Addition Of Polyethylene Glycol Research Articles

The effect of sainfoin (Onobrychis viciifolia Scop.) drying temperature and pelleting on in vitro fermentation characteristics using equine faecal inocula

This study was conducted to determine the effects of drying temperature and pelleting of the tanniniferous forage legume sainfoin (Onobrychis viciifolia Scop.) on the in vitro fermentation characteristics by equine faecal inocula. The sainfoin used for the experiment was air dried on the land and oven dried at 30, 70 and 130 °C for 2.5 h. Part of the dried sainfoin samples was left as dried hay, another part was pelleted, resulting in 6 different samples. The hay and pellets were tested for particle size distribution and pellets were tested for their pellet quality in terms of hardness, durability and bulk density. The gas production technique was used to simulate fermentation and faecal samples of eight randomly selected horses were used to create four independent inocula mixtures that were examined in two subsequent gas production runs. Per inocula mixture, the hay and pellet samples were incubated in triplicate as is, or in combination with polyethylene glycol to inactivate the tannins. Cumulative gas production, a proxy for the organic matter (OM) fermentation, was measured for 72 h, whereafter fermentation fluids were sampled and analysed for volatile fatty acids (VFA) and pH. The results of the pellet quality measurements showed that the particle sizes of the sainfoin particles in the pellets were decreased by a higher drying temperature or by the pelleting process, indicating a loss of fibre physical effectiveness, a factor that may be indicative for chewing activity and hence saliva production. The gas production results showed a significant (P < 0.05) effect of drying temperature and the addition of polyethylene glycol on the cumulative gas production, the VFA production and the percentage of branched chain VFA produced. Hay dried at 130 °C had a lower (P < 0.05) gas production compared to hay dried at 30 and 70 °C, which indicates a lower OM fermentability. The addition of polyethylene glycol increased the gas and total VFA production, which indicates that tannins in sainfoin decrease the production of gas and VFA in hay pellets compared to the hay product. The pelleting process had no effect on the fermentation characteristics, but pelleting conditions strongly decreased the level of the amino acid lysine and its reactivity. The results indicate the increase in drying temperature to cause a decrease in the OM hindgut fermentation and the total and reactive lysine contents of sainfoin. The positive effects of the tannins (a higher proportion of propionic acid relative to acetic acid and a lower protein fermentation) remain, despite of technological treatments.

Reversible halochromic PLA film for naked-eye detection at the extreme base condition

ABSTRACT Exposure to extreme base conditions in indoor environments may lead to adverse health effects on living beings. Proper ventilation and real-time detection are very important upon exposure. A simple and highly sensitive reversible base sensor is successfully prepared for real-time detection of the extreme base condition of aqueous base analytes. Halochromic poly lactid acid (PLA) pH film sensor containing thymolphthalein (THY) dye and polyethylene glycol (PEG) was developed by solution casting method. To increase the effectiveness of PLA pH film capabilities as a base sensor, the impact of altering the concentration of THY and PEG substrate was explored. The interactions between PLA, THY, and PEG were observed by Fourier transform infrared (FTIR), and the intensity of color changes was measured using UV-VIS spectroscopy. It was found that the PLA pH film has a clear color response from colorless to blue at pH 11–13 with a rapid response time within a minute. The results also revealed that varying PEG content showed a significant effect on response time compared to varying the THY content. Real-time visual color changes of the PLA pH film with different THY content and PEG content on total color difference, (∆E) values over pH and time were observed. Color changes after immersion in buffer solutions with different pH values were evaluated spectrophotometrically using CIELAB color space. The results indicated that varying the PEG content in the film leads to a faster and more distinct reversible color change. This outcome can be attributed to PEG ability to augment the free volume within the PLA material and enabling PEG and the dye and become trapped between PLA chain. The addition of PEG and THY has improved the flexibility of PLA film, which enables great potential in many applications such as medical, textile, and packaging in base environments.

Green synthesis of polyvinylidene fluoride ultrafiltration membrane with upgraded hydrophilicity

The use of Cyrene™ as an alternative non-toxic solvent to produce a PVDF-based ultrafiltration membrane was investigated in this study. Polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) were used as organic additives to explore its ability to improve membrane hydrophilicity. The additives were introduced into the casting solution via phase inversion with a combined non-solvent induced phase separation (NIPS) and evaporation-induced phase separation (EIPS) technique. The prepared membranes were characterized to examine its morphology, mechanical properties, and filtration performance. The results show that the addition of PEG and PVP has proven able to improve the membrane hydrophilicity with the lowest contact angle of 76.81° achieved from the addition of PEG with concentration 3 wt%. However, the nascent membranes were not adequate enough, in terms of its mechanical properties, to undergo performance tests due to its very brittle nature. The overall results from this study demonstrate a great potential as a proposed method of utilizing Cyrene™ as a choice of green solvent to fabricate PVDF-based ultrafiltration membrane with the incorporation of PEG and PVP as organic additives.

