Biomedical subjects

Bing Zhao

Publications and source records attributed to Bing Zhao.

At least 37 records · Page 2Linked to original sources

PubMed2006

[Study on the oxidation of solutions of aniline and phenol on Ti/SnO2-Sb2O5 electrode by UV-Vis spectroscopy and HPLC].

The electrocatalytic oxidation and degradation of phenol and aniline were studied at Ti/SnO2-Sb2O5 electrode by UV-Vis spectroscopy and high performance liquid chromatography (HPLC). It is shown that hydroquinone, benzoquinone and maleic acid are the same intermediates and products during oxidation of both aniline and phenol. This indicates that the oxidation of the two compounds probably has the same degradation routes. The electropolymerization of anilines results in different oxidation and degradation course of aniline and phenol.

English Abstract↗

PubMed2006

[Construction and expression of a prokaryotic expression plasmid of idiotypic vaccine against B cell lymphoma: encoding the fusion genes of single-chain variable fragment and MCP-3].

The aim was to construct a prokaryotic expression plasmid encoding the fusion gene of single-chain variable fragment and monocyte chemotactic protein-3 (MCP-3). The cDNAs of immunoglobulin (Ig) VH and Ig VL were amplified by RT-PCR and assembled into the single-chain variable fragment (scFv) by recombinant PCR method. The cDNAs of Ig VH and Ig VL were connected by a (Gly4Ser)3 linker. Then, the fragments of scFv and MCP-3 were connected with a NDAQAPKS spacer, using recombinant PCR method again. The results indicated that the fusion gene of scFv-MCP-3 were constructed correctly and cloned into the prokaryotic expression plasmid successfully identified by sequencing and restriction endonucleases examination. Finally, the fusion protein was expressed in E coli DH5alpha under induction by arabinose. And the fusion protein was 65 kD and account for 30% of the total protein of the bacteria. In conclusion, a prokaryotic plasmid, encoding the fusion gene of single-chain variable fragment with MCP-3 and expressing idiotype protein vaccination against B cell lymphoma, was constructed correctly.

Amino Acid Sequence↗

PubMed2005

Optical properties of Ag/CdTe nanocomposite self-organized by electrostatic interaction.

Ag/CdTe nanocomposite was prepared via self-organization process by electrostatic interaction between positively charged CdTe quantum dots and negatively charged Ag nanoparticles and examined with respect to their optical properties. The positively charged CdTe quantum dots and negatively charged Ag nanoparticles were synthesized separately by modifying nanoparticles surface with cationic and anionic thiol compounds, respectively. The result showed that the mixing ratio of Ag nanoparticles to CdTe quantum dots is an important parameter for controlling resulting composites. The resulting solution is optically transparent if one component is in excess. Photoluminescence of CdTe quantum dots undergoes considerably quenching if CdTe nanocrystals are in excess and SERS spectra of BVPP absorbed on Ag colloid became stronger if Ag nanoparticles are in excess. Nevertheless, while the ratio is approximately 1, micrometer-sized solid composite is obtained with the elapse of 1h after mixing. SERS spectra for solid composite only exhibit the signals of the CdS nanocrystal which reflected that prolonged refluxing during the synthesis leads to a partial hydrolysis of the thiols and to the incorporation of the sulfur from the thiol molecules into the the growing nanoparticles to form mixed CdTe(S) nanocrystal, similar to CdTe/CdS core/shell structure. From the results, we conclude that optical properties of Ag/CdTe are dependent on the mixing ratio of both nanoparticles.

Cadmium Compounds↗

PubMed2005

Surface-enhanced Raman activity and stability study of silver films prepared by reduction of Ag+ ions in N,N-dimethylformamide.

A new SERS-active silver film prepared by directly depositing silver nanoparticles on glass is reported. The spontaneous reduction of Ag+ ions in N,N-dimethylformamide (DMF) (in the absence of a protecting agent) leads to the deposition of silver nanoparticles on clean glass surfaces in contact with the solution. The observed optical micrographs and AFM images show that the arrangement of the nanoparticles is inhomogeneous and the particles appear to be closely packed. These films are shown to be excellent substrates for SERS measurements, demonstrating significant enhancement, good stability, and trace detection capability. The SERS enhancement of the silver films with different deposition times was compared and found that the 8-h film gives the largest enhancement ability with an enhancement factor estimated at about 10(9). It is also found that the silver films stored for 80 days in air show no significant degradation in their sensitivity.

