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Enrofloxacin (ENR), a broad‐spectrum antibacterial drug, has extremely poor water solubility contributing to low bioavailability, which prevents drug formulation design and limits its wide application in livestock farming and aquaculture. Compared to conventional formulations of ENR, casein (Cas)‐based drug delivery system has been reported to have significant advantages in the improvement of solubility and bioavailability of drugs. In this paper, we report the preparation process of ENR‐loaded Cas nanoparticles (ENR‐Cas) using magnetic agitation without any organic agent and the optimization of the formulation. Transmission electron microscopy (TEM), dynamic light scattering (DLS), differential scanning calorimetry (DSC), powder X‐ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) were all adopted to characterize the ENR‐Cas. Results showed that the obtained ENR‐Cas were approximately spherical with a particle size of 171.6 ± 13.8 nm with a polydispersity index of 0.322 ± 0.053. In vitro release behavior of ENR‐Cas showed a sustained release profile. Additionally, in vivo study in rats displayed that the mean plasma concentration of ENR after oral administration of ENR‐Cas was significantly higher than that treated with ENR suspension. The mean residence time (MRT0–24) of ENR was enhanced by Cas nanoparticles from 9.287 ± 0.524 to 11.372 ± 1.139 hr in comparison with ENR suspension. Accordingly, the area under the curve (AUC0–24) of ENR‐Cas was 80.521 ± 6.624 μg·hr/ml, 3.8‐fold higher than that of ENR suspension (20.850 ± 1.715 μg·hr/ml). Therefore, it can be concluded that ENR‐Cas enhanced the absorption, prolonged the retention time, and improved oral bioavailability of ENR. Taken the good oral safety of Cas into consideration, ENR‐Cas should be a more promising oral preparation of ENR for clinical application., Herein, we report the preparation process of ENR‐loaded casein (Cas) nanoparticles (ENR‐Cas) without any organic agent and the optimization of the formulation. It can be concluded from the results that ENR‐Cas enhanced the absorption, prolonged the retention time, and improved oral bioavailability of ENR. Taken the good oral safety of Cas into consideration, ENR‐Cas should be a more promising preparation of ENR for clinical application.

Citrus peels, by-products in large quantity, are rich in various functional and beneficial components which have wide applications. Chemical analysis of these components in citrus peels is an important step to determine the usefulness of the by-products for further applications. In this study, we explored Raman microscopy for rapid, nondestructive, and in situ chemical mapping of multiple main functional components from citrus peels. The relative amount and distribution in different locations (flavedo, albedo, and longitudinal section) of 3 main functional components (essential oils, carotenoids, and flavonoids) in citrus peels were systematically investigated. The distribution profiles of these components were heterogeneous on the peels and varied between different species of citrus peels. Essential oil was found mainly existed in the oil glands, while carotenoids were in the complementary location. Some flavonoids were observed in the oil glands. This study showed the capability of Raman microscopy for rapid and nondestructive analysis of multiple bio-components without extraction from plants. The information obtained from this study would assist the better production and application of the functional and beneficial components from citrus by products in an effective and sustainable manner. Practical Application This study indicated the capability of Raman microscopy for rapid and nondestructive analysis of multiple bioactive components in plant tissues. The information obtained from the study would be valuable for developing effective and sustainable strategy of utilization of citrus peels for further applications.

Undeclared food allergens due to cross contamination of processing equipment is a leading cause for food product recalls. Therefore, there is a great need for developing rapid and sensitive methods to detect food allergens. In this paper, an aptamer highly specific to egg white lysozyme was coupled to dendritic silver nanoparticles in order to perform surface enhanced Raman spectroscopy (SERS). The procedure was successfully tested in water and on a stainless steel food-handling surface. The lowest detectable concentration for lysozyme was 0.5 μg/mL in water and 5 μg/mL on a stainless steel food-handling surface. Principal component analysis shows a significant change in SERS spectra when lysozyme was present, suggesting the successful capture of lysozyme by the aptamer. Quantification of lysozyme target was also shown from 0 to 6 μg/mL, that is, 0, 0.5, 2, 6 μg/mL. Overall method took less than 40 min. The developed method can be extended to detect other food allergens using specific aptamers.

