Formulation and Evaluation of Fenbendazole Extended-Release Extrudes Processed by Hot-Melt Extrusion

This study aimed to demonstrate the feasibility of hot-melt extrusion in the development of extended-release formulations of Fenbendazole (Fen) dispersed in PEO/PCL blend-based matrices. Their thermal, physical, chemical and viscosity properties were assessed by differential scanning calorimetry, thermogravimetric analysis/derivative thermogravimetry, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, and melt flow index. Drug dispersion was analyzed by scanning electron microscopy with electron dispersive X-ray spectroscopy, and drug release was evaluated by ultraviolet-visible spectroscopy. A thermal analysis indicated the conversion of the drug to its amorphous state. FTIR analysis endorsed the thermal studies pointing to a decrease in the drug’s crystallinity with the establishment of intermolecular interactions. XRD analysis confirmed the amorphous nature of Fen. MFI test revealed that PCL acts as a plasticizer when melt-processed with PEO. SEM images displayed irregular surfaces with voids and pores, while EDX spectra demonstrated a homogeneous drug distribution throughout the polymeric carrier. Dissolution testing revealed that PCL retards the drug release proportionally to the content of such polymer incorporated. These melt-extruded matrices showed that the drug release rate in a PEO/PCL blend can easily be tailored by altering the ratio of PCL to address the issues related to the multiple-dosing regimen of Fen in ruminants

Compatibility Study between Fenbendazole and Polymeric Excipients Used in Pharmaceutical Dosage Forms Using Thermal and Non-Thermal Analytical Techniques

The body of work described in this research paper evaluates the compatibility between Fenbendazole (Fen), which is a broad-spectrum anthelmintic with promising antitumor activity, and three polymeric excipients commonly applied in pharmaceutical dosage forms. The assessment of binary mixtures was performed by differential scanning calorimetry and thermogravimetric analysis/derivative thermogravimetry to predict physical and/or chemical interactions, followed by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), and high-performance liquid chromatography (HPLC) to confirm or exclude any interactions. Thermal studies suggested the presence of interactions between Fen and P 407, PCL, and PLA. To validate these data, XRD showed that Fen is compatible with PCL and PLA, suggesting some interaction with P 407. FTIR demonstrated that PCL and PLA can establish physical interactions with Fen; moreover, it suggested that P 407 interacts not only physically but also chemically, which was later proved by HPLC to be only new intermolecular interactions. This work supports the further application of P 407, PCL, and PLA for the development of new medicinal and veterinary formulations containing Fen, since they do not affect the physical and chemical characteristics of the active ingredient and consequently its bioavailability and therapeutic efficacy

Compatibility Study between Fenbendazole and Polymeric Excipients Used in Pharmaceutical Dosage Forms Using Thermal and Non-Thermal Analytical Techniques

The body of work described in this research paper evaluates the compatibility between Fenbendazole (Fen), which is a broad-spectrum anthelmintic with promising antitumor activity, and three polymeric excipients commonly applied in pharmaceutical dosage forms. The assessment of binary mixtures was performed by differential scanning calorimetry and thermogravimetric analysis/derivative thermogravimetry to predict physical and/or chemical interactions, followed by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), and high-performance liquid chromatography (HPLC) to confirm or exclude any interactions. Thermal studies suggested the presence of interactions between Fen and P 407, PCL, and PLA. To validate these data, XRD showed that Fen is compatible with PCL and PLA, suggesting some interaction with P 407. FTIR demonstrated that PCL and PLA can establish physical interactions with Fen; moreover, it suggested that P 407 interacts not only physically but also chemically, which was later proved by HPLC to be only new intermolecular interactions. This work supports the further application of P 407, PCL, and PLA for the development of new medicinal and veterinary formulations containing Fen, since they do not affect the physical and chemical characteristics of the active ingredient and consequently its bioavailability and therapeutic efficacy

Lower Critical Solution Temperature Tuning and Swelling Behaviours of NVCL-Based Hydrogels for Potential 4D Printing Applications

