrared light. At this temperature, the sticky reptation modes are activated and thus serve as the driving force for network reorganization and fast self-healing of the metallosupramolecular elastomer. Albeit with a tensile strength of 10 MPa, the scratched and completely fractured samples can be healed within 2 min and 3 h, respectively. Moreover, during the damage and healing processes, the break and reformation of the coordination bonds can be tracked through laser confocal micro-Raman spectroscopy. This provides a microscopic methodology to monitor the bond-level healing kinetics of metallosupramolecular polymers.

Development, Characterization, Optimization, and In Vivo Evaluation of Methacrylic Acid-Ethyl Acrylate Copolymer Nanoparticles Loaded with Glibenclamide in Diabetic Rats for Oral Administration.

The methacrylic acid–ethyl acrylate copolymer nanoparticles were prepared using the solvent displacement method. The independent variables were the drug/polymer ratio, surfactant concentration, Polioxyl 40 hydrogenated castor oil, the added water volume, time, and stirring speed, while size, PDI, zeta potential, and encapsulation efficiency were the response variables analyzed. A design of screening experiments was carried out to subsequently perform the optimization of the nanoparticle preparation process. The optimal formulation was characterized through the dependent variables size, PDI, zeta potential, encapsulation efficiency and drug release profiles. In vivo tests were performed in Wistar rats previously induced with diabetes by administration of streptozotocin. Once hyperglycemia was determined in rats, a suspension of nanoparticles loaded with glibenclamide was administered to them while the other group was administered with tablets of glibenclamide. The optimal nanoparticle formulation obtained a size of 18.98 +/− 9.14 nm with a PDI of 0.37085 +/− 0.014 and a zeta potential of −13.7125 +/− 1.82 mV; the encapsulation efficiency was of 44.5%. The in vivo model demonstrated a significant effect (p < 0.05) between the group administered with nanoparticles loaded with glibenclamide and the group administered with tablets compared to the group of untreated individuals.

Effect of Ethylene-Ethyl Acrylate Copolymer on the Rheological Properties of LDPE/PLST Blends

The rheological properties of polyethylene/starch blends compatibilized with ethylene–ethyl acrylate copolymer (EEA) were investigated at different temperatures and shear rates. According to the Fourier transform infrared spectroscopy (FT-IR) data, the application of EEA as a compatibilizer did not lead to the significant change in the blends’ band spectra because the concentration of acrylate groups (and consequently that of carbonyl groups) in the blends was low and the degree of hydrogen bonding was small enough. The rheological properties of blends showed that the melts of the blends were pseudoplastic materials. Viscosity of melt for all blends increased with an increase in both EEA and starch content. Power law index measurements showed that the n value increased and was less than one and the K value decreased with the increase in EEA content. Blends with higher content of starch had the lowest value of activation energy (Ea) and the sensitivity of blends to temperature decreased with an increase in starch content.

Internal plasticization of poly(vinyl chloride) by grafting acrylate copolymers via copper‐mediated atom transfer radical polymerization

AbstractInternal plasticization of poly(vinyl chloride) (PVC) was achieved in one‐step using copper‐mediated atom transfer radical polymerization to graft different ratios of random n‐butyl acrylate and 2–2‐(2‐ethoxyethoxy)ethyl acrylate copolymers from defect sites on the PVC chain. Five graft polymers were made with different ratios of poly(butyl acrylate) (PBA) and poly(2–2‐(2‐ethoxyethoxy)ethyl acrylate) (P2EEA); the glass transition temperatures (Tg) of functionalized PVC polymers range from − 25 to − 50°C. Single Tg values were observed for all polymers, indicating good compatibility between PVC and grafted chains, with no evidence of microphase separation. Plasticization efficiency is higher for polyether P2EEA moieties compared with PBA components. The resultant PVC graft copolymers are thermally more stable compared to unmodified PVC. Increasing the reaction scale from 2 to 14 g produces consistent and reproducible results, suggesting this method could be applicable on an industrial scale.

Influence of Particle Size and Drug Load on Amorphous Solid Dispersions Containing pH-Dependent Soluble Polymers and the Weak Base Ketoconazole

Among the great number of poorly soluble drugs in pharmaceutical development, most of them are weak bases. Typically, they readily dissolve in an acidic environment but are prone to precipitation at elevated pH. This was aimed to be counteracted by the preparation of amorphous solid dispersions (ASDs) using the pH-dependent soluble polymers methacrylic acid ethylacrylate copolymer (Eudragit L100–55) and hydroxypropylmethylcellulose acetate succinate (HPMCAS) via hot-melt extrusion. The hot-melt extruded ASDs were of amorphous nature and single phased with the presence of specific interactions between drug and polymer as revealed by X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FT-IR). The ASDs were milled and classified into six particle size fractions. We investigated the influence of particle size, drug load, and polymer type on the dissolution performance. The best dissolution performance was achieved for the ASD made from Eudragit L100–55 at a drug load of 10%, whereby the dissolution rate was inversely proportional to the particle size. Within a pH-shift dissolution experiment (from pH 1 to pH 6.8), amorphous-amorphous phase separation occurred as a result of exposure to acidic medium which caused markedly reduced dissolution rates at subsequent higher pH values. Phase separation could be prevented by using enteric capsules (Vcaps Enteric®), which provided optimal dissolution profiles for the Eudragit L100–55 ASD at a drug load of 10%.