GPP-TSAIII nanocomposite hydrogel-based photothermal ablation facilitates melanoma therapy

ABSTRACT Background Photothermal therapy (PTT) is a promising cancer treatment, but its application is limited by low photoconversion efficiency. In this study, we aimed to develop a novel graphene oxide (GO)-based nanocomposite hydrogel to improve the bioavailability of timosaponin AIII (TSAIII) while maximizing PTT efficacy and enhancing the antitumor effect. Methods GO was modified via physical cross-linking with polyvinyl alcohol. The pore structure of the gel was adjusted by repeated freeze-thawing and the addition of polyethylene glycol 2000 to obtain a nanocomposite hydrogel (GPP). The GPP loaded with TSAIII constituted a GPP-TSAIII drug delivery system, and its efficacy was evaluated by in vitro cytotoxicity, apoptosis, migration, and uptake analyses, and in vivo antitumor studies. Results The encapsulation rate of GPP-TSAIII was 66.36 ± 3.97%, with slower in vitro release and higher tumor cell uptake (6.4-fold) compared to TSAIII. GPP-TSAIII in combination with PTT showed better bioavailability and antitumor effects in vivo than did TSAIII, with a 1.9-fold higher tumor suppression rate than the TSAIII group. Conclusions GPP is a potential vehicle for delivery of TSAIII-like poor water-soluble anticancer drugs. The innovative PTT co-delivery system may serve as a safe and effective melanoma treatment platform for further anticancer translational purposes.

Evaluation of Thermal and Rheological Properties of Phase Change Material-Incorporated Asphalt Mastic with Porous Fillers

Incorporating phase change material (PCM) into paving materials can regulate the pavement temperature, improve the pavement durability, and mitigate the heat-island effects. In this research, porous fillers were used as the PCM carrier, and the thermal and rheological behaviors of the asphalt mastic with the PCM were evaluated. Two different carrier materials (diatomite and expanded perlite) and four types of PCMs were used in the study. The candidate filler, PCM, and proper blending ratios were determined based on the results of scanning electron microscope image analysis, the filter paper test, and the temperature sweep test. The thermal and rheological behaviors of the mastics with PCMs were further evaluated with different filler replacement ratios. Thermal analysis through a differential scanning calorimetry test, thermal conductivity and volumetric heat capacity test, and real-time temperature performance test were performed on the asphalt mastics. Rheological tests, including the complex shear modulus test, the bending beam rheometer test, and the linear amplitude sweep test, were also conducted. The modified mastics were found to have high heat capacity with the latent heat storage ability. The rheological analyses showed that with the addition of polyethylene glycol, while the low-temperature performance of the asphalt mastics was improved, the performance at intermediate and high temperatures was not adversely affected by the PCM.

Polylactic acid biocomposites with high loadings of melt-flowable organosolv lignin

Polylactic acid (PLA) was blended with a new type of organosolv lignin, called Bioleum (BL) using a melt extrusion method to obtain biocomposites with BL loadings as high as 40 wt%. Two plasticizers, namely polyethylene glycol (PEG) and triethyl citrate (TEC) were also introduced to the material system. Gel permeation chromatography, rheological analysis, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy and tensile testing were performed to characterize the biocomposites. The results revealed that BL exhibits a melt-flowable characteristic. The biocomposites' tensile strength was found to be higher than most of the previously reported cases. Overall, the BL domain size increased as the BL content was increased, causing a drop in the strength and ductility. Even though the addition of both PEG and TEC improved the ductility, PEG proved to significantly outperform TEC. With the introduction of 5 wt% PEG, the elongation at break of PLA_BL20 was increased >9 times, even exceeding that of the neat PLA by several folds. Consequently, PLA_BL20_PEG5 produced a toughness that is twice as the of the neat PLA. The findings suggest a great promise of BL to develop scalable and melt processable composites.