Dimethylformamide↗

PubMed2005

Serotonergic reticular formation cells in Rana pipiens: categorization, development, and tectal projections.

The reticular formation contributes serotonin to many brain regions, including the optic tectum. We examined the organization and development of its serotonergic neurons in the leopard frog. Serotonin-immunoreactive (5-HT-ir) cells in adult frogs were organized into 10 distinct populations that were identified on the basis of their location and cellular morphology. Populations ranged in size from 16 to 2,066 cells and sometimes spanned more than one previously identified nuclear region. Four of the ten populations were absent in tadpoles. The remaining populations, though present, had two contrasting patterns of development. Half of the populations were established early and showed little change in numbers during tadpole stages but increased in size in juvenile and adult frogs. The other half increased dramatically during tadpole stages but failed to add many more cells in juveniles and adults. Three populations provided 90% of the serotonergic projections from the reticular region to the adult optic tectum. These projections were established early in development and likely originated from the dorsal raphe, median raphe, raphe pontis, raphe magnus, and reticularis pontis oralis. Termination sites were located in midtectal layers and were not topographically organized. We conclude that serotonergic cells within the reticular formation of the leopard frog have an organization similar to that found in mammals, that the overall increase in numbers of these cells is attributable to growth in different cell populations at different stages, and that input from this region changes activity levels in the optic tectum in a global rather than a site-specific manner.

Animals↗

PubMed2005

The molecular structure and orientation of antiferroelectric liquid crystal using the density-functional theory and two-dimensional correlation-polarized infrared spectroscopy.

The structure and vibrational frequencies of the chiral antiferroelectric liquid-crystal molecule, 4-(1-methyheptyloxycarbonyl) phenyl-4-(4'-octyloxy) benzoate (MHOCPOOB), have been calculated using the density-functional theory (DFT) with the Becke-3 Lee-Yang-Parr/6-31G(d,p) level. The observed vibrational spectra have been resolved and assigned in detail by comparison to the computed values. The results indicate that the computed and observed spectra are in good agreement with each other. The stable molecular structure obtained with the DFT theory shows that the two hydrocarbon chains are all-trans zigzag conformer and nearly perpendicular to each other. The orientation of the mesogen part and the hydrocarbon chains for MHOCPOOB in the Sm-C*A phase are investigated by employing the polarization-angle-dependent infrared spectra in the electric-field induced and the two-dimensional correlation spectroscopy. After combining the experimental and theoretical results, it can be concluded that the azimuth of the achiral and chiral chains is opposite to each other, the orientation of the achiral chain is almost the same direction as the mesogen core, and the orientation of the chiral chain is nearly perpendicular to the mesogen part. The achiral and chiral CH2 chains are both a probable all-trans zigzag conformer.

Journal Article↗

PubMed2005

Effects of a central metal on the organization of 5,10,15,20-tetra-(p-chlorophenyl)-rare earth porphyrin hydroxyl compound at the air/water interface and in Langmuir-Blodgett films.

Langmuir monolayers and Langmuir-Blodgett (LB) films of 5,10,15,20-tetra-(p-chlorophenyl) terbium/gadolinium porphyrin hydroxyl compound (TbOH and GdOH) and their mixtures with stearic acid (SA) in a molar ratio of 1:1 were investigated by Brewster angle microscopy (BAM), ultraviolet-visible (UV-vis), and infrared (IR) spectroscopy and atomic force microscopy (AFM). pi-A isotherms showed that well-defined Langmuir monolayers were formed at an air/water interface for the porphyrins and their mixture with SA. The BAM observations suggest that the pi-pi interaction between the GdOH molecules is stronger than that between the TbOH molecules. This result can be further confirmed by the AFM measurements. After the introduction of SA, the pi-pi interaction between the TbOH molecules is broken and thus two phases formed in the mixed LB film. However, it cannot break the stronger pi-pi interaction between the GdOH molecules. Therefore, no phase separation is observed in the GdOH/SA LB film. IR reflection-absorption (RA) spectra showed that the COOH groups of SA are partly converted to COO(-) groups, suggesting that there is an interaction between MOH and SA in the films. This interaction leads the benzene rings of TbOH to rotate toward parallel to the substrate and those of GdOH to rotate toward perpendicular to the substrate. All these results have demonstrated that the central metal ions have great effects on the organization and formation of the films.

