Dextran T10 Research Articles

Quantitative characterization of non-specific interaction of two globular proteins with Dextran T70 in a binary mixture.

In a bid to quantify the contribution of molecular structure to non-specific interactions leading to functionally important structural changes in cellular processes, the self-interaction of dextran-T70 (DT70) and its interaction with each of bovine serum albumin (BSA) and ovomucoid trypsin inhibitor (OVO) were studied at pH 7.4 between 5 and 37°C. The dependences of the apparent molecular weight of each of BSA, OVO and DT70 on the concentration of DT70 were independent of temperature. The activity coefficient of the interaction of each species on DT70 concentration was also independent of temperature. The change in activity coefficient was however dependent on the molecular structure and size of the interacting species. The energy of insertion of each macromolecule in DT70 increased in the order DT70 > BSA > OVO. These findings show that although the enthalpic contribution is negligible, the extent of the entropic contribution to the macromolecular activity coefficient of interaction is chiefly the consequence of the exclusion volume of the interacting macromolecules.

Modification of the Loop Region Near the Substrate Tunnel to Alter the Hydrolytic Process of Dextranase

Dextranases are hydrolases that exclusively catalyze the disruption of α−1,6 glycosidic bonds. A series of variant enzymes were obtained by comparing the sequences of dextranases from different sources and introducing sequence substitutions. A correlation was found between the number of amino acids in the 397–401 region and the hydrolytic process. When there were no more than 5 amino acids in the 397–401 region, the enzyme first hydrolyzed the dextran T70 to a low molecular weight dextran with a molecular weight of about 5000, then IMOs11IMOs: isomaltooligosaccharides. G: glucose, G2: maltose, G3: maltotriose, G4: maltotetraose, G5: maltopentaose, G6: maltohexaose, G7: maltoheptaose, IG2: isomaltose, IG3: isomaltotriose, IG4: isomaltotetraose, IG5: isomaltopentaose appeared in the system if the degradation continued, showing a clear sequential relationship. And when there are more than 5 amino acids in the 397–401 region, IMOs were produced at the beginning of hydrolysis and continue to increase throughout the hydrolytic process. At the same time, we investigated the enzymatic properties of the variants and found that the hydrolytic rate of A-Ca was 11 times higher than that of the original enzyme. The proportion of IMOs produced by A-Ca was 80.68%, which was nearly10% higher than the original enzyme, providing a new enzyme for the industrial preparation of IMOs.

Cloning of Cold-Adapted Dextranase and Preparation of High Degree Polymerization Isomaltooligosaccharide

Intestinal diseases are mainly caused by a decrease in the relative abundance of probiotics and an increase in the number of pathogenic bacteria due to dysbiosis of the intestinal flora. High degree polymerization isomaltooligosaccharide (IMO) can promote probiotic metabolism and proliferation. In this study, the dextranase (PsDex1711) gene of marine bacterial Pseudarthrobacter sp. RN22 was cloned and expressed in Escherichia coli BL21 (DE3). The optimal pH and temperature of the dextranase were 6.0 and 30 °C, respectively, showing the highest stability at 20 °C. The dextran T70 could be hydrolyzed to produce IMO3, IMO4, IMO5, and IMO6 with a high degree of polymerization. The hydrolysate of 1 mg/mL could significantly promote the growth of Lactobacillus and Bifidobacterium after 12 h culture and the formation of biofilms by 58.2%. The hydrolysates could promote the proliferation of probiotics. Furthermore, the IC50 of scavenging rate of DPPH, hydroxyl radical, and superoxide anion was less than 20 mg/mL. This study provides a crucial theoretical basis for the application of dextranase such as pharmaceutical and food industries.

Increasing immunoglobulin G adsorption in dextran-grafted protein A gels.

