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Hemoperfusion using metal ion affinity adsorbent is a promising method to remove human testosterone in plasma. Due to the leakage of metal ion from the adsorbents, there is no metal ion affinity adsorbent for hemoperfusion. In this study, chitosan was used to coat the adsorbent for preventing the leakage of Zn2+ loaded. Meanwhile, freeze-drying method was used to enhance adsorption capacity of Zn2+-loaded cellulose beads for testosterone. The results indicate that after the adsorbent was coated by 0.02% chitosan solution, the highest adsorption percentage reached 48%, during adsorption, the Zn2+ concentration in plasma did not increase; the adsorption capacity of the adsorbent can be significantly enhanced by freeze-drying. The results may be caused by porosity of the adsorbent enlarged via freeze-drying and improved stability by coating with chitosan. In addition, the adsorbent shows better selectivity and storage stability and could be a potential adsorbent to treat prostate cancer.

Hemoperfusion using metal ion affinity adsorbent is a promising method to remove human testosterone in plasma. Due to the leakage of metal ion from the adsorbents, there is no metal ion affinity adsorbent for hemoperfusion. In this study, chitosan was used to coat the adsorbent for preventing the leakage of Zn

Spacer can effectively reduce the steric hindrance and synergistic effect of the hydrophilic and hydrophobic ligands immobilized in adsorbents can improve the specific adsorption for low-density lipoprotein (LDL). In this paper, in order to improve the adsorption capacity for the Low-density lipoprotein-cholesterol (LDL-C), specifically, amphiphilic adsorbent based on polyvinyl alcohol (PVA) containing cholesterol ligand and sulfonic dextran ligands was synthesized. All kinds of factors affecting the synthesis yield and adsorption properties were studied in detail. Results showed that the amphiphilic PVA adsorbent has higher adsorption capacity for total cholesterol (TC), (LDL-C), triglyceride (TG), and lower adsorption capacity, and percentage for high-density lipoprotein-cholesterol (HDL-C), while the ligand ratio of cholesterol to sulfonic ligands is 1.57:1, the adsorption percentage and adsorption capacity for TC, LDL-C, TG, and HDL-C were 54.4%, 67.6%, 42.5%, 10.4% and 4.02, 3.612, 2.154, 0.168 mg/g, respectively.

Rice dreg protein hydrolysates (RDPH) can potentially be used as natural antioxidants for a variety of emulsion-type food systems. They contained 89.9% protein, 934.2 mg/g total amino acids with 517.7 mg/g total hydrophilic amino acids, and 78% peptides smaller than 5 kDa. Here, the physical and oxidative stabilities of corn oil-in-water emulsions (10 wt.% lipid) containing RDPH (0–20 mg/mL) and stabilized by Tween-20 were investigated as a function of RDPH concentration and pH. The results showed that emulsions with RDPH and Tween-20 emulsions did not experience coalescence (when RDPH concentration

A novel colorimetric sensor for the rapid and label-free detection of vanillin, based on the combination of photonic crystal and molecular imprinting technique, was developed. The sensing platform of molecularly imprinted photonic hydrogel (MIPH) was prepared by a noncovalent and self-assembly approach using vanillin as a template molecule. Morphology characterization by scanning electron microscope (SEM) showed that the MIPH possessed a highly ordered three-dimensional (3D) macroporous structure with nanocavities. The vanillin recognition events of the created nonocavities could be directly transferred into readable optical signals through a change in Bragg diffraction of the ordered macropores array of MIPH. The Bragg diffraction peak shifted from 451 to 486 nm when the concentration of the vanillin was increased from 10(-12) to 10(-3) mol L-1 within 60 s, whereas there were no obvious peak shifts for methyl and ethyl vanillin, indicating that the MIPH had high selectivity and rapid response for vanillin. The adsorption results showed that the hierarchical porous structure and homogeneous layers were formed in the MIPH with higher adsorption capacity. The application of such a label-free sensor with high selectivity, high sensitivity, high stability, and easy operation might offer a potential method for rapid real-time detection of trace vanillin.

The whole blood immuno-adsorption (WBIA) system, using an adsorbent to remove pathogenic antibodies of Myasthenia Gravis (MG), was studied. Cellulose-tryptophan adsorbent was synthesized and purified in our lab. Experimental autoimmune myasthenia gravis (EAMG) rabbits were passively transferred with immunoglobulin from patients with myasthenia gravis. The rabbits underwent extracorporeal whole blood adsorption for 2 hours. Results showed no significant damage to blood cells and no changes in the concentrations of electrolytes. Total protein decreased by 12.6% (P