Effect of Additional Polyethylene Glycol and Citric Acid on Characteristics of NiMo/g-Al2O3 Catalyst in Light Cycle Gas Oil Hydrodesulfurisation

Sulfur is an impurity in diesel that causes low product quality and environmental pollution. Therefore, a catalyst is needed in the profound hydrodesulfurization (HDS) reaction to produce diesel fuel with low sulfur content. The catalyst synthesized in this work was NiMo/g-Al2O3 with the addition of PEG (2%, 4%, 6%) (w/w) and CA (1%, 2%, and 4%) (w/w). The catalyst was synthesized using the dry impregnation method with a metal concentration of 3% NiO and 15% MoO3. The obtained catalysts were characterized using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Surface Area Analyzer (SAA). This work acquired the best catalyst characteristics for the HDS process by adding 2% PEG and 1% CA with a concentration of 3.19% NiO and 13.98% MoO3. The surface area, pore volume, and diameter are 181.655 m2/g, 0.50 cm3/g, and 110.51 Å, respectively. The catalyst activity satisfies Euro V standards at 345 ℃ with a sulfur content of 9.55 ppm, and the sulfur conversion (HDS) is 98.75%. The density and cetane index of the obtained diesel fuel was 0.798 g/mL and 53.6, respectively. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Exploring the effect of surfactants on the interaction between laccase and bisphenol A by molecular docking, molecular dynamics, and energy calculations

Bisphenol A (BPA), an endocrine disruptor, has potential threat to human health due to its widespread use as a plasticizer in many industrial products. Laccase (Lac) can degrade BPA well and the intervention of some surfactants can further improve the degradation of BPA by Lac, but the exact details are not known. In this paper, focused on the Lac and BPA, as well as the surfactants rhamnolipid (RL) and polyethylene glycol (PEG) as research objects, we construct nine research systems by molecular docking, and study the effect of these two surfactants on the interaction of Lac-BPA at the molecular level through molecular dynamics (MD) simulation and MM-PBSA prediction. The results showed that these two surfactants aggregated and encapsulated the enzyme in different degrees during the MD simulations, which separated the surface part of the enzyme from the solvent, thereby weakening the environmental influence on Lac activity and changing the local residues conformation of Lac, leading to the reduction of polar solvation free energy and changing the binding state of Lac-BPA. RL promotes the binding of Lac-BPA primarily by influencing the free energy of polar solvents, while PEG weakens the binding free energy of Lac-BPA complex. These results explain the reason for the lower degradation rate of BPA with the addition of PEG than with the addition of RL in the same system under the appropriate conditions. Our work elucidates the mechanism of action by which two surfactants RL and PEG affect the Lac-BPA interaction which will provide a strong basis for improving the degradation of BPA by Lac at the molecular level.

Effects of Ammonium Polyphosphate and Organic Modified Montmorillonite on Flame Retardancy of Polyethylene Glycol/Wood-Flour-Based Phase Change Composites.

With the depletion of fossil fuel energy and both the slow development and low utilization rate of new eco-friendly energy, finding new ways to efficiently store energy has become a research hotspot. Presently, polyethylene glycol (PEG) is an excellent heat storage material, but it is a typical solid-liquid phase change material (PCM) with a risk of leakage during phase transition. A combination of wood flour (WF) and PEG can effectively eliminate the risk of leakage after the melting of PEG. However, WF and PEG are both flammable materials, which impedes their application. Therefore, it is of great significance to expand their application by forming composites from among PEG, supporting mediums, and flame-retardant additives. This will improve both their flame retardancy and phase change energy storage performance, and will also lead to the preparation of excellent flame-retardant phase change composite materials with solid-solid phase change characteristics. To address this issue, ammonium polyphosphate (APP), organic modified montmorillonite (OMMT), and WF were blended into PEG in specific proportions to prepare a series of PEG/WF-based composites. Both thermal cycling tests and thermogravimetric analysis results demonstrated that the as-prepared composites had good thermal reliability and chemical stability. In addition, during differential scanning calorimetry tests, the PEG/WF/8.0APP@2.0OMMT composite presented the highest melting latent heat (176.6 J/g), and its enthalpy efficiency reached more than 98.3%. The PEG/WF/8.0APP@2.0OMMT composite also exhibited superior thermal insulation performance when compared to the pure PEG/WF composite. Furthermore, the PEG/WF/8.0APP@2.0OMMT composite exhibited a significant 50% reduction in peak heat release rate as a result of the synergistic effect between OMMT and APP in the gas and condensed phases. This work offers a useful strategy for the fabrication of multifunctional phase-change material, which is expected to broaden its industrial applications.