The formation of a stable spatial arrangement of protein A ligands is a great challenge for the development of high‐capacity polymer‐grafted protein A adsorbents due to the complexity in interplay between coupled ligands and polymer chain. In this work, carboxymethyl dextrans (CMDs) with different molecular weight were introduced to provide stable spatial ligand arrangement in CMD‐grafted protein A gels to improve IgG adsorption. The result showed that coupling of protein A ligand in CMD‐grafted layer had no marked influence on pore size and dextran layers coupled with the ligands were stable in experimental range of salt concentrations. The result of IgG adsorption revealed that carboxymethyl dextran T10, a short CMD, was more suitable as a scaffold for the synthesis of high‐capacity protein A gels. Moreover, the maximal adsorption capacity for IgG was obtained to be 96.4 mg/g gel at ionic capacities of 300–350 mmol/L and a ligand density of 15.2 mg/g gel. Dynamic binding capacity for IgG exhibited a higher capacity utilization in CMD‐grafted protein A gels than non‐grafted protein A gel. The research presented a tactics to establish a stable dextran layer coupled with protein A ligands and demonstrated its importance to improve binding capacity for IgG.

Effects of saccharides on the rheological and gelling properties and water mobility of egg white protein

Egg white protein (EWP) has excellent gelling and rheological properties but is susceptible to various external conditions, such as the addition of saccharides. In this study, the effects of glucose, maltodextrin, dextran T20, and dextran T40 on the rheological and gelling properties and water mobility of EWP were elucidated. Results showed that the native EWP solution formed a more elastic gel, whereas the EWP–saccharide mixtures formed a more viscous gel. Moreover, the addition of saccharides would reduce the hardness of EWP gel because adding saccharides to the EWP solution might inhibit the denaturation and unfolding of the EWP molecules. The results of texture profile analysis showed that the gel hardness of the EWP–saccharide gels was weak when the molecular weight of the saccharides introduced into the EWP solution was large. Moreover, the saccharide loosened the secondary structure of EWP in EWP–saccharides gel and this condition decreased the gel hardness. Furthermore, low-field nuclear magnetic resonance revealed that the addition of saccharides lowered the formation rate of EWP gels by delaying the migration of immobile water. The work provides an important theoretical basis for the application of EWP in saccharide systems.

Expression, purification and characterization of a cold-adapted dextranase from marine bacteria and its ability to remove dental plaque

Dental plaque is a high-incidence health concern, and it is caused by Streptococcus mutans. Dextranase can specifically hydrolyze ɑ-1,6-glycosidic linkages in dextran. It is commonly used in the sugar industry, in the production of plasma substitutes, and the treatment and prevention of dental plaque. In this research work, we successfully cloned and expressed a cold-adapted dextranase from marine bacteria Catenovulum sp. DP03 in Escherichia coli. The recombinant dextranase named Cadex2870 contained a 2511 bp intact open reading frame and encoded 836 amino acids. The expression condition of recombinant strain was 0.1 mM isopropylthio—galactoside (IPTG), and the reduced temperature was 16 °C. The purified enzyme activity was 16.2 U/mg. The optimal temperature and pH of Cadex2870 were 45 °C and pH 8, and it also had catalytic activity at 0 °C. The hydrolysates of Cadex2870 hydrolysis Dextran T70 are maltose, maltotetraose, maltopentose, maltoheptaose and higher molecular weight maltooligosaccharides. Interestingly, 0.5% sodium benzoate, 2% xylitol, 0.5% sodium fluoride, 5% propanediol, 5% glycerin and 2% sorbitol can enhance stability Cadex2870, which are additives in mouthwashes. Additionally, Cadex2870 reduced the formation of dental plaque and effectively degraded formed plaque. Therefore, Cadex2870 shows great promise in commercial applications.

Characterization of an Alkaline GH49 Dextranase from Marine Bacterium Arthrobacter oxydans KQ11 and Its Application in the Preparation of Isomalto-Oligosaccharide

A GH49 dextranase gene DexKQ was cloned from marine bacteria Arthrobacter oxydans KQ11. It was recombinantly expressed using an Escherichia coli system. Recombinant DexKQ dextranase of 66 kDa exhibited the highest catalytic activity at pH 9.0 and 55 °C. kcat/Km of recombinant DexKQ at the optimum condition reached 3.03 s−1 μM−1, which was six times that of commercial dextranase (0.5 s−1 μM−1). DexKQ possessed a Km value of 67.99 µM against dextran T70 substrate with 70 kDa molecular weight. Thin-layer chromatography (TLC) analysis showed that main hydrolysis end products were isomalto-oligosaccharide (IMO) including isomaltotetraose, isomaltopantose, and isomaltohexaose. When compared with glucose, IMO could significantly improve growth of Bifidobacterium longum and Lactobacillus rhamnosus and inhibit growth of Escherichia coli and Staphylococcus aureus. This is the first report of dextranase from marine bacteria concerning recombinant expression and application in isomalto-oligosaccharide preparation.

