Biomedical subjects

Bin Deng

Publications and source records attributed to Bin Deng.

22 records · Page 2Linked to original sources

PubMed2002

New quaternary bismuth sulfides: syntheses, structures, and band structures of AMBiS4 (A = Rb, Cs; M = Si, Ge).

Four new compounds, RbSiBiS(4), RbGeBiS(4), CsSiBiS(4), and CsGeBiS(4), have been synthesized by means of the reactive flux method. The isostructural compounds RbSiBiS(4), RbGeBiS(4), and CsGeBiS(4) crystallize in space group P2(1)/c of the monoclinic system with four formula units in cells of dimensions at 153 K of a = 6.4714(4) A, b = 6.7999(4) A, c = 17.9058(11) A, and beta = 108.856(1) degrees for RbSiBiS(4), a = 6.5864(4) A, b = 6.8559(4) A, c = 17.9810(12) A, and beta = 109.075(1) degrees for RbGeBiS(4), and a = 6.5474(4) A, b = 6.9282(4) A, c = 18.8875(11) A, and beta = 110.173(1) degrees for CsGeBiS(4). CsSiBiS(4) crystallizes in a different structure type in space group P2(1)/c of the monoclinic system with four formula units in a cell of dimensions at 153 K of a = 9.3351(7) A, b = 6.9313(5) A, c = 12.8115(10) A, and beta = 109.096(1) degrees. The two structure types are closely related and consist of [MBiS(4)(-)] (M = Si, Ge) layers separated by bicapped trigonal-prismatically coordinated alkali-metal atoms. In each, the M atom is coordinated to a tetrahedron of four S atoms and the Bi atom is coordinated to seven S atoms comprising five close S atoms at the corners of a square pyramid with Bi near the center of the basal plane and the sixth and seventh S atoms further away to complete a distorted monocapped trigonal prism. The optical band gaps of 2.23 eV for RbGeBiS(4) and 2.28 eV for CsGeBiS(4) were deduced from their diffuse reflectance spectra. From a band structure calculation, the optical absorption for RbGeBiS(4) originates from the [GeBiS(4)(-)] layer. The Ge 4p orbitals, Bi 6p orbitals, and S 3p orbitals are highly hybridized.

Journal Article↗

PubMed2002

New layered rubidium rare-earth selenides: syntheses, structures, physical properties, and electronic structures for RbLnSe(2).

The compounds RbLnSe(2) (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Ho, Er, Lu) have been synthesized by means of the reactive flux method at 1173 K. These isostructural compounds, which have the alpha-NaFeO(2) structure type, crystallize with three formula units in space group D(3d)(5)-R(-)3m of the trigonal system in cells at T = 153 K of dimensions (a, c in A) La, 4.4313(4), 23.710(3); Ce, 4.3873(3), 23.656(3); Pr, 4.3524(11), 23.655(7); Nd, 4.3231(5), 23.670(4); Sm, 4.2799(4), 23.647(3); Gd, 4.2473(7), 23.689(5); Tb, 4.2197(4), 23.631(3); Ho, 4.1869(6), 23.652(5); Er, 4.1541(8), 23.576(7); Lu, 4.1294(6), 23.614(5). The structure consists of close-packed Se layers in a pseudocubic structure distorted along [111]. The Rb and Ln atoms occupy distorted octahedral sites in alternating layers. The Rb-centered octahedra share edges with the Ln-centered octahedra between layers. Within a given layer, both the Rb-centered and Ln-centered octahedra share edges with themselves. RbTbSe(2) and RbErSe(2) exhibit Curie-Weiss paramagnetism between 5 and 300 K, and RbCeSe(2) exhibits Curie-Weiss paramagnetism between 100 and 300 K. The optical transitions for RbCeSe(2), RbTbSe(2), and RbErSe(2) are in the 2.0-2.2 eV region of the spectrum, both from diffuse reflectance spectra and from first-principles calculations. These calculations also provide insight into the electronic structures and chemical bonding in RbLnSe(2). A quadratic fit for the lanthanide contraction of the Ln-Se distance is superior to the linear one only if the closed-shell atoms La and Lu are included.

Journal Article↗

PubMed2002

Rapid quantitative determination and assessment of insulin in oil formulation by micellar electrokinetic capillary chromatography.

A rapid, simple and precise micellar electrokinetic capillary chromatrography (MEKC) with diode array detector had been developed to the determination of insulin in oil formulation. As the micelle-forming ampholytic surfactant, Labrasol was chosen for the separation and analysis of the hydrophobic insulin in oil formulation in this experiment. A buffer containing 10 mmol/ml Tris-HCl plus 10% acetonitrile (ACN) at pH 8.2 was used for running buffer. Samples and tested samples were successfully separated during 8 min with a good linear range(r>0.99) and a concentration detection limit of 0.01 mg/ml. Furthermore, quantitative determinations of insulin in oil formulation had been described and assessed after handled with different pre-treatment conditions to reveal the effect of pH, temperature and tryptic digestion.

Chemistry, Pharmaceutical↗

PubMedDate not supplied

Monitoring the unfolding and refolding of creatine kinase by capillary zone electrophoresis.

Creatine kinase (ATP: creatine N-phosphotransferase; EC 2.7.3.2) plays a key role in the energy transport, muscle contraction, and reproduction of adenosine triphosphate (ATP). The activity of the enzyme is dependent on the correct folding of the peptide. We observed the unfolding and refolding processes of the creatine kinase of rabbit muscle, and concluded that traditional electrophoresis technology is unsuitable for the transient folding intermediates formed during protein unfolding and refolding. Capillary zone electrophoresis with diode array detection was used to monitor the unfolding and refolding of rabbit creatine kinase under different pretreatments and experimental conditions. This technique provides a simple, sensitive, and rapid approach to protein unfolding and refolding.

Animals↗