To analyze and compare several commercially available acrylic intraocular lenses (IOLs) with particular regard to their clinical significance, we examined the physicochemical and surface properties of four currently available acrylic IOLs using static water contact angle, atomic force microscopy (AFM), Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. The hydrophobic acrylic IOLs, ZA9003, and MA60BM, had contact angles ranging from 77.9° ± 0.65° to 84.4° ± 0.09°. The contact angles in the hydrophilic acrylic (970C) and heparin-surface-modified (HSM) hydrophilic acrylic IOLs (BioVue) were 61.8° ± 0.45° and 69.7° ± 0.76°, respectively. The roughness of the IOL optic surface differed depending on the type of IOL (p < 0.001). The surface roughness of BioVue had the lowest value: 5.87 ± 1.26 nm. This suggests that the BioVue IOL may lead to reduced cellular adhesion compared to the unmodified IOLs. All IOLs including those composed of acrylic optic materials from different manufacturers showed distinct Raman spectra peaks. The glass transition temperatures (T_g) for the hydrophobic acrylic IOLs were between 12.5 and 13.8 °C. These results suggest that the intraoperative and postoperative behavior of an IOL can be predicted. This information is also expected to contribute greatly to the industrial production of reliable biocompatible IOLs.

Biochar has attracted considerable attention in numerous industrial and environmental applications because of its advantageous properties. Pyrolysis, a cost-effective and eco-friendly engineering technique for improving biochar’s physicochemical and adsorption properties, is important in a variety of environmental applications. The effect of pyrolysis temperature and ball-milling time on the physicochemical properties of biochar derived from rice bran was investigated in this study, and its effectiveness in the aqueous removal of rhodamine B (RhB) dye was evaluated. The biochar was prepared by pyrolyzing rice bran at various temperatures, i.e., 400, 500, 600, and 700 ℃ (RB 400, RB 500, RB 600, and RB 700, respectively). In addition, in order to investigate the effect of the ball-milling time on the RB 600 biochar, it was milled for 30, 60, 120, 180, and 240 min. The surfaces of the raw material and biochar exhibited honeycomb-like pores and a layered structure. The biochar structure shrank, became fragile, and cracked as the pyrolysis temperature increased. After ball milling, the honeycomb-like pores and layered structure of the pristine biochar were transformed into irregular particles. The particle size decreased as milling time increased. Furthermore, the physicochemical properties of ball-milled biochar were superior to those of pristine biochar. According to the Raman spectral analysis, the I_D/I_G ratio decreased as the pyrolysis temperature and the milling time increased, indicating a decreased disorder and an increased graphitization in the biochar. The efficiency of RhB removal increased as the pyrolysis temperature and ball-milling time increased, and up to 82% of RhB was removed from 50 mg of biochar milled for 180 min at 600 °C.

Cerebral ischemic stroke is one of the most common neurodegenerative conditions characterized by cerebral infarction, death of the brain tissue, and loss of brain function. Cerebral ischemia-reperfusion injury is the tissue damage caused when blood supply begins to the tissue after a period of ischemia or poor oxygen supply. In this study, we preliminarily investigated the biochemical changes in the brain hippocampal area, CA1, resulting from ischemia reperfusion and neuronal nitric oxide synthase (nNOS) inhibitor treatment in rats using Raman spectroscopy. A drastic spectral change was observed in the ischemia-reperfusion brain tissue; a strong dependency between the intensity of certain Raman bands was observed at the amide positions of 1276 and 1658 cm ⁻¹ and at the lipid positions of 1300 and 1438 cm ⁻¹ . The spectrum of nNOS inhibitor-treated brain tissue was similar to that of the normal brain tissue, indicating that the nNOS inhibitor could protect the brain against excessive production of NO and biochemical processes dependent on it. Principal component analysis (PCA) precisely identified three classes of tissues: normal; ischemic; and nNOS inhibitor-treated. Therefore, we suggest that quantitative analysis of the changes in the brain tissue by using Raman spectroscopy with multivariate statistical technique could be effective for evaluating neuronal injury and drug effects.

Exosomes are potential biomarkers for disease diagnosis and treatment, as well as drug carriers. However, as their isolation and detection remain critical issues, convenient, rapid, low-cost, and effective methods are necessary. In this study, we present a rapid and simple method for directly capturing and analyzing exosomes from complex cell culture media using CaTiO₃:Eu³⁺@Fe₃O₄ multifunctional nanocomposites. The CaTiO₃:Eu³⁺@Fe₃O₄ nanocomposites were prepared by high-energy ball-milling and used to isolate exosomes by binding CaTiO₃:Eu³⁺@Fe₃O₄ nanocomposites and the hydrophilic phosphate head of the exosome phospholipids. Notably, the developed CaTiO₃:Eu³⁺@Fe₃O₄ multifunctional nanocomposites achieved results comparable with those of commercially available TiO₂ and were separated using a magnet within 10 min. Moreover, we report a surface-enhanced Raman scattering (SERS)-based immunoassay for detecting the exosome biomarker CD81. Gold nanorods (Au NRs) were modified with detection antibodies, and antibody-conjugated Au NRs were labeled with 3, 3, diethylthiatricarbocyanine iodide (DTTC) as the SERS tags. A method combining magnetic separation and SERS was developed to detect exosomal biomarker CD81. The results of this study demonstrate the feasibility of this new technique as a useful tool for exosome isolation and detection.

We demonstrate a flexible, low-cost, and highly reproducible hydrophobic surface-enhanced Raman scattering (SERS) substrate produced by inkjet printing sil