Dextran-induced modifications of calcium carbonate particles precipitated during carbonatation

The effects of high and low molecular mass dextran (T2000 and T40) on the size and shape of particles precipitated during carbonatation and their correlation with filtration performances were key to this study. Varying contents of T2000 and T40 dextran in sugar solutions corresponding to DS contents of thin juice were investigated. For particle size and shape analysis, static image analysis and laser particle size analysis were used. Both methods, static image analysis and laser diffraction, revealed that the presence of T2000 and T40 dextran leads to a higher amount of large-sized particles at the expense of small-sized particles, indicating pronounced agglomeration. The additional evaluation of shape parameters (circularity, roundness, solidity) obtained from static image analysis indicates that the agglomeration is oriented in the absence and in the presence of lower T40 dextran levels. Besides, non-oriented agglomeration, resulting in more round agglomerates with smoother surfaces, was found for samples loaded with T2000 dextran and high T40 dextran levels. Only the latter samples have shown to negatively affect the filtration performance. Thus, in the presence of T2000 dextran and high T40 dextran levels, the filtration was hampered. This appears to be mainly caused by a tighter packing of more round calcium carbonate agglomerates in the porous structure of the filter cake.

Quantitative characterization of temperature-independent polymer-polymer interaction and temperature-dependent protein-protein and protein-polymer interactions in concentrated polymer solutions.

To study the effect of non-specific interactions arising from proteins being in a crowded environment on physiological processes, the self-interaction of concentrated Dextran T70 and Ficoll 70 and the interactions between a dilute protein and these polymeric macromolecules were quantified using non-ideal tracer sedimentation equilibrium. Sedimentation equilibria of each polymer were measured between 5 and 37°C, and sedimentation equilibria of 2mgcm-3 superoxide dismutase (SOD) in 0-0.1gcm-3 of each polymer was also measured. Results were analyzed using a model-free thermodynamic virial expression of activity coefficients in terms of the concentration of polymer and a structural model using a statistical thermodynamics approximation. The equilibrium gradients of each of the polymers suggest repulsive interaction, which is independent of temperature. However, the net repulsive interaction between superoxide dismutase (SOD) species and the polymers is dependent on temperature. The ratio of the solvation energy of SOD in Dextran T70 to that in Ficoll 70, lnγSOD(Dex)/lnγSOD(Fic) at the same w/v concentration was about 1.8 at 37°C, 1.6 at the intermediate temperature, and ranges from 1.2 to 1.6 at 5°C over the entire concentration range. The enthalpy and entropy of interaction of SOD with dilute Dextran T70 are - 14kJmol-1 and - 5.6JK-1 mol-1, respectively. For SOD in dilute Ficoll 70, the enthalpy and entropy are - 8.1kJmol-1 and 12.9JK-1mol-1, respectively. Thus, Dextran T70 contributes more to the attractive protein-polymer interaction and to self-association of protein than Ficoll 70 and reasons for this are discussed.

Theoretical and experimental investigation of mass transfer in aqueous two-phase systems based on linear and branched polymers

In this work the mass transfer of the amino acid, l-serine, in two different aqueous two phase systems (ATPS) was analysed. One ATPS is based on a hyperbranched polyesteramide and dextran T40 and the second one is formed by polyethylene glycol and dextran T40. The mass transfer was analysed experimentally and theoretically as well. The experimental analysis of the mass transfer was carried out in a Nitsch cell; whereas the mass transfer across the interface was modelled by the density gradient theory providing an expression for the chemical potential in the inhomogeneous region. As thermodynamic model the Lattice Cluster theory was used to account for the structure of the polymers. To consider the association, it was combined with a Wertheim approach. The mass transfer approach based on the density gradient theory was extended to a quaternary system for the first time and applied to model the mass transfer of l-serine in both ATPS. It was found that l-serine enriches at the interface during the mass transfer. The developed mass transfer approach was successfully applied to model the interfacial mass transfer of l-serine in both ATPS.

