In vitro and in vivo evaluation of DC-targeting PLGA nanoparticles encapsulating heparanase CD4+ and CD8+ T-cell epitopes for cancer immunotherapy.

Heparanase has been identified as a universal tumor-associated antigen, but heparanase epitope peptides are difficult to recognize. Therefore, it is necessary to explore novel strategies to ensure efficient delivery to antigen-presenting cells. Here, we established a novel immunotherapy model targeting antigens to dendritic cell (DC) receptors using a combination of heparanase CD4+ and CD8+ T-cell epitope peptides to achieve an efficient cytotoxic T-cell response, which was associated with strong activation of DCs. First, pegylated poly(lactic-coglycolic acid) (PLGA) nanoparticles (NPs) were used to encapsulate a combined heparanase CD4+ and CD8+ T-cell epitope alone or in combination with Toll-like receptor 3 and 7 ligands as a model antigen to enhance immunogenicity. The ligands were then targeted to DC cell-surface molecules using a DEC-205 antibody. The binding and internalization of these PLGA NPs and the activation of DCs, the T-cell response and the tumor-killing effect were assessed. The results showed that PLGA NPs encapsulating epitope peptides (mHpa399 + mHpa519) could be targeted to and internalized by DCs more efficiently, stimulating higher levels of IL-12 production, T-cell proliferation and IFN-γ production by T cells in vitro. Moreover, vaccination with DEC-205-targeted PLGA NPs encapsulating combined epitope peptides exhibited higher tumor-killing efficacy both in vitro and in vivo. In conclusion, delivery of PLGA NP vaccines targeting DEC-205 based on heparanase CD4+ and CD8+ T-cell epitopes are suitable immunogens for antitumor immunotherapy and have promising potential for clinical applications.

A Novel CreA-Mediated Regulation Mechanism of Cellulase Expression in the Thermophilic Fungus Humicola insolens.

The thermophilic fungus Humicola insolens produces cellulolytic enzymes that are of great scientific and commercial interest; however, few reports have focused on its cellulase expression regulation mechanism. In this study, we constructed a creA gene (carbon catabolite repressor gene) disruption mutant strain of H. insolens that exhibited a reduced radial growth rate and stouter hyphae compared to the wild-type (WT) strain. The creA disruption mutant also expressed elevated pNPCase (cellobiohydrolase activities), pNPGase (ß-glucosidase activities), and xylanase levels in non-inducing fermentation with glucose. Unlike other fungi, the H. insolens creA disruption mutant displayed lower FPase (filter paper activity), CMCase (carboxymethyl cellulose activity), pNPCase, and pNPGase activity than observed in the WT strain when fermentation was induced using Avicel, whereas its xylanase activity was higher than that of the parental strain. These results indicate that CreA acts as a crucial regulator of hyphal growth and is part of a unique cellulase expression regulation mechanism in H. insolens. These findings provide a new perspective to improve the understanding of carbon catabolite repression regulation mechanisms in cellulase expression, and enrich the knowledge of metabolism diversity and molecular regulation of carbon metabolism in thermophilic fungi.

Preparation of sequence-controlled triblock copolymer-grafted silica microparticles by sequential-ATRP for highly efficient glycopeptides enrichment.