The effect of molecular weight and chemical structure of cross-linkers on the properties of redox-responsive hyaluronic acid hydrogels

In this work, we investigated the effect of the size and the chemical structure of crosslinkers on the properties of hyaluronic acid-based hydrogels prepared via an inverse electron demand Diels-Alder reaction. Hydrogels having loose and dense networks were designed by cross-linkers with and without polyethylene glycol (PEG) spacers of different molecular weights (1000 and 4000 g/mol). The study showed that the properties of hydrogels such as swelling ratios (20–55 times), morphology, stability, mechanical strength (storage modulus in the range 175–858 Pa), and drug loading efficiency (87 % ~ 90 %) were greatly influenced by the addition of PEG and changing its molecular weight in the cross-linker. Particularly, the presence of PEG chains in redox- responsive crosslinkers increased the doxorubicin release (85 %, after 168 h) and the degradation rate (96 %, after 10 d) of hydrogels in the simulated reducing medium (10 mM DTT). The in vitro cytotoxicity experiments conducted for HEK-293 cells revealed that the formulated hydrogels were biocompatible, which could be a promising candidate for drug delivery applications.

PEG effects on excitonic properties of LH2 from Rhodobacter sphaeroides 2.4.1 in different environments

The effects of Polyethylene glycol (PEG) on B800 and B850 excitonic properties of the Light-Harvesting complex 2 (LH2) from Rhodobacter (Rba.) sphaeroides 2.4.1 in micellar solutions of detergents and phospholipid bilayers were investigated by a series of spectroscopies. Compared to the micellar solution, in the lipid bilayer, the lateral force applied on LH2 changed the excitonic structure of B850 and weakened the excitonic interaction between B800 molecules. In micelles, PEG addition causes LH2 aggregation, resulting in the enhancement of B850 excitonic coupling inter-complexes and conformational change of the bound carotenoid (Car). In liposomes, PEG addition causes ∼37 % fluorescence quenching of B850 excitons in the embedded LH2s by changing the surrounding hydration state.

Green Fabrication of Sustainable Porous Chitosan/Kaolin Composite Membranes Using Polyethylene Glycol as a Porogen: Membrane Morphology and Properties.

One of the major challenges in membrane manufacturing today is to reduce the environmental footprint by promoting biobased raw materials and limiting the use of toxic solvents. In this context, environmentally friendly chitosan/kaolin composite membranes, prepared using phase separation in water induced by a pH gradient, have been developed. Polyethylene glycol (PEG) with a molar mass ranging from 400 to 10,000 g·mol-1 was used as a pore forming agent. The addition of PEG to the dope solution strongly modified the morphology and properties of the formed membranes. These results indicated that PEG migration induced the formation of a network of channels promoting the penetration of the non-solvent during the phase separation process, resulting in an increase in porosity and the formation of a finger-like structure surmounted by a denser structure of interconnected pores of 50-70 nm in diameter. The hydrophilicity of the membrane surface increased likely related to PEG trapping in the composite matrix. Both phenomena were more marked as the PEG polymer chain was longer, resulting in a threefold improvement in filtration properties.

Binder removal from ceramic stereolithography green bodies: A neutron imaging and thermal analysis study

AbstractStereolithography of ceramics remains one of the most powerful additive manufacturing routes for the creation of intricate ceramic parts. Despite its utility as a forming tool, ceramic stereolithography requires a challenging debinding stage due to the requisite high polymeric loading. Earlier research has identified both the polymeric resin composition and debinding atmosphere to be crucial factors in improving debinding performance. Here, we use a combination of thermogravimetric analysis and neutron imaging to examine samples of different compositions printed using the same processing and exposure parameters. We quantify the influence of both polyethylene glycol addition and the use of different debinding atmospheres (argon and vacuum) on the debinding behavior of ceramic pellets. Specifically, we demonstrate a method for examining the concentration gradients that develop during thermal debinding with the aid of neutron tomography. We find that at a constant heating rate of 1°C/min up to 500°C, vacuum atmosphere appears to result in a greater number of cracks as compared to the use of argon. The vacuum atmosphere led to the development of lower concentration gradients in the samples on average. The greatest improvement resulted with the addition of polyethylene glycol to the samples. This addition led to significantly less cracking and much lower concentration gradients in samples during debinding. These results prompt us to conclude that while keeping printing and exposure parameters constant, composition modification has a more significant effect on the debinding improvement than heating atmosphere.

Effects of polyethylene glycol (PEG 6000) and bentonite clay incorporation in selected local browse-based diets on the performance of Small East African goats.