Uniform polysaccharide composite microspheres with controllable network by microporous membrane emulsification technique.

High resolution has been constantly pursued in both preparative and analytical chromatography. Chromatographic media are a key factor during the entire separation process. Tailor-made chromatographic media have gained more attention because of their adjustable structure appropriate for application. Uniform polysaccharide composite microspheres were prepared with a mixture of agarose and dextran solution by membrane emulsification technique for the first time. Their pore structure was deliberately regulated by adjusting boththe polysaccharide composition and the molecular weight of dextran. Compared with pure agarose microspheres, polysaccharide composite microspheres had a higher separation resolution and their separation range was controllable. By increasing agarose concentration and decreasing dextran concentration at the same time during the preparation of composite microspheres, the mean pore size increased first and then decreased later, and also the pore size distribution became narrower. By increasing the molecular weight of dextran, the pores became smaller with a narrower pore size distribution. Microspheres with a composition of 10% agarose/2% dextran T40 or 8% agarose/4% dextran T150 showed a higher separation resolution for proteins within range of low molecular weight. Furthermore, the mechanical strength of this composite microsphere was improved by adjusting its composition. Atomic force microscope (AFM) results showed that pores were distributed evenly on both the surface and the inner part of microspheres, beneficial for the passage of biomolecules. These novel uniform polysaccharide composite microspheres have great potential for high-resolution bioseparation. Graphical abstract ᅟ.

Interfacial Behavior of Aqueous Two-Phase Systems Based on Linear and Hyperbranched Polymers

In this work, the interfacial behavior of two different aqueous two-phase systems (ATPSs) was analyzed. One ATPS is formed by the dissolution of polyethylene glycol (PEG) and dextran T40 in water, and the second ATPS is formed by a hyperbranched polyesteramide (HB) and dextran T40. The interfacial behavior of both ATPSs was investigated experimentally and theoretically. As a thermodynamic model, the lattice cluster theory combined with a lattice Wertheim model was used. This thermodynamic model was combined with density gradient theory to model the interfacial properties. It was found that the interfacial tension, which was measured by the spinning drop method, of the ATPS containing the HB was lower than the interfacial tension of the ATPS containing the PEG. Moreover, the mass transfer of the phase forming components across the interface was measured and modeled. To measure the mass transfer, a Nitsch cell was used. The mass transfer was modeled by the instationary density gradient theory. It was found ...

Effects of dextran with different molecular weights on the quality of wheat sourdough breads

This research aimed at investigating the effects of different weight-average molecular weights (Mw: T10, T70, T250, T750, T2000) of dextran (α-(1 → 6)-linked linear backbone, α-(1 → 3)-linked branching) on wheat sourdough bread qualities. Texture analyzer showed that dextran contributed to a significant inhibition of bread staling, particularly dextran T2000. Pasting profiles (Rapid visco-analysis) and steady rheological properties (steady shear measurements) of samples indicated that dextran T2000 suppressed the swelling and gelatinization of wheat starch granules and bound a great amount of water, thus retarding the aging process. Dextran T2000 markedly improved the elastic properties of sourdough-containing dough. Wheat sourdough breads containing dextran T10 exhibited unexpected less firm crumb structure. The improvement of bread qualities was a function of the Mw of dextran. Dextran with high Mw values has the potential for improving the quality of wheat sourdough breads, especially extending shelf life.