As one of the most important subproteomes in eukaryote cells, N-glycoproteins play crucial roles in various of biological processes and have long been considered closely correlated with the occurrence, progression, and metastasis of cancer. Comprehensive characterization of protein N-glycosylation and association of their aberrant patterns to the corresponding cancer stage may provide a unique way to discover new diagnostic biomarkers and therapeutic drug targets. However, the extremely complex nature of biological samples and relatively low abundance of N-glycosylated proteins makes the enrichment of glycoprotein/glycopeptide a prerequisite for large scale N-glycosylation identification. In this work, we prepared sequence controlled triblock copolymer grafted silica-microparticles (TCP-SMs) by sequential atom transfer radical polymerization (sequential-ATRP) of monosaccharides and zwitterionic-ion monomers for highly efficient and selective glycopeptides enrichment. The triblock copolymer is composed of sequence defined poly zwitterionic-ion, poly-N-acetylglucosamine and poly mannose blocks. The glycopolymer blocks carrying densely packed pendent sugars are excellent mimics of the natural carbohydrate clusters and may induce multivalent carbohydrate-carbohydrate interaction (CCI) with the target glycopeptides. Therefore, increased retention of glycopeptides can be expected by the combination of CCI and zwitterionic-HILIC interaction. As a result, 1244 glycopeptides were identified after TCP-SMs enrichment from mouse liver, which are 65-120% higher than that obtained by homoglycopolymer or random-copolymer grafted silica microparticles prepared using the conventional free radical polymerization. These results demonstrate the critical role of sequence-defined block copolymer of TCP-SMs for obtaining enhanced affinity toward glycopeptides and the potential of this sequential-ATRP strategy to integrate different affinity moieties into one enrichment material to achieve deeper coverage in protein PTM mapping.

Effect of Membrane Pore Size on Membrane Fouling of Corundum Ceramic Membrane in MBR.

Ceramic membrane has emerged as a promising material to address the membrane fouling issue in membrane bioreactors (MBR). In order to optimize the structural property of ceramic membrane, four corundum ceramic membranes with the mean pore size of 0.50, 0.63, 0.80, and 1.02 µm were prepared, which were designated as C5, C7, C13, and C20, respectively. Long-term MBR experiments showed that the C7 membrane with medium pore size experienced the lowest trans-membrane pressure development rate. Both the decrease and increase of membrane pore size would lead to more severe membrane fouling in the MBR. It was also interesting that with the increase of membrane pore size, the relative proportion of cake layer resistance in total fouling resistance was gradually increased. The content of dissolved organic foulants (i.e., protein, polysaccharide and DOC) on the surface of C7 was quantified as the lowest among the different ceramic membranes. Microbial community analysis also revealed the C7 had a lower relative abundance of membrane fouling associated bacteria in its cake layer. The results clearly demonstrated that ceramic membrane fouling in MBR could be effectively alleviated through optimizing the membrane pore size, which was a key structural factor for preparation of ceramic membrane.

Biosynthesis of artificial starch and microbial protein from agricultural residue.

Growing populations and climate change pose great challenges to food security. Humankind is confronting a serious question: how will we feed the world in the near future? This study presents an out-of-the-box solution involving the highly efficient biosynthesis of artificial starch and microbial proteins from available and abundant agricultural residue as new feed and food sources. A one-pot biotransformation using an in vitro coenzyme-free synthetic enzymatic pathway and baker's yeast can simultaneously convert dilute sulfuric acid-pretreated corn stover to artificial starch and microbial protein under aerobic conditions. The ß-glucosidase-free commercial cellulase mixture plus an ex vivo two-enzyme complex containing cellobiose phosphorylase and potato α-glucan phosphorylase displayed on the surface of Saccharomyces cerevisiae, showed better cellulose hydrolysis rates than a commercial ß-glucosidase-rich cellulase mixture. This is because the channeling of the hydrolytic product from the solid cellulosic feedstock to the yeast mitigated the inhibition of the cellulase cocktail. Animal tests have shown that the digestion of artificial amylose results in slow and relatively small changes in blood sugar levels, suggesting that it could be a new health food component that prevents obesity and diabetes. A combination of the utilization of available agricultural residue and the biosynthesis of starch and microbial protein from non-food biomass could address the looming food crisis in the food-energy-water nexus.

Trypsin immobilization on hairy polymer chains hybrid magnetic nanoparticles for ultra fast, highly efficient proteome digestion, facile 18O labeling and absolute protein quantification.

