DOI: 10.20350/digitalcsic/17958
title: Raw data regarding rheological characterization, pore size determination and distribution, printability and oil sorption and revovery tests of the materials employed in the study: “3D-Printed Alginate/BSA-Based Aerogels: Freeze-Drying Strategies for Tunable Porosity and Enhanced Oil Sorption and Chemical-free Recovery

description: [Methods for processing the data] The files contain raw data obtained through rheological measurements, pore size determination and printability tests are organized in EXCEL files to improve visualization
description: [Description of methods used for collection/generation of data] Rheological data. A rheometer, AR-G2, from TA instruments® was used to determine the rheological properties of the different biomaterial inks at 25 °C. Flow sweep experiments were performed varying the shear rate values from 0.001 s-1 to 100 s-1. The geometry used was a 25 mm parallel plate with 1000 µm gap. Viscosity flow curves (viscosity vs. shear rate) were obtained, and a mathematical model known as the Power Law equation (Eq. 1) was fitted to these curves. η "\= " K"\ " γ ˙^(n"\-"1) (1) where η is the viscosity; γ ˙ is the shear rate; and K and n are the fitting parameters. The parameter K represents the viscosity of the ink at a shear rate of 1 Pa/s. The parameter n is inversely proportional to the shear-thinning behavior of the material, and low values of n (n &lt; 1) indicate a shear thinning behavior. Oscillatory strain sweeps from 0.01 % to 200 % strain at 1.0 Hz constant frequency were carried out to define the linear viscoelastic region. Frequency sweeps experiments that ranged from 0.01 Hz to 10 Hz at 0.1 % strain were run to obtain the storage modulus values at 1.0 Hz of each biomaterial ink. Dynamic oscillatory strain cycles were run at 1.0 Hz to obtain the recovery value of each biomaterial ink's storage modulus. For these experiments, two consecutive cycles were employed. For each cycle, a 0.1 % strain deformation for 200 s followed by a 200 % strain deformation for 200 s was applied. All measurements were carried out at room temperature. Printability tests. The uniformity factor (U) was employed to assess the degree to which the filament deviated from a perfectly straight filament. Using Image J®, the outer boundary on both sides of the filament was manually measured. The obtained length was then divided by the length of a straight reference line, providing the value of U (Eq. 2). Here, U = 1 denotes a fully uniform filament, whereas values above 1 reflect deviations from uniformity. U "\= " (length"\ "of"\ "printed"\ "filament"\ ")/(length"\ "of"\ "theorical"\ "straight"\ "filament) "\ " (2) For the determination of the printability index (Pr), a square scaffold measuring 25 × 25 mm was printed in two layers, each with a height of 0.8 mm, using a zigzag infill pattern with a 5 mm distance between filling lines, resulting in internal squares measuring approximately 5 × 5 mm. The area of these squares was quantified using Image J software, and the values were used to calculate the average printability index (Pr) according to Eq. 3. Based on this index, three gelation states are identified: insufficient gelation (Pr &lt; 1), adequate gelation (Pr = 1), and excessive gelation (Pr &gt; 1). Pr "\= " π/4 x 1/C " \= " L^2/16A "\ " (3) where C represents the circularity of the enclosed area (C "\=" 4πA/L^2 ), L is the perimeter y A is the area. To quantify printing deviations, the measured dimensions (height and diameter) were compared with the corresponding CAD designs according to Eq. 4 [22]. Deviation (%)" \= " ((Measured-Designed))/Designed*100 (4) Average Pore size. The average pore size ∅"\ " , was calculated using ImageJ® software. Micrographs were calibrated using the scale bar to ensure accurate measurements, and pore dimensions were obtained by calculating the equivalent circular diameter from the measured pore area. The results were expressed as mean ± standard deviation (SD) to describe the pore size distribution. Pore size distribution. Pore size distribution was also determined by mercury intrusion porosimetry, MIP, (Poremaster, Quantachrome Instruments), combining low-pressure (up to 55 psi) and high-pressure (up to 33,000 psi) measurements to assess meso and macroporosity. Mercury was intruded into the pore system under increasing pressure, and the cumulative intruded volume was recorded to calculate throat size distribution and accessible porosity. Oil sorption, retention and recovery. For measurements of the uptake capacity, three pieces of the dry samples were fully immersed in the oil for 30 min, then carefully removed, and the excess oil was eliminated with tissue paper. The oil uptake was calculated as the average mass of oil sorbed, expressed as grams of oil per gram of dry material. 30 min was used as testing sorption time due to the equilibrium observed when doing free swelling capacity measurements (FSC) at different times. The oil sorption capacity was calculated as the mass of sorbed oil per gram of dry material (g/g). Subsequently, the oil-loaded samples were placed inside a plastic teabag and centrifuged at 1230 rpm for 3 min. The samples were then weighed again, and the oil retention capacity was determined as the mass of retained oil per gram of dry material (g/g). For reusability tests, the centrifuged samples were re-immersed in oil for an additional 30 min, and the sorption–centrifugation procedure was repeated for consecutive cycles under identical conditions. The amount of oil recovered was calculated as the difference between the oil sorbed after the 30 min immersion step and the oil retained after centrifugation. Oil recovery was expressed as a percentage relative to the initially sorbed oil. All measurements were performed in triplicate, and the reported values correspond to mean ± standard deviation.
description: [Environmental/experimental conditions] If the text does not specify it, normal conditions are assumed.
description: This dataset contains raw data obtained for the determination of rheological propesties, printability assessment, average pore size, pore size distribution, oil sorption test and oil sorption, retention and recovery tests organized in EXCEL files and employed in the study “3D-Printed Alginate/BSA-Based Aerogels: Freeze-Drying Strategies for Tunable Porosity and Enhanced Oil Sorption and Chemical-free Recovery”.
description: - Rheological propesties - Printability assesment - Average pore size - Pore size distribution - Oil sorption test - Oil sorption, retention and recovery