Optimized endodextranase-epoxy CIM ® disk reactor for the continuous production of molecular weight-controlled prebiotic isomalto-oligosaccharides

An epoxy-activated monolithic Convective Interaction Media (CIM®) disk was used for the immobilization of endodextranase D8144 from Penicillium sp. (EC 3.2.1.11) in order to produce on-line isomalto-oligosaccharides (IMOs) from Dextran T40. Enzymatic parameters, molecular weight of IMOs and performance of the IMmobilized Enzymes Reactor (IMER) were investigated. The immobilization yield of enzymes was about 45.3% (w/w), and the real specific activity close to 3.26 U mg−1. The Km values did not significantly change between free (12.8 g L−1) and immobilized enzymes (14.2 g L−1), due to the absence of diffusional limitation. The IMER system presented more than 80% of its residual activity after 5000 column volumes, highlighting the high stability of the immobilized endodextranases. Response surface methodology was used to enhance the performance of the IMER. Depending on dextran concentrations and flow rates, specific patterns of IMOs distributions were observed during the enzymatic hydrolysis. Finally, prebiotic activity was also investigated on IMOs produced by medium conditions (flow rate 0.3 mL min−1 and dextran concentrations 4% w/w) against Lactobacillus rhamnosus GG (ATCC 53103). Their scores were at least as good as two commercialized fructo-oligosaccharides (FOS), Fibrulose® F97 and Orafti® P95.

Ibuprofen and acetylsalicylic acid loaded electrospun PVP-dextran nanofiber mats for biomedical applications

The aim of this work is to investigate the suitability of electrospinning for biomedical applications and to produce fast-dissolving drug delivery through uniform dextran nanofiber nonwoven maps. To prepare oral fast-dissolving drug delivery nonwoven maps via electrospinning technology, ibuprofen (Ibu) and acetylsalicylic acid (ASA) as the model drugs, and polyvinylpyrrolidone (PVP), dextran T10 (Dext T10) and dextran T40 (Dext T40) as the filament-forming polymer and drug carrier were selected. Morphology of nanofiber samples was characterized by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). SEM images showed homogeneous dispersion of drugs into the polymer blends. The structure analysis made by attenuated total reflectance/Fourier transform infrared spectroscopy suggested that PVP/dextran and drug blended very well in the nanofibers. The amount of ibuprofen and acetylsalicylic acid in a nanofiber samples was determined using reverse-phase high-performance liquid chromatography. The results showed that the ibuprofen content in PVP/Dext T40-Ibu and PVP/Dext T10-Ibu nanofiber samples (431.7 ± 39.7 and 528.3 ± 24.7 µg/mL, respectively) is significantly higher than acetylsalicylic acid content in PVP/Dext T40-ASA and PVP/Dext T10-ASA nanofiber samples (145.5 ± 5.6 and 168.3 ± 7.3 µg/mL, respectively). Antibacterial properties of the fiber samples containing drug against Gram-negative (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922) and Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633) were examined. The PVP-drug containing nanofibers resulted in a superior antibacterial activity than PVP/dextran-drug containing nanofibers. PVP/Dext T10 and PVP/Dext T40 nanofibers have the potential to be used as solid dispersions to improve the dissolution profiles of poorly water-soluble drugs and/or fast disintegrating drug delivery systems.

Chiral separation of mandelic acid enantiomers using an aqueous two-phase system based on a thermo-sensitive polymer and dextran

In this study, a thermo-sensitive polymer Poly(MAH-β-CD-co-NIPAAm) was synthesized by the copolymerization of N-isopropylazylamide (NIPAAm) with the maleic anhydride (MAH) modified β-cyclodextrin (β-CD). This polymer was both used as chiral selector and phase-forming component of aqueous two-phase system (ATPS). ATPS formed by Poly(MAH-β-CD-co-NIPAAm) and dextran T40 was used for chiral separation of mandelic acid (MA) enantiomers. The influencing parameters of the distribution behavior of MA were studied, viz. concentration of thermo-sensitive polymer, pH, operational temperature, and initial MA concentration. The results showed that this chiral selector preferentially recognizes the (S)-enantiomer rather than the (R)-enantiomer, the maximum separation factor (α) can reach to 1.27 under the optimum conditions. The thermo-sensitive polymer can be recycled by heating and centrifugation after enantioseparation. This ATPS is a simple, green and economical approach for the chiral separation of MA and other chiral enantiomers.

