Sodium Periodate Oxidation Research Articles

Underwater superoleophobicity cellulose nanofibril aerogel through regioselective sulfonation for oil/water separation

Cellulose nanofiber (CNF) aerogel regioselectively modified by sodium periodate oxidation and consecutive sodium sulfite sulfonation has been fabricated. The aerogel exhibits underwater superoleophobicity (θoil>150°) characteristic for various oils, which could be used as a filter for oil/water separation. Compared with originals, the charge density of sulfonated CNF increased from −39.8mmol/kg to −325mmol/kg, which prevented the aggregation in water suspension and resulted in better dispersion morphology of nanofibers in the final aerogel after freezing-drying. Therefore, modified aerogel with a good hierarchical structure and high charge density was able to trap more water molecules onto its voids once pre-wetted, which is energetically unfavorable for the oil to replace the water molecules. As a result, the sulfonated aerogel displayed superoleophobicity characteristic underwater thus nonpolar oil phase was completely repelled while the water easily penetrated the as-prepared aerogel. The sulfonated CNF aerogel maintained high oil-water separation efficiency by simply filtration. The oil content in filtrated water was always less than 300ppm (0.03%), and kept a stable recyclability even after 20 cycles, which could be practically used as a filter for oil/water.

Thiazolidine-Masked α-Oxo Aldehyde Functionality for Peptide and Protein Modification.

α-Oxo aldehyde-based bioconjugation chemistry has been widely explored in peptide and protein modifications for various applications in biomedical research during the past decades. The generation of α-oxo aldehyde via sodium periodate oxidation is usually limited to the N-terminus of a target protein. Internal-site functionalization of proteins with the α-oxo aldehyde handle has not been achieved yet. Herein we report a novel method for site-specific peptide and protein modification using synthetically or genetically incorporated thiazolidine-protected α-oxo aldehyde. Efficient unmasking of the aldehyde was achieved by silver ion-mediated hydrolysis of thiazolidine under mild conditions for the first time. A model peptide and a recombinant protein were used to demonstrate the utility of this new method, which were site-specifically modified by oxime ligation with an oxyamine-functionalized peptide labeling reagent. Therefore, our current method has enriched the α-oxo aldehyde synthetic tool box in peptide and protein bioconjugation chemistry and holds great potential to be explored in novel applications in the future.

Preparation and identification of Jujuboside A artificial antigen

Immunogenic antigen (jujuboside A-BSA) and coating antigen (jujuboside A-OVA) of jujuboside A were synthesized by sodium periodate oxidation method for the first time. Jujuboside A artificial antigen was confirmed by matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF-MS). The titer and specificity of the antibody in serum of immunized mice were detected by enzyme-linked immunosorbent assay (ELISA). The corrected relation curve of inhibition rate showed that the antibody against Jujuboside A obtained from immunized mice could bind to jujuboside A and the titer was up to 1∶4 000. The jujuboside A artificial antigen was synthesized, which can be used further to preparation of monoclonal antibody and the pharmacokinetics study of jujuboside A in laboratory animals.

Preparation and characterization of biodegradable nano hydroxyapatite–bacterial cellulose composites with well-defined honeycomb pore arrays for bone tissue engineering applications

Bacterial cellulose (BC), a nano fibrous hydrogel synthesized from non-pathogenic bacteria, is an excellent candidate scaffold for bone tissue engineering applications due to its biocompatibility, high purity and mechanical strength. However, BC is not biodegradable and possesses small pore sizes, which hinders the ingrowth of cells and thereby limits its potential as a bone tissue engineering scaffold. In this study, microporous BC (termed Porous BC) scaffolds with well-defined honeycomb pore arrays were prepared using a laser patterning technique. The BC scaffolds were modified using periodate oxidation to yield biodegradable oxidized BC scaffolds. In a unique manner, the BC scaffolds were then mineralized with nano hydroxyapatite (nano HA) to mimic the inorganic component of native bone tissue, improve bone cell compatibility, enhance mechanical properties, and control degradation. Results confirmed that sodium periodate oxidation successfully oxidized BC and Porous BC honeycomb pore arrays with 300 μm pore sizes with irregularly shaped 77 ± 15 nm nano HA and aggregated 200–500 nm nano HA were formed. BC and its composites displayed suitable mechanical properties for bone tissue engineering applications. The in vitro degradation study showed a significant 13–25 % loss of their dry mass in the oxidized BC composites thus confirming that the oxidized cellulose can biodegrade. Most importantly, the results also demonstrated that human-derived bone marrow mesenchymal stem cells (hMSCs) adhered to and were viable on the BC and its composites, thus, confirming their potential to serve as improved bone tissue engineering scaffolds. The novelty of the present study includes the precipitation of nano HA onto cellulose to promote hMSCs functions for improving orthopedic applications.