The mechanism of recognition and interactions of LDL (low density lipoprotein) with different charged ligands on adsorbents was studied. Tryptophan, lysine residues and carboxyl terminus on LDL were chemically modified by pyridoxal 5-phosphate (PP), N-Ethyl-N′-[3-(dimethylamino)propyl]carbodiimide (EDC) and N-bromosuccinimide (NBS), respectively. Due to the effectiveness of l -lysine in the removal of LDL-C (LDL-cholesterol), it was selected to study the interaction of ligand with the modified LDL. Experimental results show that positive charge on the surface of LDL interacts with the negative charged carboxyl groups of l -lysine by electrostatic force, thus resulting in the adsorption of LDL by the absorbent. We also found that increasing the positive charge on the surface of LDL could enhance the adsorption capacity of the adsorbent. On the contrary, increasing the negative charge could decrease the adsorption ability. Thus, different adsorbents containing sulfonic groups, phosphoric groups, l -lysine and carboxyl groups as the ligand were synthesized for investigating the effect of electric charge on their adsorption capacity. Results show that the adsorption capacity increases with the increase of the electronegativity of the ligand on the adsorbent.

The use of quartz crystal microbalance (QCM) for on-line monitoring of the adsorption of low-density lipoprotein (LDL) onto cholesterol-modified dextran (CMD) was described. Kinetics studies were made and molecule interaction mechanism was discussed. Experimental results showed that kinetic curves fitted Langmuir adsorption equation quite well. When LDL concentrations (ng/μl) were 9.9, 12.38 and 14.14, respectively, the apparent rate constants (s− 1) and adsorption capacities (ng/cm2) were estimated to be 0.0477, 0.0536, 0.0628 and 124.5, 161.6, 194.3, respectively. The maximal LDL adsorption capacity attained 329.6 ng/cm2 and the adsorptive efficiency was calculated to be 72.91%. Moreover, a new method to evaluate the adsorption behavior was provided.

Dextran adsorbent with amphiphilic ligands for adsorption of low-density lipoprotein (LDL) was prepared by the following procedures. Cholesterol group was linked to Dextran G 75 by reacting with cholesterol N-(6-isocyanatohexyl) carbamate in the presence of pyridine in DMSO at 80. In order to introduce the hydrophilic moiety, it was then reacted with chlorosulfonic acid in formamide which introduced the sulfonic group. Adsorption capacity of the adsorbent was studied which showed the removal of LDL-cholesterol (LDL-C), total cholesterol (TC) and TG to be 1.916, 2.132 and 1.349 mg/ml, respectively without significantly affecting total protein levels in the plasma. Moreover, the adsorbent has a better selectivity in removing LDL-C, TC, TG compared to dextran which has only hydrophobic or hydrophilic ligand.

Cellulose, a natural polymer, has been widely used in blood purification due to its good biocompatibility, and excellent processing which can be easily formulated into beads, membranes and hollow fibers. Sorbent-perfusion is a novel approach of blood purification which can specifically remove endogenous and exogenous pathogenic toxins from the blood of patients [1]. The technique involves passing whole blood or plasma of the patient through a cartridge filled with an adsorbent which can easily adsorb the toxin molecules, see Figure 1 a,b. According to selectivity, generally adsorbents can be classified as broad spectrum, affinity adsorbents and immuno-adsorbents, of which the latter has the highest selectivity [2-5]. Materials, most commonly used are activated charcoal [6], porous resins and fibers. The pathogenic substances in the blood of patients are adsorbed by the adsorbent via hydrophilic (electro-static forces) or hydrophobic interactions. Macroporous resins usually show high adsorption capacities especially for the removal of high molecular weight or “middle molecules” toxins [7-9].

Agar-gel resin with tryptophan as ligand was synthesized as an adsorbent for the removal of Immunoglobulin E (IgE) in bronchial asthma. Factors affecting the adsorption properties of the adsorbent, such as the different kind of amino acid linked to the carrier, NaOH concentration and amount of epichlorohydrin used in activation, were studied in detail. The effect of spacer on the adsorption capacity was also investigated. Results showed that the agar-tryptophan adsorbent with a spacer could enhance the adsorption capacity to 70.73% (1309.403IU/g agar-gel), which was higher than that without spacers (53%). The selectivity and hemocompatibility of the adsorbent were also examined, which showed good selectivity for IgE and satisfactory blood compatibility.

A new amphiphilic adsorbent for the removal of low-density lipoprotein (LDL) was prepared according to the literature (Artif. Cells Blood Subs., Immob. Biotechnol. 30 (4) (2002) 285). The effects of sulfonation and grafting time of cholesterol on the swelling property of adsorbent were studied. When sulfonation and grafting time of cholesterol was 3 and 5 h, respectively, the amphiphilic adsorbent had a high adsorption capacity for LDL without significantly adsorbing high-density lipoprotein. The adsorption capacity of the adsorbent for the removal of LDL, total cholesterol (TC) and TG was 1.916, 2.132, 1.349 mg/ml, respectively. Hyperlipidemia rabbits were developed by feeding with fodder containing high content of cholesterol or yolk, which was then perfused with an optimal amount of amphiphilic adsorbent. After 2 h hemoperfusion, the LDL levels decreased from 3.619+/-0.354 to 0.724+/-0.07 mmol/l, which showed that the adsorbent could effectively remove LDL without side effect.