The phase transitions of poly (N-vinyl caprolactam) (PNVCL) hydrogels are currently under investigation as possible materials for biomedical applications thanks to their thermosensitive properties. This study aims to use the photopolymerisation process to simulate the 4D printing process. NVCL-based polymers with different thermal properties and swellability were prepared to explore the possibility of synthetic hydrogels being used for 4D printing. In this contribution, the thermal behaviours of novel photopolymerised NVCL-based hydrogels were analysed. The lower critical solution temperature (LCST) of the physically crosslinked gels was detected using differential scanning calorimetry (DSC), ultraviolet (UV) spectroscopy, and cloud point measurement. The chemical structure of the xerogels was characterised by means of Fourier transform infrared spectroscopy (FTIR). Pulsatile swelling studies indicated that the hydrogels had thermo-reversible properties. As a result, the effect of varying the macromolecular monomer concentration was apparent. The phase transition temperature is increased when different concentrations of hydrophilic monomers are incorporated. The transition temperature of the hydrogels may allow for excellent flexibility in tailoring transition for specific applications, while the swelling and deswelling behaviour of the gels is strongly temperature- and monomer feed ratio-dependent

Degradable Nanocomposites for Fused Filament Fabrication Applications

There has been a substantial increase in the use and development of plastics over the last century. However, due to ever-diminishing petroleum feedstocks and growing concern for the environment, there has been a rise in the use of eco-friendly polymers affording similar properties to that of their depleting counterparts. Poly(ε-caprolactone) is one such polymer. This present study investigates the possibility of developing a degradable nanocomposite, suitable for fused filament fabrication, utilizing hot melt extrusion technology to blend poly(ε-caprolactone), poly(ethylene) oxide and the nanoclay halloysite at loadings of two and six weight percent. The extruded blends were characterized using common polymer testing techniques. The addition of poly(ε-caprolactone) to the poly(ethylene) oxide matrix provided a plasticizing effect which was apparent with the melt flow index and melting point of the blends reducing with an increase in poly(ε-caprolactone) content. Upon reinforcing the matrix with halloysite, there was a significant improvement in mechanical properties. The addition of halloysite significantly increased Young’s modulus 11% and 25% when the loading was two and six percent respectively. Furthermore, it was also possible to produce a filament with the desired properties, diameter 1.75 mm, for fused filament fabrication, with subsequent studies required to evaluate their printability

A Development of New Material for 4D Printing and the Material Properties Comparison between the Conventional and Stereolithography Polymerised NVCL Hydrogels

The term 4D printing refers to the idea that the shape or properties of a printed object can be changed when an external stimulus is applied. In this contribution, a temperature-responsive polymer Poly (N-vinyl caprolactam) (PNVCL), which is normally prepared via radical free polymerization, was used to justify the 4D printing concept. As a result, by using a Stereolithography (SLA) 3D printer, 4D prints were successfully prepared. These prints were able to demonstrate intelligent and reversible expansion/shrinkage behaviour as the temperature increases and decreases. Additionally, in order to examine the differences in chemical structure, thermal properties, mechanical properties, and swelling behaviours of the photopolymerised and printed parts, a series of characterisation tests, including Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), goniometry, tensile test, gel fraction measurement and pulsatile swelling study were performed on this study. In conclusion, the differences between polymerisation methods are significant; despite their chemical structures and thermal properties being similar, there were significant differences with regard to tensile properties, swellability and wettability of samples. The implications of conducting this study are remarkable, not only in providing a new way of preparing NVCL, but also in demonstrating the possibility of using 4D printed NVCL for practical applications

Effect of Chemical Treatments and HDPE-g-MA on the Physical and Mechanical Behaviour of HDPE/ Natural Fibre Composites