Development of A Monoclonal Antibody‐Based Competitive Elisa Method for Quantitative Detection of Dextran

AbstractTo solve processing problems caused by bacterial activity in sugar industry, a sensitive method for dextran detection is expected. In this study, monoclonal antibodies (mAbs) against dextran were prepared using dextran T40 conjugated with bovine serum albumin as immunogens. Basing on the mAbs, a competitive enzyme‐linked immunosorbent assay (ELISA) method to measure dextran quantitatively was developed. Results demonstrated that this competitive ELISA method had a calibration curve with correlation coefficient of 0.9986, IC50 value of 204.2 ng/mL and detection value ranging from 26.3 ng/mL to 1174.9 ng/mL. In addition, cross‐reaction assay suggested the method had no significant cross‐reaction with dextran‐related substances such as β‐glucan, starch, sucrose, sugar and glucose. Besides, spike recovery assay indicated this quantitative method for dextran detection had a perfect accuracy.Practical ApplicationsWith wide detection range, high specificity and good calibration curve, this developed competitive ELISA method will be reliable to detect dextran quantitatively in sugar industry, and even may be commercially applied into kit development.

Inhaled PYY(3–36) dry-powder formulation for appetite suppression

Objective: Peptide YY3–36 [PYY(3–36)] has shown efficacy in appetite suppression when dosed by injection modalities (intraperitoneal (IP)/subcutaneous). Transitioning to needle-free delivery, towards inhalation, often utilizes systemic pharmacokinetics as a key endpoint to compare different delivery methods and doses. Systemic pharmacokinetics were evaluated for PYY3–36 when delivered by IP, subcutaneous, and inhalation, the systemic pharmacokinetics were then used to select doses in an appetite suppression pharmacodynamic study.Methods: Dry-powder formulations were manufactured by spray drying and delivered to mice via nose only inhalation. The systemic plasma, lung tissue, and bronchoalveolar lavage fluid pharmacokinetics of different inhalation doses of PYY(3–36) were compared to IP and subcutaneous efficacious doses. Based on these pharmacokinetic data, inhalation doses of 70:30 PYY(3–36):Dextran T10 were evaluated in a mouse model of appetite suppression and compared to IP and subcutaneous data.Results: Inhalation pharmacokinetic studies showed that plasma exposure was similar for a 2 × higher inhalation dose when compared to subcutaneous and IP delivery. Inhalation doses of 0.22 and 0.65 mg/kg were for efficacy studies. The results showed a dose-dependent (not dose proportional) decrease in food consumption over 4 h, which is similar to IP and subcutaneous delivery routes.Conclusions: The pharmacokinetic and pharmacodynamics results substantiate the ability of pharmacokinetic data to inform pharmacodynamics dose selection for inhalation delivery of the peptide PYY(3–36). Additionally, engineered PYY(3–36):Dextran T10 particles delivered to the respiratory tract show promise as a non-invasive therapeutic for appetite suppression.

Preparation and Characteristic of Dextran-BSA Antibody and Establishment of its ELISA Immunoassay

The enzyme-linked immunosorbent assay (ELISA) is a potential tool for the determination of dextran. In this study, dextran neoglycoprotein antigens were prepared by Reductive Amination method, and were confirmed by SDS-PAGE and free amino detection. The impact factors such as different oxidation degree of dextran, the conjugate reaction time to BSA were investigated. The best preparation conditions were obtained (ndextran/noxidant of NaIO4 = 1/120, the reaction time of 24 h), and the antigen with best combination with standard was obtained. The antigens interacted with standard antibody and were evaluated through ELISA. The immunogen was immunized with white rabbits to obtained antibody, respectively. A general and broad class-specific ELISA immunoassay was developed for dextran detection according to ELISA theory. The optimized conditions of assay used coating antigen at 10 μg/mL, reaction time of antibody and rabbit-anti-bovine IgG in 45 min, blocking reagents with 5% calf serum. The developed ELISA detection method with good linear and accuracy was put to use for quantitative analysis of dextran T40 in commercial sugarpractical for detection of dextran.

Development of monoclonal antibody-based sandwich ELISA for detection of dextran.

Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9 ng/mL and 7.8-500 ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.