Cross-kingdom inhibition of breast cancer growth by plant miR159.

MicroRNAs (miRNAs) are critical regulators of gene expression, and exert extensive impacts on development, physiology, and disease of eukaryotes. A high degree of parallelism is found in the molecular basis of miRNA biogenesis and action in plants and animals. Recent studies interestingly suggest a potential cross-kingdom action of plant-derived miRNAs, through dietary intake, in regulating mammalian gene expression. Although the source and scope of plant miRNAs detected in mammalian specimens remain controversial, these initial studies inspired us to determine whether plant miRNAs can be detected in Western human sera and whether these plant miRNAs are able to influence gene expression and cellular processes related to human diseases such as cancer. Here we found that Western donor sera contained the plant miRNA miR159, whose abundance in the serum was inversely correlated with breast cancer incidence and progression in patients. In human sera, miR159 was predominantly detected in the extracellular vesicles, and was resistant to sodium periodate oxidation suggesting the plant-originated 2'-O-methylation on the 3' terminal ribose. In breast cancer cells but not non-cancerous mammary epithelial cells, a synthetic mimic of miR159 was capable of inhibiting proliferation by targeting TCF7 that encodes a Wnt signaling transcription factor, leading to a decrease in MYC protein levels. Oral administration of miR159 mimic significantly suppressed the growth of xenograft breast tumors in mice. These results demonstrate for the first time that a plant miRNA can inhibit cancer growth in mammals.

Periodate oxidation of 4-O-methylglucuronoxylans: Influence of the reaction conditions

This work aims at studying the sodium periodate oxidation of 4-O-methylglucuronoxylans (MGX) in different experimental conditions for a control of the oxidation degree. A series of sodium periodate oxidation reactions were conducted at three NaIO4/xylose molar ratios: 0.05, 0.20 and 1.00. The effects of xylan molar mass, xylan concentration and reaction temperature on the reaction rate have been evaluated by UV/visible spectroscopy at 0.20 NaIO4/xylose ratio. No depolymerization is observed at 0.05 ratio while depolymerization occurs at 0.20 and is even complete at 1.00 NaIO4/xylose ratio. An increase of the reaction temperature – up to 80°C – leads to an increase of the oxidation rate with no effect on the depolymerization. At high xylan concentrations, the oxidation rate increases but promotes chains aggregation.

Spherical and rod-like dialdehyde cellulose nanocrystals by sodium periodate oxidation: Optimization with double response surface model and templates for silver nanoparticles

A novel double response surface model is used first time to optimize a regioselective process to prepare spherical di- aldehyde cellulose nanocrystals (SDACN) and rod-like dialdehyde cellulose nanocrystals (RDACN) via one-step sodium pe- riodate (NaIO4) oxidation. The influence of four preparation factors (solid-liquid ratio, NaIO4 concentration, reaction time and temperature) on the yields and aldehyde contents of the final products were evaluated. For comparison, rod-like cellulose nanocrystals (CN-M and CN-S) were prepared by hydrochloric/formic acid hydrolysis and sulfuric acid hydrolysis, respectively. The RDACN shows high crystallinity of 82%, while SDACN presents low crystallinity due to the high degree of oxidation. Thus, SDACN has poorer thermal stability than RDACN and CN-M, but higher than CN-S. Compared to CN-M, SDACN with higher aldehyde contents as templates is beneficial to deposit more Ag nanoparticles with diameters of 30±4 nm and the resultant nanohybrids exhibit good antibacterial activities against both Gram-negative E. coli and Gram-positive S. aureus.