In recent years, quantitative proteomic research attracts great attention because of the urgent needs in biological and clinical research, such as biomarker discovery and verification. Currently, mass spectrometry (MS) based bottom up strategy has become the method of choice for proteomic quantification. In this strategy, the amount of proteins is determined by quantifying the corresponding proteolytic peptides of the proteins, therefore highly efficient and complete protein digestion is crucial for achieving accurate quantification results. However, the digestion efficiency and completeness obtained using conventional free protease digestion is not satisfactory for highly complex proteomic samples. In this work, we developed a new type of immobilized trypsin using hairy noncross-linked polymer chains hybrid magnetic nanoparticle as the matrix aiming at ultra fast, highly efficient proteomic digestion and facile (18)O labeling for absolution protein quantification. The hybrid nanoparticle is synthesized by in situ growth of hairy polymer chains from the magnetic nanoparticle surface using surface initiated atom transfer radical polymerization technique. The flexible noncross-linked polymer chains not only provide large amount of binding sites but also work as scaffolds to support three-dimensional trypsin immobilization which leads to increased loading amount and improved accessibility of the immobilized trypsin. For complex proteomic samples, obviously increased digestion efficiency and completeness was demonstrated by 27.2% and 40.8% increase in the number of identified proteins and peptides as well as remarkably reduced undigested proteins residues compared with that obtained using conventional free trypsin digestion. The successful application in absolute protein quantification of enolase from Thermoanaerobacter tengcongensis protein extracts using (18)O labeling and MRM strategy further demonstrated the potential of this hybrid nanoparticle immobilized trypsin for high throughput proteome quantification.

Comparison of chromatographic performance of co-grafted silica using octadecene respectively with vinylpyrrolidone, vinylimidazole and vinylpyridine.

Three reversed-phase liquid chromatography (RPLC) stationary phases were obtained by using long-chain 1-octadecene (OD) co-grafted with three short-chain monomers, including N-vinylpyrrolidone (NVP), 1-vinylimidazole (VIm) and 4-vinylpyridine (VPy), respectively (noted as Sil@ODNVP, Sil@ODVIm and Sil@ODVPy). Peak broadening phenomenon in RPLC mode which resulted by short-chain was examined carefully. Compared with Sil@ODNVP, both of Sil@ODVIm and Sil@ODVPy had smaller peak width and higher column efficiency in the separation of 10 polycyclic aromatic hydrocarbons (PAHs), 7 alkyl benzenes, 7 aromatic acids, 7 aromatic esters and 9 phenols. In addition, VPy has the strongest ion exchange capacity than other two short-chains. In this case, we can see that VPy and VIm maybe more suitable to be used as functional monomeric modifiers of new chromatographic stationary phases.

[The study of the biodegradable biliary duct stent in vivo].

The present paper is aimed to evaluate safety and efficiency of a biodegradable biliary stent used in the Roux-en-Y cholangiojejunostomy of dogs in vivo. We separated 18 hybrid dogs into control group and experimental group randomly, with each group 9 dogs. The Roux-en-Y cholangiojejunostomy was carried out in the two groups. We placed the biodegradable stents into the anastomotic stoma of the dogs in the experimental group during the operation. After 3 months' close observation, we evaluated the degradable property and biocompatibility of the stents. We found that the morbidity rate of bile leakage in the dogs in the control group was much higher than that in the experimental group (P > 0.05). The X-ray photograph showed that the figures of the stents were complete and the stents were fixed at right place throughout the experimental period. The diameter of the dogs' common bile ducts of control group narrowed down obviously compared to those in the experimental group (P < 0.05). There were no impure materials adhered to the inside walls of the stents. The pathological test showed that there were no inflammation signs in mucous membrane and abnormal epithelium hyperplasia of the bile tract and jejunum. It can be concluded that the biliary duct stent, which was made with a mixture of poly-L-lactic acid (PLLA) and poly lactide-co-glycolide (PLGA), possesses qualities of relatively long degradable period (> 3 months) and good biocompatibility. Moreover, using the stent can effectively prevent bile leakage and anastomotic stom stenosis in the cholangio-intestinal anastomosis from happening.

