This study aims to prepare vitexin albumin nanoparticles(VT-BSA-NPs) to alleviate the low bioavailability of vitexin(VT) in vivo due to its poor water solubility. VT micro powders were prepared by the antisolvent crystallization method, and the morphology, size, and physicochemical properties of VT micro powders were studied. The results showed that the VT micro powder had a particle size of(187.13±7.15) nm, an approximate spherical morphology, and a uniform size distribution. Compared with VT, the chemical structure of VT micro powders has not changed. VT-BSA-NPs were prepared from VT micro powders by desolvation-crosslinking curing method. The preparation process was screened by single factor test and orthogonal test, and the quality evaluation of the optimal prescription particle size, PDI, Zeta potential, EE, and morphology was performed. The results showed that the average particle size of VT-BSA-NPs was(124.33±0.47) nm; the PDI was 0.184±0.012; the Zeta potential was(-48.83±2.20) mV, and the encapsulation rate was 83.43%±0.39%, all of which met the formulation-related requirements. The morphological results showed that the VT-BSA-NPs were approximately spherical in appearance, regular in shape, and without adhesion on the surface. In vitro release results showed a significantly reduced release rate of VT-BSA-NPs compared with VT, indicating a good sustained release effect. LC-MS/MS was used to establish an analytical method for in vivo analysis of VT and study the plasma pharmacokinetics of VT-BSA-NPs in rats. The results showed that the specificity of the analytical method was good, and the extraction recovery was more than 90%. Compared with VT and VT micro powders, VT-BSA-NPs could significantly increase AUC, MRT, and t_(1/2), which was beneficial to improve the bioavailability of VT.
Rats ; Animals ; Serum Albumin, Bovine/chemistry* ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Nanoparticles/chemistry* ; Particle Size ; Drug Carriers/chemistry*

Small molecules with physiological or pharmacological activities need to interact with biological macromolecules in order to function in the body. As the protein with the highest proportion of plasma protein,serum albumin is the main protein binding to various endogenous or exogenous small molecules. Serum albumin interacts with small molecules in a reversible non-covalent manner and transports small molecules to target sites. Bovine serum albumin( BSA) is an ideal target protein for drug research because of its low cost and high homology with human serum albumin. The research on the interaction between drugs and BSA has become a hotspot in the fields of pharmacy,medicine,biology and chemistry. In this research,molecular docking method was used to study the interaction between three small ginsenosides with high pharmacological value( Rg_1,Rb_1,Ro) and bovine serum albumin( BSA),and the binding mode information of three ginsenosides interacting with BSA was obtained. The results of molecular docking showed that ginsenosides and amino acid residues in the active pocket of proteins could be combined by hydrophobic action,hydrogen bonding and electrostatic action. The interaction between small ginsenosides and bovine serum albumin is not the only form,and their interaction has many forms of force. The interaction between these molecules and various weak forces is the key factor for the stability of the complex. The results of this study can provide the structural information of computer simulation for the determination of the interaction patterns between active components and proteins of ginseng.
Animals ; Binding Sites ; Cattle ; Computer Simulation ; Ginsenosides ; chemistry ; Molecular Docking Simulation ; Protein Binding ; Serum Albumin, Bovine ; chemistry ; Spectrometry, Fluorescence ; Thermodynamics

In this work, a novel conjugate of ractopamine and bovine serum albumin (RAC-BSA) has been developed via the Mannich reaction, with a mole coupling ratio for RAC-BSA of 9:1. The proposed conjugation method provides a simple and one-step method with the use of fewer reagents compared with other conjugation methods for competitive immunoassays. RAC-BSA conjugation was used to fabricate a competitive lateral flow strip test for RAC detection in animal feed. For sample preparation, RAC was spiked in swine feed purchased from the local markets in Thailand, and methanol and running buffer at a volume ratio of 10:90 was used as extraction buffer. The procedures for sample preparation were completed within 25 min. Under optimal conditions, the limit of detection (LOD), assessed by the naked eye within 5 min, was found to be 1 ng/g. A semi-quantitative analysis was also conducted using a smart phone and computer software, with a linearity of 0.075-0.750 ng/g, calculated LOD of 0.10 ng/g, calculated limit of quantitation of 0.33 ng/g, and good correlation of 0.992. The recoveries were found in the range of 96.4%-103.7% with a relative standard deviation of 2.5%-3.6% for intra- and inter-assays. Comparison of the results obtained by the strip test with those obtained by enzyme-linked immunosorbent assay had a good agreement in terms of accuracy. Furthermore, this strip test exhibited highly specific RAC detection without cross reactivity with related compounds. Therefore, the RAC-BSA conjugation via the Mannich reaction can be accepted as a one-step and easy conjugation method and applied to the competitive lateral flow strip test.
Animal Feed/analysis* ; Animals ; Cross Reactions ; Enzyme-Linked Immunosorbent Assay/methods* ; Limit of Detection ; Phenethylamines/chemistry* ; Reagent Strips ; Serum Albumin, Bovine/chemistry* ; Swine