Amino-functionalized nanocrystalline cellulose as an adsorbent for anionic dyes

In this present work, amino-functionalized nanocrystalline cellulose (ANCC) was prepared by a process involving, (1) extraction of nanocrystalline cellulose (NCC) from fully bleached hardwood kraft pulp by sulfuric acid hydrolysis, (2) sodium periodate oxidation of NCC to yield the corresponding C-2/C-3 dialdehyde nanocellulose (DANC) and (3) grafting with ethylenediamine to obtain ANCC through a reductive amination treatment. Properties of DANC and ANCC were characterized by conductometric titration, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction and atomic force microscopy. It was found that the primary amine groups of ANCC (0.77–1.28 mmol g−1) increased with the increase of ethylenediamine dosage. The successful grafting was further evidenced by Kaiser test and FT-IR analysis. Zeta potential measurements showed that ANCCs were amphoteric, and their isoelectric points were between pH of 7–8. Chemical modifications of the cellulose nanowhiskers reduced the crystallinity but the initial cellulose I polymorph was retained. The cross-sectional dimension of nanowhiskers was slightly decreased from about 5–10 to 3–8 nm after the oxidation, and a better dispersibility was observed. ANCC sample was then applied as an adsorbent to remove anionic dyes in aqueous solutions. It demonstrated the maximum removal efficiency at acidic conditions. The acid red GR adsorption on ANCC fitted well with the Langmuir model, with a maximum theoretical adsorption capacity of 555.6 mg g−1. The adsorption of congo red 4BS, acid red GR and reactive light yellow K-4G followed pseudo second order kinetics, indicating a chemisorption nature.

Synthesis, identification of artificial antigen of catalpol and preliminary study of immunogenicity

The method of monoclonal antibody-based immunoassay has a great importance in the study of quality control of traditional Chinese medicine (TCM) and detection of trace components in vivo animals. Synthesis of small molecule artificial antigen is the prerequisite for the establishment of this method. In present study, catalpol-BSA was synthesized by sodium periodate oxidation method. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry ( MALDI-TOF-MS) and molecular exclusion chromatography showed that catalpol was successfully conjugated with BSA. The mice could specifically produce anti-catalpol antibodies with titer up to 1:8000. The artificial antigen of catalpol was successfully synthesized.

The Enzyme Linked Immunosorbent and Chemiluminescence Assay for the Detection of Human Chorionic Gonadotrophin Using Soybean Peroxidase as Label Enzyme

Soybean peroxidase (SBP) is characterized by relatively high heat resistance, wide substrate scope, good stability and broad pH applicability. These advantages led SBP to be used as labeledantibody for immunoassays. In this work, monoclonal antibody was linked with SBP to beta-HCG (Mab II-SBP) for enzyme-linked immunosorbent assay (ELISA) or chemiluminescence assay to explore its potential as an alternative to the widely used horseradish peroxidase (HRP) based ELISA. The Mab II-SBP was prepared by the sodium periodate oxidation method. The effects of enzyme coupling rate and molar ratio of Mab II to enzyme on assay performance were investigated. The optimum mass concentration ratio of Mab II and SBP was determined to be 1:3. The best coat concentration of the monoclonal antibody to alfa-HCG antibody (Mab I) was 4 μg/mL. Under optimum conditions, the HCG concentration was determined by the proposed ELISA assay with linear response range from 0.18 to 18 ng/mL and detection limit of 0.07 ng/mL at a signal-to-noise ratio of 3. Both enhancers, 3-(10’-phenothiazinyl) propane- 1-sulfonate (SPTZ) and 4-morpholinopyridine (MORPH), amplified chemiluminescence intensity nearly 200-fold in comparison to the SBP-luminol-H2O2 system. The present work demonstrates the feasibility and rationale of SBP-labeling antibodies for ELISA and chemiluminescence assays.

Sodium periodate oxidation of cellulose nanocrystal and its application as a paper wet strength additive

The oxidation of cellulose nanocrystal (CNC) by sodium periodate can generate aldehyde functions for crosslinking reactions or for further modification, which can extend the range of applications of CNC. In this paper, the effects of reaction conditions during the periodate oxidation of CNC, such as oxidant concentration, pH, temperature and oxidation time on the oxidized CNC yield and the aldehyde content, were investigated and an optimized reaction condition was identified. The generation of aldehyde groups on the CNC was confirmed by Fourier transform infrared spectroscopy analysis, and the decreased crystalline index was observed by X-ray diffraction. The transmission electron microscope observation showed the morphological changes of CNC after the oxidation. The oxidized CNC was used as a strength additive to paper, and the results showed that the dry tensile index was 32.6 % higher than the control sample, and the wet tensile index was reached to 3.08 N.m/g, at the oxidized CNC dosage of 1.2 %.