Polymethoxyflavones (PMFs) belong to a unique class of flavonoids mainly found in citrus fruits. Characterization of different PMFs is important to further understand and apply these compounds as functional ingredients in food. The objective of this study is to characterize three monohydroxylated PMFs using surface-enhanced Raman spectroscopy (SERS) and to determine the role of hydroxylation in their SERS behaviors. Serial concentrations of 3′-hydroxylnobiletin (3HN), 4′-hydroxylnobiletin (4HN), and 5-hydroxylnobiletin (5HN) were incubated with silver dendrites for SERS analysis. Results demonstrated that three PMFs exhibited significantly different SERS behaviors. 5HN produced saturation peak intensity at relative low concentration (0.05 mM), while 3HN and 4HN produced saturation peak intensity at much higher concentrations (0.5 and 1 mM, respectively) according to principal component analysis. Below saturation, 5HN had the highest peak intensity, while 3HN had the lowest peak intensity. After reaching saturation, 4HN and 5HN had similar relative peak intensities that were much greater than 3HN. The HPLC analysis revealed that 36.13 ± 1.06% of 5HN, 18.40 ± 3.31% of 4HN, and 9.66 ± 0.94% of 3HN were bound to silver. Based on these results, we speculated that different positions of hydroxylation of PMFs were critical for determining spatial conformation of PMFs on binding sites, resulting in different binding affinities and saturation points, therefore their SERS behaviors. This study first reported that the position of hydroxylation in the monohydroxylated PMFs was crucial for their interactions with silver dendrites and provided valued information for further applying SERS for molecular characterization of flavonoids. Copyright © 2016 John Wiley & Sons, Ltd.

Mg–4Al–4RE (wt%, AE44) alloy is prepared by cold-chamber high-pressure die-casting (HPDC). The microstructure, thermal stability of Al–RE phases and its effect on corrosion behavior are investigated. The main strengthening phase is Al11RE3, which is thermally instable when heated at 400 °C. Some Al11RE3 would be transformed to Al2RE. The alloy in HPDC state exhibits relatively high corrosion resistance due to the Al11RE3 at grain boundaries that can act as the corrosion barrier. While after heat treatment at 400 °C for 1000 h and 5000 h, the corrosion resistance performance degrades due to the changes of morphology and distribution of Al–RE phases.

The hydrodeoxygenation (HDO) of maize oil was performed in an autoclave with Mo-based catalysts supported by different carbon materials, such as reduced graphene oxide, activated charcoal, graphite, and fullerene. Nanostructured Mo-based catalysts with different phase compositions were prepared by using the carbothermal hydrogen reduction method at temperatures ranging from 500 to 700 °C and characterized by Raman spectroscopy, N2 adsorption isotherms, SEM, TEM, XRD, X-ray photoelectron spectroscopy, and ammonia temperature-programmed desorption. The highest total hydrocarbon yield of 90.32 % was obtained on the reduced graphene oxide-supported molybdenum carbide catalyst at 700 °C. These results are subject to the complicated effect of different factors such as phase composition, defect concentration, and particle size on the catalytic behavior of the materials. Unique structures of different supports also play a significant role in the HDO reaction. On the basis of the results of comprehensive analysis of products and catalysts, an HDO mechanism was proposed. These Mo-based catalysts are a promising system to prepare high-quality diesel fuels from renewable resources.

Surface-enhanced Raman spectroscopy (SERS) is an emerging and promising technique for the chemical analysis of food. The use of metallic nanosubstrates improves the sensitivity and capacity of conventional Raman spectroscopy greatly. This paper comprehensively reviews the development and applications of SERS in the chemical analysis of food, mainly focusing on food additives and chemical contaminants. The progress of SERS development and their applications in chemical analysis of food, from detection and characterization of target analytes in simple solvents to complex food matrices, is summarized. The advantages and limitations of different SERS substrates and methodologies are discussed. As most of the current SERS research on chemical analysis of food is still in an early stage, there are still several hurdles for further advancing SERS techniques into real-world applications for complex food products. This review includes our perspectives on the future trends of the SERS technique in the field of food analysis.