Design and fabrication of a copolymer aspheric bi-convex lens utilizing thermal energy and electrostatic force in a dynamic fluidic.

The purpose of this paper is to use thermal energy and electrostatic force as an alternative to high-cost precision cutting or traditional injection molding in the fabrication of COC (cyclo-olefin copolymer) plastic aspheric bi-convex lenses with high Blu-Ray transmittance (92% at 405 nm). A glass substrate was used, and ultrasonic drilling defined the clear aperture of the aspheric bi-convex lens. The copolymer lens material was measured, filled and melted into the hole. A gradient electrical potential was applied between the top and bottom electrodes of the COC liquid droplet to control the profile of the lens. The thermal energy melted the COC into a dynamic fluid, and the electrostatic force controlled the aspheric morphology of the designed profile. The resulting lenses have a clear aperture of approximately 1.14 mm and a front focal length of 4.97 mm, and the spot size of the fabricated aspheric bi-convex lenses can be controlled to approximately 0.588 microm. This technology is capable of fabricating lenses for application in micro-optical systems.

Experimental investigation on liquefaction of plastic waste to oil in supercritical water.

In order to solve the problem of low thermal conductivity and high viscous molten liquid reaction product in the process of plastic liquefaction, the experiments of high impact polystyrene (HIPS) plastic liquefaction were carried out in supercritical water. In this paper, the effects of different operating conditions (temperature, time, feedstock concentration and pressure) on liquid products were studied. It is found that the novel phenomenon that the liquid products of HIPS plastic were mainly toluene and ethylbenzene rather than styrene, which was a product of polystyrene. The experimental results showed that plastic first depolymerized to form styrene and 1,3-diphenylpropane, which were then converted to toluene and ethylbenzene. The increase in temperature promoted this transformation process and some traces of polycyclic aromatic hydrocarbons also produced. At 490 °C, the maximum carbon liquefaction rate of 77.0 wt% was obtained, which was 6 times higher than the conventional pyrolysis, and the content of toluene and ethylbenzene were 14 wt% and 51.3 wt%, respectively. Increasing the reaction pressure and prolonging the reaction time all promoted the progress of the plastic liquefaction reaction, while increasing the feedstock concentration caused the carbon liquefaction rate to increase first and then slightly decrease.

Interferon-α-induced CD100 on naïve CD8+ T cells enhances antiviral responses to hepatitis C infection through CD72 signal transduction.

Objectives We investigated the effects of CD100 on naïve CD8+ T cells during hepatitis C virus (HCV) infection after interferon-α (IFN-α) therapy to clarify the mechanism underlying the effect of IFN-α in enhancing the antiviral response. Methods The CD100 molecules on subsets of CD8+ T cells were analysed with flow cytometry. The effects of CD100-overexpressing naïve CD8+ T cells were determined with ELISAs and an MTT cytotoxicity assay. The role of CD100-CD72 signal transduction was analysed with a neutralization and transwell assays. Results HCV infection reduced CD100 expression on CD8+ T cells, whereas IFN-α treatment significantly increased CD100 expression on naïve CD8+ T cells. The increased CD100 interacted with the CD72 receptor and enhanced PBMC cytokine secretion (IFN-γ and tumour necrosis factor-α) and cytotoxicity. Conclusions IFN-α-induced CD100 on naïve CD8+ T cells promotes PBMC cytokine secretion and cytotoxicity through CD100-CD72 signalling during HCV infection.

[Synthesis of core-shell hydrophilic polymer-silica hybrid material and its application in N-glycan enrichment].

