Su1510

The surface and section morphologies of the dried hydrogels were investigated using the SEM technique. SEM micrographs were recorded using the HITACHI SU 1510 (Hitachi SU-1510, Hitachi Company, Tokyo, Japan) Scanning Electron Microscope. Samples were analyzed in surface or cross-sections as follows: the dry gels were cut transversally (parallel with the vertical axis of the cylinder) using a scalpel. The exposed transversal section was observed. The individual samples were fixed on an aluminum stub covered with a double adhesive carbon band. Before observation, the samples were placed on the chamber pedestal of a Cressington 108 Sputter Coater device and coated with a 7 nm thick gold layer, under vacuum.

The plant specimens were prepared as a small piece from fresh yacón leaf. The specimens were mounted using double-sided carbon tape. For LVSEM, SU-1510 (Hitachi High-Technologies, Tokyo, Japan) was used with the vacuum condition and accelerating voltage set at 30 Pa and 15 kV, respectively. The effect of DCM rinsed within a few seconds was measured both for intact (a) and treated (b) leaves (Figure 7).

A scanning electron microscope (SEM, SU1510, Hitachi High Technologies, Tokyo, Japan) was used for the observation of the morphology of PCP-1C. The dried sample powder was mounted on the sample stage with conductive double-sided tape, and gold was sprayed under vacuum conditions. Glucose was used as the standard, and the carbohydrate content was measured at 490 nm via the phenol-sulfuric acid method. With galacturonic acid as the standard, the total uronic acid content was quantitatively determined at 520 nm by the m-hydroxybiphenyl colorimetric method. With bovine serum albumin powder as the standard, the protein content was revealed to be 595 nm via the Coomassie brilliant blue method [7 (link)].

The surfaces of the control, UV, blastedHF, and blastedHF+UV specimens were first observed under a scanning electron microscope (SEM, SU1510, Hitachi High-Technologies, Tokyo, Japan) at an accelerating voltage of 15 kV after sputter coating with Au using an ion coater (QUICK COATER SC-701, Sanyu Electron, Tokyo, Japan). Both surfaces of the disks and tapered cylinders were evaluated.
Examination with an atomic force microscope (AFM; Nanosurf Easyscan 2, Nanosurf, AG, Liestal, Switzerland) revealed the three-dimensional surface morphology and surface roughness (Sa) of the surface-modified disk specimens. AFM images were captured in air. The scans were obtained in the dynamic force mode with a tapping cantilever (Tap 190 Al-G, Budget Sensors; Innovative Solutions Bulgaria Ltd., Sofia, Bulgaria). AFM images were obtained for an area of 25 × 25 µm². Surface roughness was measured as the three-dimensional arithmetic height (Sa) value obtained from the captured images on AFM analysis. Three specimens for each condition were measured.
Contact angles for each specimen with respect to double-distilled water were measured using a contact angle meter (DMe-201; Kyowa Interface Science Co. Ltd., Tokyo, Japan). The volume of the water drops was maintained at 1.0 µL, and 10 s measurements of each surface were made thrice under controlled conditions of 25 ± 1 °C and 46% humidity.

The micro-structures of the three EPSs were observed by SEM (SU1510, Hitachi High Technologies, Tokyo, Japan) [15 (link)]. After freeze-drying, the EPSs were ground in a mortar. Then, the EPSs were coated with a layer of gold powder in a carbon coater at 10 Pa vacuum. Each sample was observed with 3.5, 7.0, and 10.0 K magnification.

B. coccoides GA1 strain was washed with PBS, fixed in 2.5% glutaraldehyde buffer in 50 mM phosphate (pH 7.2), and then postfixed in 1% osmium tetroxide in 50 mM phosphate buffer (pH 7.2). Samples were dried with a critical point dryer (CPD 030; Leica Microsystems), coated with platinum, and observed under a scanning electron microscope (SU‐1510; Hitachi High‐Technologies) at 3.0 kV.