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A superhydrophobic coating composed of epoxy on the bottom and siloxane-modified silica on the top was prepared by employing the scraping and spraying methods. The superhydrophobic coating possesses excellent mechanical properties, is superhydrophobic (water contact angle, WCA = 164.3°), and has low adhesion. The long-term corrosion resistance of the epoxy coating and the superhydrophobic coating in a 3.5 % NaCl solution and hydrogen sulfide environment was assessed using electrochemical impedance spectroscopy (EIS), polarization curve analysis, immersion testing, and X-ray diffraction (XRD). Test results indicate that the superhydrophobic coating has excellent anti-corrosion capability in an H 2 S environment for 50 days and in a 3.5 % NaCl solution for 60 days. This is of great significance for developing the potential applications of superhydrophobic coatings in H 2 S environments. [Display omitted] • Epoxy resin and superhydrophobic surface combination for carbon steel substrate protection. • The coating showed anticorrosive effect in 3.5 % sodium chloride solution. • Superhydrophobic surface has excellent corrosion resistance in H 2 S environment of alternating temperatures and humidities. [ABSTRACT FROM AUTHOR]

Low-cost and scalable fabrication processes are needed to prepare efficient superhydrophobic materials, particularly for oil/water separation and metal protection against severe oil spills and metal corrosion. Here, an effective oil/water separation mesh with long-lasting acid/base durability and corrosive resistance is reported. In this work, the mesh was fabricated by simply spraying nano soil particles cross-linked with melamine resin and impregnating them with polyethylene (PE) solution. The multi-layered morphology obtained from the spraying and impregnating process which provides the unique wetting properties for the stainless steel (SS) mesh, such as superhydrophobicity and low water adhesion. Also the low chemical activity of alkyl sp3 carbon-hydrogen bonds provides acid/base resistance for the manufactured material. By utilizing these unique properties, not only can gravity-driven efficient oil/corrosive fluid separation be achieved, but the fabricated superhydrophobic stainless steel (SSS) mesh retains high separation efficiency (> 99%) and superhydrophobicity (water contact angle, WCA > 150°) in reuse process of wastewater in treated oil. More importantly, this excellent protection can effectively reduce the corrosion rate of the mesh by more than two orders of magnitude (SS mesh i corr 1.82 × 10−8 A·cm−2; SSS mesh i corr 9.84 × 10−11 A·cm−2) which providing a long-lasting protection even after 16 days of immersion in 3.5 wt% NaCl solution. All in all, the easy operation, acid/base resistance, high separation efficiency, and corrosion inhibition efficiency of the SSS mesh give them great potential for oil/water separation and metal protection applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to low ability to pass through the cell membrane and lack of proof in target delivery in vivo , anti-microRNA oligonucleotide (AMO) has poor target ability to microRNA in the cytoplasm, which results in low AMO targeting efficiency and limits AMO success in vivo application. In this study, AMO-phospholipids conjugates were developed to provide the characteristics of the two phospholipids to self-assemble via hydrophilic AMO and hydrophobic phospholipid tails to overcome the AMO backbone structures and enhance the AMO delivery efficiency. This AMO-phospholipids enveloped nanoparticles was radiolabeled with technetium-99 m (99mTc) for cellular delivery and in vivo imaging. 99mTc-radiolabeled miR-155 targeted AMO with partial 2′-O-methyl (2′-OMe) and phosphorothioate (PS) chemical modification was prepared via the conjugation to N-hydroxysuccinimide derivative of S-acetylmercaptoacetyltriglycine (NHS-MAG3). This radiolabeled AMO is chemically conjugated with phospholipids to form AMO-phospholipid. The AMO-phospholipids served as a component of nanoparticles to embed the hydrophobic part. AMO-phospholipids fused with polycarboxybetaine (PCB) based distearoyl phosphoethanolamine-polycarboxybetaine (DSPE-PCB) modified cationic lipids to form AMO-phospholipid-coated nanoparticles (AMO-NP), which delivered AMO into cytoplasm in vitro and into tumor in vivo. Further, this radiolabeled AMO-NP was confirmed by gel electrophoresis and evaluated for its serum stability, cytotoxicity, inhibitory ability and cellular uptake in HeLa cells, as well as the fluorescent distribution in vitro. Moreover, its distribution and in vivo imaging were performed HeLa tumor-bearing mice after the injection of radiolabeled AMO-NP. The gel electrophoresis of 99mTc labeled AMO-NP showed good conjugation between AMO and 99mTc. It also kept highly stable in human serum. Western blotting results showed that AMO-NP could up-regulate the expression of C/EBPβ protein, one of target proteins of miR-155 in HeLa cells, proving the ability in the specific binding and inhibition. The cellular uptake of 99mTc labeled AMO-NP was significantly higher than that of bare AMO. Furthermore, FAM labeled AMO-NP displayed its ability of specific and effective distribution in tumor cells and a good stability in cellular level. After the system administration, the distribution and in vivo imaging results revealed the significant difference between 99mTc labeled AMO-NP and negative control probe in HeLa tumor xenograft models, which suggested the specific binding and effective delivery ability of 99Tc labeled AMO-NP in vivo. This study supports the effectiveness and efficiency of cellular and in vivo delivery of 99mTc radiolabeled AMO-NP in cervical tumor and suggests a prospective candidate for future tumor imaging. [Display omitted] [ABSTRACT FROM AUTHOR]