Protein N-glycosylation is one of the most important post-translational modifications closely correlated with many important biological and pathological processes. The structural alterations of N-linked glycans in glycoproteins are always associated with many diseases, such as diabetes, heart failure and malignant tumors. Therefore, it is very important to establish sensitive methods for high-throughput N-glycan profiling. However, the low abundance of the N-glycoproteins and the heterogeneity of the N-glycans make it a challenge to analyse the protein glycosylation sensitively. In this work, we had synthesized core-shell hydrophilic polymer-silica hybrid materials (pGMAG-SiO2) for the efficient enrichment of protein N-glycans. Firstly, pGMAG-SiO2 was prepared by in situ growth of glucose polymer on the surface of silica microparticles using surface-initiated atom transfer radical polymerization (SI-ATRP) technique. The strong hydrophilicity of the material makes it suitable for the enrichment of N-glycans released from complex samples. Secondly, maltoheptaose and the N-glycans from chicken egg albumin were used as standard samples to optimize the enrichment conditions and evaluate the enrichment efficiency of pGMAG-SiO2. Finally, pGMAG-SiO2 was applied to the enrichment of N-linked glycans from human plasma proteins and 47 glycoforms were successfully identified after enrichment. These results demonstrated the high enrichment efficiency and significant application value of pGMAG-SiO2 in the analysis of N-glycans.

Synthesis and characterization of a novel nitric oxide fluorescent probe CdS-PMMA nanocomposite via in-situ bulk polymerization.

A novel nitric oxide (NO) fluorescent probe CdS-poly(methyl methacrylate) (PMMA) nanocomposites with different molar ratios of CdS quantum dots (QDs) to PMMA are developed successfully via in-situ bulk polymerization method. The optical properties of CdS/PMMA nanocomposites are studied by UV-Vis absorption spectra and fluorescence (FL) spectra in detail. It is demonstrated that the optical properties from such nanocomposite solution are tuned and stabilized by simply varying the concentration of CdS in the final product. X-ray diffraction (XRD) patterns of CdS-PMMA nanocomposite with higher loading of CdS show broad pattern for cubic CdS, which has narrow particle size distribution with less than 5 nm in PMMA observed by transmission electron microscopy (TEM). The surface morphological characterization of the CdS-PMMA nanocomposite has been done through atomic force microscopy (AFM). The thermo-gravimetric analyses (TGA) and differential scanning calorimetry (DSC) confirm the enhanced thermal stability of CdS-PMMA nanocomposites than PMMA. NO can coordinate with Cd(2+) as a ligand for transition metal complexes, which will cause a quenching effect on the fluorescence of CdS QDs. Therefore, a significant quenching effect on the fluorescence of the CdS-PMMA nanocomposite is observed in the presence of NO. The fluorescence responses are concentration-dependent and can be well described by the typical Stern-Volmer equation, and a linear calibration I0/I=1.0021+0.1944[NO] (R(2)=0.96052) is obtained in the range from 1.4×10(-5) to 9.3×10(-3) mol/L NO with a detection limit of 1.0×10(-6) mol/L (S/N=3).

[Alteration of CD100 expression on natural killer cells in chronic patients with hepatitis C virus before and after initiation of antiviral treatment].

OBJECTIVE: To investigate the changes of total natural killer (NK) cell number and its subset proportions and the expression levels of activation factor CD100 on NK cells in chronically hepatitis C virus (HCV) infected patients before and after initiation of antiviral treatment. METHODS: The frequencies of total NK cells and their subsets as well as CD100 expression on NK cells in HCV infected patients were detected by flow cytometry. The level of soluble CD100 (sCD100) in serum was measured by ELISA. The correlations of CD100 with alanine aminotransferase (ALT) and HCV-RNA were analyzed using Spearman correlation test. RESULTS: The proportion of CD56(dim) NK cell subset decreased, whereas CD56(neg) subset increased in chronic HCV infected patients as compared with healthy controls (P<0.05). The proportion of CD56(bright) NK cells was elevated and that of CD56(neg) NK subsets was reduced in HCV infected patients with early virological response (EVR) (P<0.05); however, total NK cells and their subsets returned to the normal in patients with sustained virological response (SVR) after the initiation of antiviral treatment. We also observed that sCD100 level declined significantly (P<0.05), whereas CD100 expression on NK cells slightly decreased as compared with healthy controls, but the difference was not statistically significant. The levels of sCD100 and CD100 expression on NK cells were markedly up-regulated in EVR patients (P<0.05) and dropped to the normal in SVR patients. Spearman correlation analysis showed that CD100 expression was positively related to ALT level and negatively associated with HCV-RNA titer in HCV infected patients (P<0.05). CONCLUSION: Decreased CD100 expression may be associated with viral persistence. As one of immune molecules regulated by IFN-α, CD100 seems to be involved in HCV clearance by NK cells.