Journal Article↗

PubMed2005

A framework to sub-type HLA supertypes.

The human leukocyte antigen (HLA) alleles are extremely polymorphic among ethnic population and the peptide binding specificity varies for different alleles in a combinatorial manner. However, it has been suggested that majority of alleles can be covered within few HLA supertypes, where different members of a supertype bind similar peptides, yet exhibiting distinct repertoires. Since the overlap between different members of a supertype appears to be extensive, it is crucial to develop a framework for grouping alleles into supertypes just from sequence information. In this report, we define sub supertypes, where members show functional overlap with identical repertoire, and describe a strategy to group HLA-A, B and C alleles into different categories of sub supertypes. The strategy grouped 47% of 295 A alleles, 44% of 540 B alleles and 35% of 156 C alleles to just 36, 71 and 18 groups, respectively. The grouping is moderately validated using available binding data. However, the validation is limited due to lack of binding data. Hence, the data presented in this article serve as a framework to test specific functional overlap between alleles. The grouping of HLA alleles into different categories of sub supertypes has profound use in the understanding of antigenic peptide selection, degeneration and discrimination during T-cell mediated immune response. A complete knowledge of this phenomenon finds utility in epitope design for the development of HLA based vaccines and immuno-therapeutics.

Alleles↗

PubMed2005

Proteome investigation of the global regulatory role of sigma 54 in response to gentisate induction in Pseudomonas alcaligenes NCIMB 9867.

Pseudomonas alcaligenes NCIMB 9867 (strain P25X) utilizes the gentisate pathway for the degradation of aromatic hydrocarbons. The gene encoding the alternative sigma (sigma) factor sigma(54), rpoN, was cloned from strain P25X and a rpoN knock-out strain, designated G54, was constructed by insertional inactivation with a kanamycin resistance gene cassette. The role of sigma(54) in the physiological response of P. alcaligenes P25X to gentisate induction was assessed by comparing the global protein expression profiles of the wild-type P25X with the rpoN mutant strain G54. Analysis of two-dimensional polyacrylamide gel electrophoresis gels showed that 39 out of 355 prominent protein spots exhibited differential expression as a result of the insertional inactivation of rpoN. Identification of the protein spots by matrix-assisted laser desorption/ionization-time of flight/time of flight revealed a wide diversity of proteins that are affected by the sigma(54) mutation, the largest group being proteins that are involved in carbon metabolism. The strictly inducible gentisate 1,2-dioxygenase, one of two isofunctional copies of the key enzyme in the gentisate pathway, and enzymes of the TCA cycle, pyruvate metabolism and gluconeogenesis were part of this group. Other proteins that are part of the sigma(54) regulon include enzymes implicated in nitrogen metabolism, transport proteins, stress-response proteins and proteins involved in cell motility. The results of this study showed that sigma(54) plays a global regulatory role in the expression of a wide variety of genes in P. alcaligenes, including the wild-type response to the presence of the aromatic inducer, gentisate.

Electrophoresis, Gel, Two-Dimensional↗

PubMed2005

Structure and phase transition in self-assembled films of an anti-ferroelectric liquid crystal studied by two-dimensional correlation FTIR spectroscopy.

The FTIR spectra were measured for a self-assembled film of the anti-ferroelectric liquid crystal (AFLC) molecules over a temperature range of 40-150 degrees C. The frequency and intensity variations of the infrared spectra were discussed in terms of changes in molecular orientation, conformation and intra- and/or inter-molecular interaction during phase transitions. The two-dimensional (2d) correlation analysis revealed that two hydrocarbon chains have different orientation behaviors, the shorter hydrocarbon chain is parallel to molecular long axis and the longer one is perpendicular to it. The splitting of the C=O stretching band indicated that the s-cis and the s-trans conformers of the ester group coexist in the self-assembly film. During the phase transitions, in mesogen part the C=O group adjacent to the chiral part is first response with temperature changing, following the C=O group between two phenyl rings, and eventually the phenyl rings; and the respondence with temperature of methyl is slower than that of methylene in alkyl chains.