We developed a novel anti-vascular endothelial growth factor (VEGF) single-chain variable fragment (scFv) and evaluated its anti-inflammatory and anti-corneal neovascularization (CoNV) effects in the alkali burn model. VEGF-scFv was prepared from the derived sequence of bevacizumab with a glycine and serine repetitive linker. After being evaluated using surface plasmon resonance (SPR), enzyme-linked immunosorbent assay (ELISA), and cellular fluorescent staining, VEGF-scFv showed high specificity and good affinity with VEGF antigen and HUVEC cells. The K D value was 3.07 ± 0.37 nM and the B max value was 0.23 ± 0.01 pmol (n = 3). The corneal alkali burn model was built on male Sprague Dawley (SD) rats. ScFv was injected subconjunctivally immediately after the alkali burn. On 1, 3, 7, and 14 d after alkali burn, the area of CoNV in the VEGF-scFv group was similar to that of the dexamethasone group (2 mg/mL) and significantly smaller than the 0.9% NaCl and the bevacizumab control groups (2 mg/mL). Especially on 14 d, the CoNV area was 45.15% ± 8.46% in the VEGF-scFv group. Hematoxylin and eosin staining (HE) confirmed that few new blood vessels in the VEGF-scFv group. Both immunofluorescence staining and western blotting verified that the expression levels of VEGF, vascular endothelial growth factor receptor 2 (VEGFR2), and signal transducer and activator of transcription 3 (STAT3) in the burned corneal tissue in VEGF-scFv group were significantly lower than other groups (P < 0.05), suggesting this scFv inhibited CoNV by regulating the VEGF/VEGFR2/STAT3 pathway. Therefore, our study prepared an anti-VEGF scFv which may provide a potential treatment for corneal alkali burn for future clinical application. [Display omitted] [ABSTRACT FROM AUTHOR]

Aptamers are small molecule DNA or RNA fragments that fold into well-defined 3D structures with high specificity and affinity towards target molecules, therefore emerging as a new class of probes for radiopharmaceutical applications. In this study, a technetium‐99m (99mTc) radiolabeled nucleolin-targeted aptamer AS1411 was developed for identifying glioma in murine models. A six-carbon amine group was linked at the 5′ end of AS1411 by DNA synthesis. Following the conjugation to NHS-MAG 3 , AS1411 was radiolabeled with 99mTc. Radiochemical purity and stability were evaluated by radio-TLC and gel electrophoresis. Cellular uptake and MTT assays were carried out in the nucleon-overexpressed U87 cell line to assess the biological ability of AS1411 after conjugating with FITC or radiolabeling with 99mTc. In vivo imaging of 99mTc-AS1411 was performed in glioma tumor xenografts and 99mTc and a 99mTc-labeled non-specific negative control (NC) nucleotide were used as control groups. Biodistribution studies were performed at the terminal time point of SPECT imaging. AS1411 was successfully labeled with 99mTc with the labeling yields of 81.5% ± 3.6% (n = 5) and was verified by gel electrophoresis and gel imaging. 99mTc-AS1411 was proved to be stable in fresh human serum at room temperature for 12 h. In U87 cells, 99mTc-AS1411 showed significantly higher cellular uptake than 99mTc-NC and 99mTc (9.4% ± 2.1% vs 1.9% ± 0.4% and 0.9% ± 0.1%, P < 0.01, n = 3). FITC-conjugated AS1411 demonstrated more fluorescent signals in U87 cells than NC. In addition, 99mTc-AS1411 displayed similar cellular inhibitory ability with AS1411, which was measured by MTT assay. In U87 tumor-bearing mice, 99mTc-AS1411 demonstrated high radioactive accumulation, whereas 99mTc-NC and 99mTc only showed weak tumor uptake, suggesting the specific uptake of 99mTc-AS1411 in nucleolin-positive U87 tumors in vivo. Biodistribution results further verified the imaging results. The tumor uptake of 99mTc-AS1411 was significantly higher than that of 99mTc-NC (5.81 ± 1.55%ID/g vs 0.51 ± 0.16%ID/g, n = 4, P < 0.01). 99mTc-AS1411 can be successfully prepared via the conjugation of NHS-MAG 3 and be considered a promising imaging agent capable of identifying nucleolin-positive glioma tumors. [Display omitted] [ABSTRACT FROM AUTHOR]

Anti-miRNA oligonucleotide (AMO) has been used most widely to inhibit miRNA for loss-of-function studies and function as therapeutic agents. Iodine-131 (131I) radiolabeled AMO may have multiple functions for specific imaging, genetic inhibition, and radiotherapy. This study is to prepare a radioiodinated anti-miRNA-21 AMO by one-step synthesis for preliminary imaging in tumor xenografts and in vitro radiotherapy. A tyrosine was conjugated at the 3' end of AMO via a C6 linker for labeling with 131I. After the molecular mass of AMO was confirmed by mass spectrometry, AMO was labeled with 131I by the chloramine-T method with high labeling yield (95.5% ± 3.1%). By gel electrophoresis, the radioactive distribution of 131I-AMO was located exactly where was AMO, verifying the successful radiolabeling. 131I-AMO presented high stability during 24 h of incubation in fresh human serum. The cellular uptake of 131I or FAM-labeled AMO in DU145 was significantly higher than that in PC-3 cells. After i.v. administration in mice, single-photon emission tomography (SPECT) imaging showed that increased 131I-AMO was found in DU145 tumor from 4 h to 24 h gradually. H&E staining of major organs validated the biocompatibility of 131I-AMO in vivo. Furthermore, the ability of 131I-AMO to inhibit cell growth is superior to that of 131I, along with stronger apoptosis in DU145 cells than in PC-3 cells. Therefore, AMO can be labeled with 131I via one-step synthesis after tyrosine conjugation in this study. Its high labeling yield, stability, inhibitory effect, and tumor distribution provide the potential value in the targeted theranostic role. [Display omitted] [ABSTRACT FROM AUTHOR]