The study evaluated how binders affected the feed intake, weight gain, and feed conversion ratio of Small East African goats fed on a variety of native browse-based diets. Twenty-four growing goats with initial body weight approximately 10.5kg ± 1.3 (mean ± SE) were randomly allocated to the Acacia brevispica and Berchemia discolor with various levels of polyethylene glycol (PEG) and bentonite clay in a factorial completely randomized design. Six treatments (T1-T6) were used with four goats per treatment. The goats were allocated to individual pens with each treatment having 3 replicates. The selected local browse leaf meal was treated with PEG at a level of 25g/kg and bentonite clay at 20g/kg. The experiment lasted for 70days, consisting of a 14-day adaptation period. Average daily feedintake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were computed each week. The composition of the CP, OM, EE, NDF, ADF, TEPH, and CT varied greatly, with significant (P < 0.05)changes seen between the various experimental treatments. Diets treated with binders had higher DM Intake, daily weight gains, and total dry matter intake. Goats on diets treated with bentonite clay (T2) performed much better than the one treated with PEG (T1) although there was no statistically significant difference between the two (P > 0.05). Acacia brevispica-based diets treated with binders performed better than Berchemia discolor-based diets. All nutrients' digestibility coefficients were unaffected by the addition of polyethylene glycol 6000 or bentonite clay. It was concluded that bentonite clay as deactivation material can be adopted due to its low cost compared to PEG and its activity to absorb or bind anti-nutritive factors such as tannins in animal feeds. The addition of PEG and bentonite clay to A. brevispica- and B. discolor-based diet can be used to enhance feed utilization as a result of tannins deactivation.

Tuning Targeted Liposome Avidity to Cells via Lipid Phase Separation.

The addition of both cell-targeting moieties and polyethylene glycol (PEG) to nanoparticle (NP) drug delivery systems is a standard approach to improve the biodistribution, specificity, and uptake of therapeutic cargo. The spatial presentation of these molecules affects avidity of the NP to target cells in part through an interplay between the local ligand concentration and the steric hindrance imposed by PEG molecules. Here, we show that lipid phase separation in nanoparticles can modulate liposome avidity by changing the proximity of PEG and targeting protein molecules on a nanoparticle surface. Using lipid-anchored nickel-nitrilotriacetic acid (Ni-NTA) as a model ligand, we demonstrate that the attachment of lipid anchored Ni-NTA and PEG molecules to distinct lipid domains in nanoparticles can enhance liposome binding to cancer cells by increasing ligand clustering and reducing steric hindrance. We then use this technique to enhance the binding of RGD-modified liposomes, which can bind to integrins overexpressed on many cancer cells. These results demonstrate the potential of lipid phase separation to modulate the spatial presentation of targeting and shielding molecules on lipid nanocarriers, offering a powerful tool to enhance the efficacy of NP drug delivery systems.

Synthesis of Ni doped-TiO2 Thin Film Photocatalysts on Glass Surfaces

Thin film of TiO2 modified Ni2+ cationic (Ni doped-TiO2) thin films were synthesized from titanium tetraisopropoxide (TTIP) and Ni(NO3)2.6H2O using the combined sol-gel and dip coating method followed by calcination at 500oC for an hour. This study aims to determine the concentration of Ni2+ and the optimum number of layers for application as self-cleaning. Frontier transform infrared (FTIR) spectrophotometric analysis observed a shift in the vibration absorption peak of Ti-O towards a smaller wave number as an indication that the Ni2+ cationic have incorporated in the TiO2matrix in forming Ni-TiO2. Based on the of x-ray diffraction (XRD) it is known that Ni-TiO2 has anatase crystalline phase with a crystallite size of 149.20 nm. Diffuse reflectance ultraviolet-visible (DRSUV-Vis) spectrophotometry showed a decrease in the bandgap energy (3.2 eV to 2.22 eV). Surface morphological by scanning electron microscopy (SEM) method showed that the addition of polyethylene glycol (PEG) resulted in a more homogeneous distribution of particles than thin films without PEG. The self-cleaning activity of Ni-TiO2 was tested for surface hydrophilic properties by measuring the contact angle of water and oil droplets under visible light illumination.