OBJECTIVETo investigate the effect of epigallocatechin-3-gallate (EGCG) on biomodification of demineralized dentine substrate, in its permeability, hydrophobicity, and inhibition ability to collagen enzymatic degradation.

METHODSThe dentine substrates were treated with simulated pulpal pressure created by mixtures of 0.02%, 0.1% EGCG/bovine serum albumin (BSA) in acidic environment (pH4.4) for 48 h. A fluid-transport model was used to measure the fluid permeability through demineralized dentine substrate. Positive replicas of dentine substrate were fabricated before and after being subjected to acidic environment for scanning electron microscope (SEM) examination. The blank group contained no EGCG and the positive group were treated with Gluma desensitizer. Static contact angle measurements on demineralized dentin and 0.1% EGCG primed dentin were performed by contact angle analyzer. The priming time were 60 s, 120 s, 0.5 h, 1 h. Dentine specimens bonded with Adper single bond 2 were subjected to 100 mg/L collagenase and observed under SEM. Resin-bonded specimens (with 0.02%, 0.1%, 0.5% EGCG priming, or without EGCG priming) were created for micro-tensile bond strength evaluation (MTBS). Resin-bonded specimens after thermol cycling were created for MTBS evaluation.

RESULTSThe fluid permeability in the blank control group increased ([151.3±22.3]%), the fluid permeability in 0.1% EGCG/BSA group decreased ([23.7±6.3]%). Compared to the blank control group, the contact angle of 120 s, 0.5 h, 1 h groups increased by 31.0%, 53.5%, 57.8% in deep dentin and 37.4%, 59.3%, 62.4% in shallow dentin. The SEM examination showed that 0.1% and 0.5% EGCG priming for 120 s significantly increased dentin collagen's resistance to collagenase. The immediate MTBS of 0.1% and 0.5% EGCG groups were (29.4±4.8) and (19.8± 4.9) MPa. After thermol cycling, the MTBS of 0.1% and 0.5% EGCG groups were (19.9±5.1) and (15.3± 6.3) MPa.

CONCLUSIONSUnder acidic environment (pH4.4), the 0.1% EGCG can reduce dentine permeability under acidic environment. The 0.1% EGCG can increase hydrophobicity of dentin substrate, and strengthen dentin substrate's resistance to collagenase hydrolysis, thus increased the resin-dentin bonding durability.

Acid Etching, Dental ; Catechin ; analogs & derivatives ; pharmacology ; Collagen ; chemistry ; drug effects ; Collagenases ; pharmacology ; Composite Resins ; Dental Bonding ; Dental Cements ; Dental Pulp ; Dentin ; chemistry ; drug effects ; Dentin Permeability ; drug effects ; Dentin-Bonding Agents ; Glutaral ; pharmacology ; Hydrogen-Ion Concentration ; Hydrolysis ; Methacrylates ; pharmacology ; Microscopy, Electron, Scanning ; Pressure ; Resin Cements ; Serum Albumin, Bovine ; pharmacology ; Tensile Strength ; Time Factors

In this paper, the new carbon nanotube modified glassy carbon electrode (F-CNTs/GCE) was prepared to establish a new method for studying the molecular interaction mechanism between baicalin metal complexes (BMC) and bovine serum album (BSA), and the principle of this method was discussed deeply. Under the physiological condition, the thermodynamics and kinetics properties of interaction between BMC and BSA were studied by cyclic voltammetry (CV) to inference their molecular effective mechanism. The results show that the presence of F-CNTs can accelerate the electron transfer, and better response signal was showed in the BMC/BMC-BSA system. The detection of interaction of BMC-BSA used new method show that BMC-BSA generates stable thermodynamically non-covalent compounds, and the obtained average binding sites of BMC-BSA were 1.7; the number of electron transfer in BMC/BMC-BSA reaction process was 2, and non electroactive supramolecular compounds of BMC-BSA were generated by this interacting reaction. The relevant research work provides a new way to study the molecular mechanism for the interaction of drugs with protein, and with a certain reference value for discussion on the non covalent interactions.
Animals ; Cattle ; Coordination Complexes ; chemistry ; Electrodes ; Flavonoids ; chemistry ; Kinetics ; Nanotubes, Carbon ; Serum Albumin, Bovine ; chemistry ; Thermodynamics