Molecular interactions between dietary flavonoids and other food components play important roles in the biological fate and activities of flavonoids. Herein, surface-enhanced Raman spectroscopy (SERS) was used to study the molecular interactions between casein, a major milk protein, and three structurally closely related polymethoxyflavones (PMFs), nobiletin, 5,3′,4′-tridemethylnobiletin, and 3′,4′-didemethylnobiletin. SERS was conducted after either conjugating casein onto silver (Ag) dendrites to interact with PMFs, or conjugating PMFs onto Ag to interact with casein. Our results show distinct selectivity of PMFs in binding to Ag dendrites and casein. Hydroxyl groups on PMFs played a key role in the interactions between PMFs and casein and Ag. Methylation reaction at certain positions of PMF structures reduced the binding capacity of PMFs to both casein and Ag. This rapid and simple method can be extended to study the interactions between other flavonoids and various food components, especially useful when there are a large number of samples. Copyright © 2012 John Wiley & Sons, Ltd.

Saturated six-membered rings were constructed directly using calcium carbide as an acetylene source by one-step procedure, and functionalized cyclohexanes, 1,3,5-triaroylcyclohexanes, were efficiently synthesized by reactions of calcium carbide with aromatic or heteroaromatic aldehydes in high yield. This protocol has the advantages of using inexpensive and renewable resource, no flammable and explosive gas and no transition-metal catalysts.

An efficient method for the 2-hydroxylation of 1,3-diketones by using atmospheric oxygen as an oxidant under transition-metal-free condition is described. The protocol has the advantages of using an inexpensive and stable oxidant, producing high yields, and requiring ecofriendly conditions.

Ricin is a potential bioterrisiom agent. There is a critical need for a method that can rapidly and simply detect ricin and other bioterrisiom agents in complex food matrices such as milk. In this study, we demonstrated a rapid method that combined immunomagnetic separation (IMS) and surface-enhanced Raman spectroscopy (SERS) to detect ricin in whole milk. IMS was used to specifically capture the ricin out of the milk. Then, SERS was applied to analyze the IMS eluate mixed with silver dendrite nanosubstrates. This approach facilitated detection and quantification down to 4 μg/mL ricin in milk within 20 min, based on the results of principal component analysis and partial least squares analysis. The feasibility of using a portable Raman instrument shows great promise for on-site detection in a processing facility. Practical Application: The method described in this manuscript that combined IMS and SERS could be used for rapid detection of ricin and other protein toxins in complex food matrices such as milk within 20 min. The use of a portable Raman could facilitate the on-site detection in a processing facility.

A method for rapid detection of foreign protein contamination in complex food matrices is critically needed. Here we present a novel method that combines immunomagnetic separation (IMS) and surface-enhanced Raman scattering (SERS) to detect ovalbumin (OVA), an egg white protein, added into whole milk. IMS was used to specifically capture the OVA out of the milk. Then SERS was applied to analyze the IMS eluate using silver dendrites as the substrate. Two SERS sample preparation methods, namely solution based and substrate based, were used to prepare the IMS eluate for SERS analysis. Results show both methods were able to detect 1 µg OVA in 1 ml milk (1 part per million). Based on the results of principal component analysis and partial least-squares analysis, solution SERS was more capable of quantitative analysis, while substrate SERS was more sensitive for qualitative analysis. The total analytical time for IMS–SERS was less than 20 min, which satisfied the requirement of rapid detection in a milk processing facility. Copyright © 2011 John Wiley & Sons, Ltd.

A family of newly synthesized monomethoxy (polyethylene glycol)-poly (D,L-lactic glycolic acid)- monomethoxy(polyethylene glycol) (MeO-PEG-poly (D,L-lactic-co-glycolic acid)-PEG-OMe, PELGE) biodegradable polymers are candidates for intravenous nanoparticle drug, because of their merits of biocompatibility and blood compatibility, and their capability of escaping from the endothelium system (RES) and adsorbing proteins. In the current research, relationships between composition, cytotoxicity, and hemocompatibility of a series of blank PELGE nanoparticles were investigated. Cytotoxicity on Chang cell lines was investigated using the methyl thiazolyl tetrazolium (MTT) assay. Human and rabbit blood were used in studies of red blood cell hemolysis, whole blood clotting time, plasma recalcification profiles, and red blood cell form and appearance in whole blood. The results suggested that the molecular weight of PEG used in the synthesis of polymers influenced their characteristics. Generally, as the molecular weight of PEG increased, increased cytotoxicity and hemocompatibility were observed. The RGR (relative growth rate) of PELGE nanoparticles synthesized with PEG 550 was above 70%, while that of PELGE nanoparticles synthesized with PEG 750 and PEG 2000 was in the range of 55–105% and 36–87% respectively. For PELGE nanoparticles synthesized with PEG 550, most hemolysis values were in the range of 1–3%, while for PELGE nanoparticles synthesized with PEG 750 and PEG 2000 hemolysis values were 1–2% and below 2%, respectively. None of the nanoparticles caused changes in red blood cell form or appearance. Based on the results, 12 kinds of PELGE were chosen for further studies. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 2933–2944, 2009