Porous cellulose facilitated by ionic liquid [BMIM]Cl: fabrication, characterization, and modification

Porous celluloses (PCs) were successfully prepared by a simple process of freezing the cellulose solution in ionic liquid, followed by solvent exchange and drying at normal temperature instead of the supercritical drying. PCs were composed of cellulose sheets of low crystallinity, as evidenced by SEM, XRD, TGA and FTIR, oriented into unidirectional structures when the cellulose concentration was low (1 %). When the cellulose concentration was high (4 %) the structure was twisted and randomly oriented. PCs had low apparent densities of 44–88 mg/cm3 and oil adsorption capacities ranging from 9.70 to 22.40 g/g (oil/PC) due to the ultralight porous structures. Oxidation of sodium periodate introduced dialdehyde groups into the porous structure. After the same reaction time, the aldehyde content of PC was much higher than the untreated cellulose counterpart. The resultant dialdehyde modified-PC had better urea adsorption than modified-viscose fiber. The high reactivity of PCs was related to the low crystallinity and porous structure.

Patterning and biofunctionalization of antifouling hyperbranched polyglycerol coatings.

We demonstrate the patterned biofunctionalization of antifouling hyperbranched polyglycerol (HPG) coatings on silicon and glass substrates. The ultralow fouling HPG coatings afforded straightforward chemical handles for rapid bioconjugation of amine containing biomolecular species. This was achieved by sodium periodate oxidation of terminal HPG diols to yield reactive aldehyde groups. Patterned microprinting of sodium periodate and cell adhesion mediating cyclic peptides containing the RGD sequence resulted in an array of covalently immobilized bioactive signals. When incubated with mouse fibroblasts, the HPG background resisted cell attachment whereas high density cell attachment was observed on the peptide spots, resulting in high-contrast cell microarrays. We also demonstrated single-step, in situ functionalization of the HPG coatings by printing periodate and peptide concurrently. Our results demonstrate the effectiveness of antifouling and functionalized HPG graft polymer coatings and establish their use in microarray applications for the first time.

Preparation and Characterization of Dialdehyde Nanocellulose

Dialdehyde nanocellulose (DANC) was prepared by periodate selective oxidation of secondary hydroxyl group of nanocrystalline cellulose (NCC). NCC and DANC samples were characterized by FT-IR, XRD and conductimetric titration. Aldehyde groups were introduced during the process of sodium periodate oxidation, which was confirmed by the FT-IR spectra. The aldehyde group content increased with the increase of sodium periodate. The crystallinity index (CrI) and crystallite size of the samples were continuously decreased with the increase of the oxidant.

Synthesis, characterization and properties of cellulose‐grafted glycine derivatives

ABSTRACTNovel Schiff base cellulose derivatives were successfully prepared by a bridge‐coupling reaction from dialdehyde cellulose (DAC), which was obtained by the selective oxidation of sodium periodate to cotton fibers, in which the glycine (Gly) was bonded onto the DAC chains by a Schiff base reaction with p‐nitrobenzaldehyde as a bridge. The structures of the graft copolymer (DAC‐g‐Gly) were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, solid‐state NMR, and scanning electronic microscopy. The thermodynamic properties were analyzed by thermogravimetric analysis and differential scanning calorimetry, and the biodegradability was also tested by the microbial degradation and the active sludge method. The results indicate that Gly was connected to DAC by chemical bonding, which changed the thermal stability, and that DAC‐g‐Gly could be biodegraded significantly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40929.

The Synthesis and Identification of a Ciprofloxacin Artificial Antigen

The artificial antigen ciprofloxacin-bovine serum albumin (CPFX-BSA) and ciprofloxacin-ovalbumin (CPFX-OVA) were synthesized by carbodiimide (EDC) method and sodium periodate oxidation method, respectively. These two kinds of antigens were identified by the UV absorption method and the animal immunization test, which showed that they were synthesized successfully. The successful synthesis of ciprofloxacin artificial antigen is important to establish immunoassay of ciprofloxacin.

Cross-Linking Soybean Protein into Periodate Oxidized Cotton Fabrics and their Physical Properties

The possibilities of obtaining active soybeancotton fabrics were examined. An effective two-stage method was developed. The first stage involves the formation of dialdehyde cellulose by the sodium periodate oxidation of cotton fabrics, which is able to form Schiff base with soybean protein. In the second stage, soybean grafted cotton fabrics were prepared by subsequent treatment of oxidized cotton fabrics with a solution of soybean protein in aqueous acetic acid. The technical conditions of oxidized cotton fabrics with soybean protein graft were studied, the internal structure and wearability of oxidized cotton fabric after soybean protein treatment were respectively measured and analyzed in this paper. The results of infrared spectra indicated that the C=N of chemical bond was formed between the aldehyde groups in oxidized cotton fabrics and the amino groups of soybean protein, and the soybean protein cross-linked on the surface of oxidized cotton fabrics by a series of reactions. Meanwhile, the calculating results on the separating peaks and imitating curves of X-ray diffractive curves illuminated that the crystallinity of the oxidized cotton fabric after soybean protein modification decreased from 67.83% to 62.35%. After soybean protein treatment, the breaking strength and elongation of the fabrics slightly decreased, whereas the wrinkle recovery angle and moisture absorption of cotton fabrics remarkably increased.