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.
Animals ; Antibodies ; immunology ; Antigens ; chemistry ; immunology ; Immunoassay ; Iridoid Glucosides ; chemistry ; immunology ; Male ; Medicine, Chinese Traditional ; Mice ; Mice, Inbred BALB C ; Serum Albumin, Bovine ; chemistry ; immunology

OBJECTIVE: To explore the interaction between cefdinir (CE) and bovine serum albumin (BSA) by fluorescence and ultraviolet-visible absorption spectrometry.
 METHODS: Under the optimal conditions, the interaction between CE and BSA was investigated by fluorescence and ultraviolet-visible absorption spectrometry.
 RESULTS: CE could quench (static quenching) the intrinsic fluorescence of BSA by forming the CE-BSA complex. The main binding forces were considered as hydrogen bonds and Van der Waals forces based on the calculated values of the thermodynamic parameter. The process of binding was spontaneous because Gibbs free energy change was negative. The primary binding site for CE was located at sub-domain II of BSA. The values of Hill's coefficients were less than 1, indicating a negative cooperative effect. Synchronous fluorescence spectra showed that the conjugation reaction between CE and BSA did not affect the conformation of BSA, and the binding site was close to the tyrosine residue.
 CONCLUSION This test provides a theoretical basis for revealing the pharmacokinetic issue and the development for new drugs.
Binding Sites ; Cefdinir ; Cephalosporins ; chemistry ; Serum Albumin, Bovine ; chemistry ; Spectrophotometry, Ultraviolet ; Thermodynamics

Oxidation method with sodium iodide was used to synthesize immunogenic antigen (PF-BSA) and coating antigen (PF-OVA) of paeoniflorin. UV spectroscopy showed that paeoniflorin was successfully conjugated with BSA and OVA. After immunized by PF-BSA, the mice can produce anti-paeoniflorin antibodies specifically. The ELISA test results showed the high titer (1:12 800) and specificity (IC50 = 0.791 mg x L(-1)) of the antiserum from mice injected with PF-BSA. Also, the antiserum showed low cross activities against nine traditional Chinese medicine (TCM) of small molecules. These artificial antigens were successfully synthesized and the anti-paeoniflorin antibody well prepared, which provides the experimental basis for the further study of ELISA and its kit.
Animals ; Antibodies ; analysis ; Antigens ; chemistry ; immunology ; Drugs, Chinese Herbal ; chemistry ; Enzyme-Linked Immunosorbent Assay ; Glucosides ; chemistry ; immunology ; Male ; Mice ; Mice, Inbred BALB C ; Monoterpenes ; chemistry ; immunology ; Serum Albumin, Bovine ; chemistry ; immunology

Animals ; Cattle ; Cell Line ; Electrophoresis, Polyacrylamide Gel ; Fluorescent Dyes ; chemistry ; Malondialdehyde ; chemistry ; Mice ; Microscopy, Confocal ; Serum Albumin, Bovine ; analysis ; chemistry ; metabolism ; Ultraviolet Rays

OBJECTIVESynthesis and identification of complete antigen of rutin, the traditional Chinese medicine active ingredient, and develop rapid detection of rutin using enzyme-linked immunoassay method (ELISA). Immunogenicity of the complete antigen was also studied.

METHODPrepare the complete antigen by sodium periodate solution and identified by UV scanning and SDS-PAGE test. Male New Zealand white rabbits were immunized by the antigen to obtain the antiserum.

RESULTThe results of UV analysis showed that the coupling ratio of complete antigen is 13: 1. SDS-PAGE display of the artificial antigen was delayed compared with bovine serum protein. The titer of rutin antibody is 1:4 000. The sensitivity of IC50 was 5.37 mg x L(-1), the lowest detection limit was 1 mg x L(-1), the average recovery was 102%, the intra and interspecific RSD were less than 10%, cross-reactivity rate of antibodies and other analogs were less than 1%.

CONCLUSIONRutin complete antigen was synthesized successfully, and the rapid detection of rutin by ELISA method was successfully established.

Animals ; Antibody Specificity ; immunology ; Antigens ; immunology ; Cattle ; Cross Reactions ; immunology ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Immune Sera ; immunology ; Immunization ; Male ; Periodic Acid ; chemistry ; Rabbits ; Rutin ; chemical synthesis ; immunology ; Serum Albumin, Bovine ; immunology ; Solutions ; chemistry