Dynamic Nanocellulose Networks for Thermoset-like yet Recyclable Plastics with a High Melt Stiffness and Creep Resistance.

Many polymers, including polyethylene, feature a relatively low melting point and hence must be cross-linked to make them viable for applications that demand a high stiffness and creep resistance at elevated temperatures. The resulting thermoset plastics cannot be recycled, and therefore alternative materials with a reconfigurable internal network structure are in high demand. Here, we establish that such a thermoset-like yet recyclable material can be realized through the addition of a nanocellulose reinforcing agent. A network consisting of cellulose nanocrystals, nano- or microfibrils imparts many of the characteristics that are usually achieved through chemical cross-linking. For instance, the addition of only 7.5 wt % of either nanocellulose material significantly enhances the melt stiffness of an otherwise molten ethylene-acrylate copolymer by at least 1 order of magnitude. At the same time, the nanocellulose network reduces the melt creep elongation to less than 10%, whereas the neat molten matrix would rupture. At high shear rates, however, the molten composites do not display a significantly higher viscosity than the copolymer matrix, and therefore retain the processability of a thermoplastic material. Repeated re-extrusion at 140 °C does not compromise the thermomechanical properties, which indicates a high degree of recyclability. The versatility of dynamic nanocellulose networks is illustrated by 3D printing of a cellulose composite, where the high melt stiffness improves the printability of the resin.

Amorphous solid dispersions of weak bases with pH-dependent soluble polymers to overcome limited bioavailability due to gastric pH variability – An in-vitro approach

Several drugs are pH-dependent soluble weak bases with a poor solubility in the intestinal pH range. Additionally a variable gastric pH, which is a common issue in the population, potentially reduces the in-vivo performance due to reduced solubility at elevated pH. Aiming to avoid the influence of variable gastric pH on the dissolution performance, enteric polymers – hydroxypropylmethylcellulose acetate succinate (HPMCAS), hydroxypropylmethylcellulose phthalate (HP-55, HP-50) and methacrylic acid ethylacrylate copolymer (Eudragit L100-55) together with nevirapine as model drug were used for the preparation of solid dispersions by hot-melt extrusion. We were able to generate solid dispersions without crystalline residuals. The resulting solid dispersions were further tested for stability and dissolution performance applying two different pH-shift experiments (non-sink conditions), to simulate standard and altered gastric conditions. Solid dispersions made of enteric polymers were independent to gastric pH variability and exhibited superior dissolution performances compared to their respective physical mixtures and neat nevirapine.

In situ co-amorphisation in coated tablets – The combination of carvedilol with aspartic acid during immersion in an acidic medium

In the present study the feasibility of an in situ co-amorphisation of the basic drug carvedilol with the acidic co-former aspartic acid was investigated by immersion of film-coated tablets consisting of the two compounds in 0.1 MHCl. Tablets containing either crystalline carvedilol with aspartic acid or only crystalline carvedilol were prepared and coated with a gastro-resistant but water-permeable coating of a methacrylic acid – ethyl acrylate copolymer (Eudragit®L55). The film-coated tablets were immersed in 0.1 M HCl for 0, 45, and 120 min and their solid-state properties were analysed by X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and Fourier transformed infrared spectroscopy (FTIR). The drug release behaviour from these tablets was investigated at pH 6.8. It was shown that the formulation containing carvedilol with aspartic acid formed a co-amorphous system during immersion, while the formulation containing only carvedilol remained crystalline. FTIR spectroscopy indicated molecular interactions in the co-amorphous carvedilol-aspartic acid system, which explained the single Tg found using DMA (106 ± 4 °C). However, because of a lack of sufficient disintegration, drug release of the immersed co-amorphous formulation was lower than from the untreated tablets (immersed for 0 min) containing only carvedilol or the crystalline physical mixture of carvedilol and aspartic acid. After overcoming the disadvantage of the insufficient disintegration, it may be concluded that in situ co-amorphisation in a film-coated tablet by immersion in 0.1 M HCl appears to be a feasible formulation approach for poorly water-soluble basic drugs.