The identification of organic additives in traditional lime mortar

Abstract Organic-inorganic lime mortars were widely used in many ancient buildings due to their good performance in some fields (such as caking property, water repellency, weatherability, etc.). However, many ancient buildings and sites are suffering from various degrees of damage with the development of the economy and society and appropriate conservation and restoration are needed. The application of traditional construction materials, such as organic-inorganic lime mortars, attracts more and more attention in the conservation and restoration of ancient buildings in the recent years. So, the understanding of the components of original lime mortar which remained in ancient sites is of fundamental significance. In this work a set of analytical procedures to identify the organic additives in lime mortars by classical chemical analysis is proposed. The results show that using iodine-potassium iodide reagent, Benedict's reagent, reduction phenolphthalein reagent, Coomassie brilliant blue and sodium periodate oxidation glycerin acetyl acetone method could effectively detect a small amount of starch, reducing sugar, blood, protein and fatty acid ester that remained in ancient buildings’ lime mortars, respectively. These analytical methods are easy to operate with low detection limit, high accuracy and some other advantages.

Glycoproteome Quantification of Human Lung Cancer Cells Exposed to Amorphous Silica Nanoparticles

Engineered nanopartilces (NPs) are beginning to be used in many areas as their unique properties. Recent years, the safety concerns on engineered NPs have been increased as the absence of the systemic understanding of biological systems exposed to NPs. Although amorphous silica NPs are gradually used in cosmetics, foods and medicinal products, the potential biological effects of them exposed to biological systems are still not comprehensively elaborated. Herein, we studied the biological effects of silica NPs to human lung cancer cells by quantitative glycoproteomic strategy. A549 cells exposed to silica NPs were incubated with sodium periodate oxidation buffer to oxidize glycoproteins and then the cells were collected and cell lysis was carried out with the aid of ultrasonication in ice bath. The protein concentration was determined with Commasie brilliant blue stain. For control experiment, normal A549 cells were disposed as above mentioned method. Then the same amount of proteins extracted from A549 cells exposed to silica NPs or not were incubated with hydrazide beads to capture glycosylated proteins, respectively. The captured glycoproteins were digested with trypsin and PNGase F sequentially and both the non-glycopeptides and glycopeptides were collected, respectively. The obtained glycopeptides were used for the identification of the captured glycoproteins in both groups. And the collected non-glycopeptides were used for quantification of the captured glycoproteins through stable isotope dimethyl labeling. Therefore, the identification and quantification of glycoproteins was more reliable and sensitive for collecting both the information from non-glycopeptides and glycopeptides over only collecting the glycopeptides because of the quantification of glycoproteins with a large number of non-glycoproteins. The quantification results showed that the expression of several critical proteins relating to cellular carbohydrate metabolism, cell cycle, cell-cell signaling and interaction, cellular movement etc. have been changed significantly. Some of the differently expressed proteins are membrane proteins, which may relate with the cellular uptake of silica NPs. The proteomic platform is showing a promising power to quantitatively investigate the biological response of a biological system to NPs exposure.

Crosslinking Properties on Oxidized Cotton Cellulose and Chitosan with Low Molecular Weight

For exploiting green ecological cotton fiber products with the multifunction, a new cotton fiber crosslinked with chitosan of low molecular weight (CCCF) was prepared through the sodium periodate oxidation method. The reaction between amino groups of chitosan and aldehyde groups in the oxidized cotton cellulose occurred to obtain the CCCF in aqueous acetic acid solutions. The aldehyde group content in oxidized cotton cellulose increased markedly with the sodium periodate concentration, and the maximum weight gain of chitosan introduced on cotton fiber was 11.63% of the weight of cotton fibers. Furthermore, the crosslinking properties were respectively investigated by measurements of FT-IR and XPS spectra, the analysis indicated that the chitosan molecule was crosslinked on the surface of cotton fiber by the C=N covalent bond. This resulting CCCF is a novel ecological fiber and has more abilities of potential modification, which suggested useful information in planning applications for these modified cotton fibers.