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Chinese forest frog ovum oil is a medicinal food high in cholesterol. In the current study, we evaluated the relative efficiency of β-cyclodextrin, crosslinked β-cyclodextrin, and silica gel adsorption on cholesterol removal from Rana chensinensis ovum oil. Beta-cyclodextrin had the highest cholesterol reduction rate (60.84 ± 4.45%) among the three methods. We further evaluated the efficiency of cholesterol removal by beta-cyclodextrin in the presence of ethanol and higher (55°C) temperature. This resulted into cholesterol removal rate of as high as 76%. Interestingly, monounsaturated fatty acids increased from 4.96% to 29.12% after cholesterol removal. We conclude that beta-cyclodextrin is an excellent adsorbent for removing cholesterol from ovum oil. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles were electrodeposited on graphene modified glassy carbon electrode to form a modified electrode, and the electrode was characterized with scanning electron microscopy (SEM). At the modified electrode, rutin, a natural flavonoid, shows a couple of well-defined redox peaks, which is corresponded to the reduction and reoxidation of rutin. The electrochemical behaviors of rutin at the electrode were investigated, and the results indicated that the electrode reaction is controlled by adsorption process. Under the optimal conditions, the peak currents of differential pulse voltammetry (DPV) increased linearly with the rutin concentration in the range from 2.0 × 10-8 to 8.0 × 10-5M with a limit of detection of 6.7 × 10-9 M. The as-prepared electrode was successfully used for the selective determination of rutin in tablet, displaying a potential application of graphene composite modified electrode. [ABSTRACT FROM AUTHOR]

The development of nonfouling biomaterials to prevent nonspecific protein adsorption and cell/bacterial adhesion is critical for many biomedical applications, such as antithrombogenic implants and biosensors. In this work, we polymerize two types of hydroxy-functional methacrylates monomers of 2-hydroxyethyl methacrylate (HEMA) and hydroxypropyl methacrylate (HPMA) into polymer brushes on the gold substrate via surface-initiated atom transfer radical polymerization (SI-ATRP). We systematically examine the effect of the film thickness of polyHEMA and polyHPMA brushes on their antifouling performance in a wide range of biological media including single-protein solution, both diluted and undiluted human blood serum and plasma, and bacteria culture. Surface plasmon resonance (SPR) results show a strong correlation between antifouling property and film thickness. Too thin or too thick polymer brushes lead to large protein adsorption. Surfaces with the appropriate film thickness of ∼25−45 nm for polyHPMA and ∼20−45 nm for polyHEMA can achieve almost zero protein adsorption (<0.3 ng/cm2) from single-protein solution and diluted human blood plasma and serum. For undiluted human blood serum and plasma, polyHEMA brushes at a film thickness of ∼20−30 nm adsorb only ∼3.0 and ∼3.5 ng/cm2proteins, respectively, while polyHPMA brushes at a film thickness of ∼30 nm adsorb more proteins of ∼13.5 and ∼50.0 ng/cm2, respectively. Moreover, both polyHEMA and polyHPMA brushes with optimal film thickness exhibit very low bacteria adhesion. The excellent antifouling ability and long-term stability of polyHEMA and polyHPMA brushes make them, especially for polyHEMA, effective and stable antifouling materials for usage in blood-contacting devices. [ABSTRACT FROM AUTHOR]

Human blood plasma and serum pose significant challenges to implanted devices because of highly unfavorable nonspecific protein adsorption on the surface. In this work, we introduce an improved two-step method to immobilize initiator thiols on a gold substrate for the surface-initiated atom-transfer radical polymerization (SI-ATRP) of hydroxypropyl methacrylate (HPMA). We investigate protein adsorption from a single-protein solution, diluted (10%) and undiluted (100%) human blood plasma, and serum on the poly(HPMA) brushes with different film thicknesses using surface plasmon resonance (SPR) sensors. SPR results show a correlation between antifouling properties and film thickness; that is, the poly(HPMA) brushes exhibit high protein resistance at medium film thicknesses of ∼25−40 nm (e.g. <0.3 ng/cm2for single-protein adsorption and 10% human blood plasma and serum, ∼24.5 ng/cm2for 100% human serum, and ∼52.8 ng/cm2for 100% human plasma at a thickness of ∼29 nm). With an optimal film thickness and surface roughness, the poly(HPMA) brush also demonstrates its high resistance to fibroblast adhesion. This work provides an alternative surface polymerization approach to preparing effective antifouling poly(HPMA) materials for potential applications in blood-contacting medical devices. [ABSTRACT FROM AUTHOR]

Rationaldesign of effective antifouling polymers is challenging but importantfor many fundamental and applied applications. Herein we synthesizeand characterize an N-acryloylaminoethoxyethanol(AAEE) monomer, which integrates three hydrophilic groups of hydroxyl,amide, and ethylene glycol in the same material. AAEE monomers werefurther grafted and polymerized on gold substrates to form polyAAEEbrushes with well-controlled thickness via surface-initiated atomictransfer radical polymerization (SI-ATRP), with particular attentionto a better understanding of the molecular structure–antifoulingproperty relationship of hydroxyl-acrylic-based polymers. The surfacehydrophilicity and antifouling properties of polyAAEE brushes as afunction of film thickness are studied by combined experimental andcomputational methods including surface plasmon resonance (SPR) sensors,atomic force microscopy (AFM), cell adhesion assay, and moleculardynamics (MD) simulations. With the optimal polymer film thicknesses(∼10–40 nm), polyAAEE-grafted surfaces can effectivelyresist protein adsorption from single-protein solutions and undilutedhuman blood plasma and serum to a nonfouling level (i.e., <0.3ng/cm2). The polyAAEE brushes also highly resist mammaliancell attachment up to 3 days. MD simulations confirm that the integrationof three hydrophilic groups induce a stronger and closer hydrationlayer around polyAAEE, revealing a positive relationship between surfacehydration and antifouling properties. The molecular structure–antifoulingproperties relationship of a series of hydroxyl-acrylic-based polymersis also discussed. This work hopefully provides a promising structuralmotif for the design of new effective antifouling materials beyondtraditional ethylene glycol-based antifouling materials. [ABSTRACT FROM AUTHOR]