[A novel immobilized trypsin on hydrophilic polymer modified Silica beads for proteome characterization].

A new type of immobilized trypsin was prepared using hydrophilic polymer modified silica microparticles (HPMSM) synthesized by atom transfer radical polymerization (ATRP) as the substrate material. ATRP modification led to densely packed hydrophilic polymer chains grafted on the microparticles surface which resulted in largely increased trypsin loading amount and minimized the nonspecific adsorption of proteins and peptides. Therefore, ultra-fast and highly efficient protein digestion was achieved with minimized sample loss. For standard protein bovine serum albumin (BSA), 1 min digestion led to the identification of 93 peptides, which covered 91% amino acid sequence of the protein. This immobilized trypsin was further successfully applied to the digestion of complex protein samples from yeast and 666 proteins were identified after 3 min digestion, which exceeded the number of identified proteins after 12 h solution digestion.

Interest of a new biodegradable stent coated with paclitaxel on anastomotic wound healing after biliary reconstruction.

OBJECTIVE: Benign biliary stricture of anastomotic stoma is frequent after biliary reconstruction. To prevent such a complication, a new paclitaxel-coated poly-L-lactide acid (PLLA) biodegradable biopolymer stent was designed. This original device was intended both to exert adequate mechanical support properties and to allow controlled drug delivery from the coating, with the goal of favoring wound healing after biliary reconstruction. METHODS: PLLA stents coated with three different paclitaxel concentrations were implanted in the biliary anastomosis of mongrel dogs (defining groups B, C, and D, respectively). Dogs without stent placement were included in control group A. Liver function tests and residual dosage of paclitaxel from each stent were measured. Histological data and α-smooth muscle actin immunohistochemical staining of biliary-enteric anastomosis were examined. RESULTS: There were no significant differences in liver function among the four groups and no bile leakage was observed. The paclitaxel-coated stents could slowly release paclitaxel for 9 weeks. In groups C and D, histological examinations showed less granulation tissue and glandular hyperplasia in biliary-enteric anastomosis than in control groups A and B. Submucosal collagen deposition was reduced and α-smooth muscle actin-positive cells decreased significantly, indicating the inhibition of myofibroblast proliferation in groups C and D. CONCLUSION: PLLA-paclitaxel-coated stents reduced the proliferation of granulation tissue and glandular hyperplasia, and inhibited the myofibroblast proliferation and extracellular matrix overdeposition during the healing process of biliary-enteric anastomotic stoma. This original device may offer a new way for the prevention of benign biliary structure.

Enhanced topical delivery of tetrandrine by ethosomes for treatment of arthritis.

The purpose of this work was to explore the feasibility of ethosomes for improving the antiarthritic efficacy of tetrandrine by topical application. It was found that tetrandrine was a weak base (pK(a) = 7.06) with pH-dependent partition coefficient. The spherical-shaped ethosomes were prepared by pH gradient loading method. Ex vivo permeation and deposition behavior demonstrated that the drug flux across rat skin and deposition of the drug in rat skin for ethosomes was 2.1- and 1.7-fold higher than that of liposomes, respectively. Confocal laser scanning microscopy confirmed that ethosomes could enhance the topical delivery of the drug in terms of depth and quantity compared with liposomes. The ethosomes were shown to generate substantial enhancement of therapeutic efficacy of tetrandrine on Freund's complete adjuvant-induced arthritis with regard to liposomes. These results indicated that ethosomes would be a promising carrier for topical delivery of tetrandrine into and across the skin.