MicroRNAs (miRNAs) are a class of small RNAs ( approximately 22-nt) that play an important role in the control of different cell processes by negative regulation of protein-coding genes. In the last several years, a number of miRNA profiling strategies have been used to document the miRNA expression changes during physiological and pathological processes. Aberrant expression of miRNAs has been linked to developmental defects, cancer, neurological disorders, and heart diseases. Over 540 human miRNAs have been validated to date; however, computer models suggest there may be thousands more. As bench work continue to verify in silico predictions, miRNA profiling will remain a prominent tool for identification of differential expression miRNAs in normal cellular courses and human disorders. This review focuses on current strategies for miRNA expression profiling and discusses their sensitivity and specificity, as well as advantage and disadvantage.

An efficient method for copper catalyzed synthesis of 1,3,5-triarylpentane-1,5-diones using α,β-unsaturated ketones as unique starting materials is described. The protocol offers several advantages such as simple, inexpensive reagents, mild reaction conditions and simple work-up procedure.

Aurora-A is frequently altered in epithelial malignancies. Overexpressing Aurora-A induces centrosome amplification and G2/M cell cycle progression. We have previously shown elevated level of Aurora-A in ovarian cancer and activation of telomerase by Aurora-A in human mammary and ovarian epithelia. Here we report that Aurora-A protects ovarian cancer cells from apoptosis induced by chemotherapeutic agent and activates Akt pathway in a p53-dependent manner. Ectopic expression of Aurora-A renders cells resistant to cisplatin (CDDP), etoposide and paclitaxel-induced apoptosis and stimulates Akt1 and Akt2 activity in wild-type p53 but not p53-null ovarian cancer cells. Aurora-A inhibits cytochrome C release and Bax conformational change induced by CDDP. Knockdown of Aurora-A by RNAi sensitizes cells to CDDP-induced apoptosis and decreases phospho-Akt level in wild-type p53 cells. Reintroduction of p53 decreases Akt1 and Akt2 activation and restores CDDP sensitivity in p53-null but not p53-null-Aurora-A cells. Inhibition of Akt by small molecule inhibitor, API-2, overcomes the effects of Aurora-A-on cell survival and Bax mitochondrial translocation. Taken collectively, these data indicate that Aurora-A activates Akt and induces chemoresistance in a p53-dependent manner and that inhibition of Akt may be an effective means of overcoming Aurora-A-associated chemoresistance in ovarian cancer cells expressing wild-type p53.

Surface-enhanced Raman spectroscopy (SERS) coupled with dendritic silver nanosubstrates was used in this study for rapid detection and characterization of restricted antibiotics. Dendritic silver nanosubstrates were prepared through a simple replacement reaction and stored in deionized water for months. SERS methods with near-IR excitation at 785 nm using silver nanosubstrates were evaluated for detection of three restricted antibiotics (i.e. enrofloxacin, ciprofloxacin, and chloramphenicol) prepared in standard solutions. SERS was capable of identifying and characterizing three antibiotics quickly and accurately. Silver dendrites exhibit satisfactory and consistent performance with an analytical enhancement factor of ∼104. The limit of detection and limit of quantification for antibiotics could reach the level of 20 ppb. Silver dendrites can be kept in deionized water for up to 6 months with no signs of degradation in SERS performance. These results demonstrate a great potential of using SERS coupled with silver dendrites for rapid detection, classification, and quantification of chemical contaminants. Copyright © 2009 John Wiley & Sons, Ltd.