Thermo-mechanical properties of composite filaments for 3D printing of fabrics

The objective of this study is to manufacture composite filaments to be used in three-dimensional (3D) printing of fabrics using fused deposition modeling (FDM) method. The primary properties of a fabric are flexibility and strength which are lacking in the available 3D printed materials. Polylactic acid (PLA), thermoplastic polyurethane (TPU) and poly(ethylene) glycol (PEG) were blended in different proportions and extruded using twin-screw extruder to obtain composite filaments. The properties of the filaments were studied using various material characterization methods such as uniaxial tensile test, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). With the addition of PEG in the PLA/TPU composition, it was found that the yield stress and Young’s modulus of the composite filaments have significantly decreased compared to that of pure PLA filament. It was also noted that there was no significant difference in ultimate tensile strength whereas the elongation at break was increased by more than 500%. Using the composite filament, a plain weave fabric structure was 3D printed to investigate the printing ability of a complex structure. It is concluded that the composite filaments developed are suitable for 3D printing but non-uniformity in diameter affects the print quality and hence the overall properties of fabrics.

Preparation and Characterization of PVDF-TiO2 Mixed-Matrix Membrane with PVP and PEG as Pore-Forming Agents for BSA Rejection.

Polymeric membranes offer straightforward modification methods that make industry scaling affordable and easy; however, these materials are hydrophobic, prone to fouling, and vulnerable to extreme operating conditions. Various attempts were made in this study to fix the challenges in using polymeric membranes and create mixed-matrix membrane (MMMs) with improved properties and hydrophilicity by adding titanium dioxide (TiO2) and pore-forming agents to hydrophobic polyvinylidene fluoride (PVDF). The PVDF mixed-matrix ultrafiltration membranes in this study were made using the non-solvent phase inversion approach which is a simple and effective method for increasing the hydrophilic nature of membranes. Polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) as pore-forming chemicals were created. Pure water flux, BSA flux, and BSA rejection were calculated to evaluate the mixed-matrix membrane's efficiency. Bovine serum albumin (BSA) solution was employed in this study to examine the protein rejection ability. Increases in hydrophilicity, viscosity, and flux in pure water and BSA solution were achieved using PVP and PEG additives. The PVDF membrane's hydrophilicity was raised with the addition of TiO2, showing an increased contact angle to 71°. The results show that the PVDF-PVP-TiO2 membrane achieved its optimum water flux of 97 L/(m2h) while the PVDF-PEG-TiO2 membrane rejected BSA at a rate greater than 97%. The findings demonstrate that use of a support or additive improved filtration performance compared to a pristine polymeric membrane by increasing its hydrophilicity.

Evaluation of shellac‐polyethylene glycol as an alternative material for fabrication of fused filament fabrication 3D printing filament at low extrusion temperature

AbstractThe lack of biopolymer filament has been recognized as a significant challenge to fused filament fabrication (FFF) or fused deposition modeling (FDM) 3D printing. According to the restricted choice, shellac is a natural polymer of interest due to its thermoplastic property at a low temperature. The purpose of this study was to evaluate the feasibility of applying shellac as a candidate biopolymer for FFF 3D printing filaments. Shellac matrices and plasticized shellac matrices of varying grades of polyethylene glycol (PEG) were prepared using hot melt processes, and their physicochemical properties and filament properties were investigated. The results showed that a shellac matrix could be easily prepared at 80°C and stayed stable for up to 12 h. The addition of PEG could improve the stability of the shellac matrix as demonstrated by a slight deviation in acid value, percent insoluble solid, and FTIR spectra after annealing for 24 h. The shellac filaments with acceptable appearance and mechanical properties were also produced at 80 ± 5°C by the incorporation of 10–20% w/w of PEG 4000 or PEG 10000. Therefore, SHL‐PEG might be a good candidate material for the fabrication of 3D printing filament, especially at low extrusion temperature.

Steric Exclusion Chromatography for Purification of Biomolecules—A Review

Steric exclusion chromatography (SXC) is a purification method that is based on steric exclusion effects from the surface of the target and a hydrophilic stationary phase after the addition of polyethylene glycol (PEG), which leads to an association of the target with the stationary phase without direct binding, such as covalent, electrostatic, and hydrophilic/hydrophobic interactions. The gentle nature of the method has led to an increased focus on sensitive targets such as enveloped viruses with potential for other sensitive entities, e.g., extracellular vesicles and virus-like particles. SXC is related to PEG-mediated protein precipitation, but investigation of further process parameters was crucial to gain a better understanding of the SXC method. After explaining mechanistic fundamentals and their discovery, this review summarizes the findings on SXC from its first reference 11 years ago until today. Different applications of SXC are presented, demonstrating that the method can be used for a wide variety of targets and achieves high recovery rates and impurity removal. Further, critical process parameters for successful process implementation are discussed, including technical requirements, buffer composition, and scalability.