Tacrolimus-loaded ethosomes: physicochemical characterization and in vivo evaluation.

The purpose of this work was to prepare and characterize a novel ethosomal carrier for tacrolimus, an immunosuppressant treating atopic dermatitis (AD), and to investigate inhibition action upon allergic reactions of mice aiming at improving pharmacological effect for tacrolimus in that commercial tacrolimus ointment (Protopic®) with poor penetration capability exhibited weak impact on AD compared with common glucocorticoid. Results indicated that the ethosomes showed lower vesicle size and higher encapsulation efficiency (EE) as compared with traditional liposomes with cholesterol. In addition, the quantity of tacrolimus remaining in the epidermis at the end of the 24-h experiment was statistically significantly greater from the ethosomal delivery system than from commercial ointment (Protopic®) (p<0.01), suggesting the greater penetration ability to the deep strata of the skin for ethosomes. Interestingly, tacrolimus-loaded ethosomes with ethanol, in contrast to that with propylene glycol, showed relatively higher penetration activity except insignificant differences in EE and polydispersity index. Topical application of ethosomal tacrolimus displayed the lowest ear swelling in BALB/c mice model induced by repeated topical application of 2,4-dinitrofluorobenzene compared to traditional liposomes and commercial ointment and effectively impeded accumulation of mast cells in the ear of the mice, suggesting efficient suppression for the allergic reactions. In conclusion, the ethosomal tacrolimus delivery systems may be a promising candidate for topical delivery of tacrolimus in treatment of AD.

Improved intestinal delivery of salmon calcitonin by water-in-oil microemulsions.

Therapeutic peptides are highly potent and specific in their functions, but difficulties in their oral administration require parallel development of viable delivery systems to improve their oral bioavailability. The objective of this study was to explore the feasibility of water-in-oil (w/o) microemulsions for improving the absorption of intraduodenally administered salmon calcitonin (sCT). The w/o microemulsions were prepared from medium chain triglyceride, Tween 80 and Span 80 or soybean phosphatidylcholine, propylene glycol and phosphate saline, and characterized by particle size and in vitro physical stability under dilution with different physiologically relevant diluents. The effects of addition of polymers such as hydroxypropylmethylcellulose and Carbomer into aqueous phase on the properties of microemulsions were assessed. sCT was efficiently encapsulated into microemulsions with nanoscaled diameter ranged from about 6 to 134nm. As expected from the non-ionic nature of the investigated microemulsions, the physical stability, evaluated by visual inspection, the particle size and leakage percent under dilution, was found to be unaffected by pH and/or ionic strength of diluents and it was opposite for the microemulsions with ionic components. In addition, the dilution extent had a pronounced effect on the physical stability of the diluted microemulsions. The effect of polymers added into aqueous phase of the microemulsions on the absorption of the drug entrapped in microemulsions with different components was investigated. The optimized microemulsions were shown to generate substantial enhancement (up to 4-fold) of relative pharmacological activity of sCT with regard to the control solution of the drug. This indicated that the w/o microemulsions could offer the potential to significantly improve intestinal absorption of sCT.

Protein pattern assembly by active control of a triblock copolymer monolayer.

We present an electrically programmable technique that can rapidly assemble proteins into high-resolution, arbitrarily shaped patterns. Controlled protein adsorption is achieved by switching the nanoscale surface arrangement of a triblock copolymer monolayer on microelectrodes in an engineered microfluidic device via an electric potential. Our technique is the first capable of configuring differential protein densities into patterns by varying the applied control voltage, providing the possibility to tune signals for complex analytes, test conditions, or quantification.