Abstract: Many authors have reported on the use of natural fibres (raw or chemically modified) as reinforcing elements for high density polyethylene (HDPE). These materials have generated a lot of interest due to their low cost and high specific properties. In this work, HDPE and maleic anhydride (MA) compatibilised HDPE were compounded with chemically modified flax and hemp fibres using twin screw extrusion. The physical and mechanical properties of the composite were studied to investigate the effect of chemical modification of the reinforcement fibres. HDPE-g-MA was produced by grafting MA to HDPE's backbone in a twin screw extruder using a peroxide initiated reactive process. The two chemical treatments used in this study were sodium hydroxide (NaOH) and maleic anhydride (MA) treatments. A fixed fibre loading of 10 wt.% was used in all composites. Fourier Transform Infrared Spectroscopy (FTIR) was used to examine the effects of the chemical treatments on the fibres and it was found that non-cellulosic material had been removed. The mechanical properties of the composites exhibited a significant increase in tensile strength and flexural modulus, whereas a significant decrease was recorded in Impact strength when compared to the virgin HDPE. It was also observed that the addition of the compatibiliser HDPE-g-MA significantly increased the tensile strength when compared with composites containing no compatibiliser. The tensile strength of the NaOH treated fibres reinforced HDPE also showed a significant increase compared with untreated fibre reinforced HDPE composites.Melt flow index analysis indicated that the material remained melt processable following compounding with the natural fibres. Additionally, the composites did not show any significant increase in weight due to water absorption following submersion in water for seven days. Furthermore, cost analysis revealed that the use of composites is advantageous in comparison to virgin HDPE in terms of raw material costs. From this series of tests it has been shown that chemically treatment and HDPE-g-MAcan be used to increase tensile strength and Young's modulus properties of HDPE/ natural fibres composites

Synthesis and Characterisation of Hydrogels Based on Poly (N-Vinylcaprolactam) with Diethylene Glycol Diacrylate

Poly (N-vinylcaprolactam) is a polymer that is biocompatible, water-soluble, thermally sensitive, non-toxic, and nonionic. In this study, the preparation of hydrogels based on Poly (N-vinylcaprolactam) with diethylene glycol diacrylate is presented. The N-Vinylcaprolactam-based hydrogels are synthesised by using a photopolymerisation technique using diethylene glycol diacrylate as a crosslinking agent, and Diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide as a photoinitiator. The structure of the polymers is investigated via Attenuated Total Reflectance–Fourier Transform Infrared Spectroscopy. The polymers are further characterised using differential scanning calorimetry and swelling analysis. This study is conducted to determine the characteristics of P (N-vinylcaprolactam) with diethylene glycol diacrylate, including the addition of Vinylacetate or N-Vinylpyrrolidone, and to examine the effects on the phase transition. Although various methods of free-radical polymerisation have synthesised the homopolymer, this is the first study to report the synthesis of Poly (N-vinylcaprolactam) with diethylene glycol diacrylate by using free-radical photopolymerisation, using Diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide to initiate the reaction. FTIR analysis shows that the NVCL-based copolymers are successfully polymerised through UV photopolymerisation. DSC analysis indicates that increasing the concentration of crosslinker results in a decrease in the glass transition temperature. Swelling analysis displays that the lower the concentration of crosslinker present in the hydrogel, the quicker the hydrogels reach their maximum swelling ratio

Modulation of the Lower Critical Solution Temperature of Thermoresponsive Poly(<i>N</i>-vinylcaprolactam) Utilizing Hydrophilic and Hydrophobic Monomers

Four-dimensional printing is primarily based on the concept of 3D printing technology. However, it requires additional stimulus and stimulus-responsive materials. Poly-N-vinylcaprolactam is a temperature-sensitive polymer. Unique characteristics of poly-N-vinylcaprolactam -based hydrogels offer the possibility of employing them in 4D printing. The main aim of this study is to alter the phase transition temperature of poly-N-vinylcaprolactam hydrogels. This research focuses primarily on incorporating two additional monomers with poly-N-vinylcaprolactam: Vinylacetate and N-vinylpyrrolidone. This work contributes to this growing area of research by altering (increasing and decreasing) the lower critical solution temperature of N-vinylcaprolactam through photopolymerisation. Poly-N-vinylcaprolactam exhibits a lower critical solution temperature close to the physiological temperature range of 34–37 °C. The copolymers were analysed using various characterisation techniques, such as FTIR, DSC, and UV-spectrometry. The main findings show that the inclusion of N-vinylpyrrolidone into poly-N-vinylcaprolactam increased the lower critical solution temperature above the physiological temperature. By incorporating vinylacetate, the lower critical solution temperature dropped to 21 °C, allowing for potential self-assembly of 4D-printed objects at room temperature. In this case, altering the lower critical solution temperature of the material can potentially permit the transformation of the 4D-printed object at a particular temperature