Phase Transition↗

PubMed2005

[Study of the expression profile of immunogenesis associated genes in tuberculosis by microarray].

OBJECTIVE: To explore the difference of gene expression profile in tuberculosis patients. METHODS: mRNA levels of pleural fluid and peripheral blood mononuclear cells (PBMC) in tuberculous pleurisy and lung cancer patients were compared by cDNA microarray. Paired mRNAs from fluid specimens of tuberculosis and lung cancer cases were labeled with different fluorochromes during cDNA probe synthesis in a reverse-transcription reaction. The signal intensity of each spot was measured by laser scanner and gene expression was quantified as the tubercle-to-normal fluorescence ratio (T:N ratio). The gene was defined as over expression when the T:N ratio was greater than 2.0 and under expression when the ratio was less than 0.5. RESULTS: Among 626 immunogenesis associated genes there were 53 differences, of which 31 (tnf-alpha, ig-lambda, il-17, il-17r, hla-dp, lcp1, tcralpha, tcrbeta, hsp75, cxcr4, fyb, hla-g, hla-a, il18bp, il-2r, lt-beta, il-8, ip-10, mcp-1, il-12, il-12r, il-10, canx, irf2, ifn-gamma, tlr, il-1, il-7, tlr, lsp-1, il-14)were higher and 22 (il-4, il-18, il-15, ifg-1, scya14, ablim, peci, ppid, hsf 2, actg2, maoa, ttid, gatm, tgfb3, insr, thbd, trap1, tcrgamma, tcrdelta, il-13r, il-11, igf1, a2m)were lower in tuberculous pleurisy than those in the control. CONCLUSIONS: The immunogenesis of tuberculosis involves multi-genetic expression changes, such as tnf-alpha, il-17, il-12, tcralpha, tcrbeta, hsp75, cxcr4, il-4, il-18, il-15 etc., the expression profile of which changed dramatically. The results provide new insight for understanding of the pathogenic mechanisms of tuberculosis and exploring new therapeutic strategies.

Adult↗

PubMed2005

[Polymerase chain reaction-single strand conformation polymorphism analysis combined with nucleic acid hybridization to detect ofloxacin-resistant Mycobacterium tuberculosis mutation selected in vitro].

OBJECTIVE: To explore the feasibility of utilizing polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis combined with Southern blot to detect ofloxacin (OFLX)-resistant Mycobacterium tuberculosis, and figure out the boundary between the OFLX-susceptible and resistant Mycobacterium tuberculosis. METHODS: OFLX-resistant Mycobacterium tuberculosis bacilli were induced in vitro and their minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) were determined. The 320 bp segments of gyrA gene were amplified by PCR and their polymorphism was tested by SSCP from H(37)Rv, H(37)Ra and those induced OFLX-resistant strains. To prove the repeatability of PCR-SSCP combined with Southern blot, 36 clinical isolated OFLX-resistant strains were tested. RESULTS: All of the 85 OFLX-resistant mutations involved in this study were identified to have gyrA mutations. The results showed that there was an overlap if OFLX 10 microg/ml was used as a criteria for discriminating susceptible and resistant strains. Compared with the H(37)Ra, the similar single-stranded shift caused by the single-stranded conformation change was viewed in the 36 clinical isolated OFLX-resistant strains by PCR-SSCP combined with Southern hybridization. CONCLUSIONS: PCR-SSCP analysis combined with Southern blot can clearly distinguish OFLX-susceptible from OFLX-resistant strains. The results suggest that as a cut-off point between OFLX-susceptible and low-level OFLX-resistant to Mycobacterium tuberculosis, OFLX concentration of 10 microg/ml is considered to be a better one.

Antitubercular Agents↗

PubMed2004

Formation and stability of rare earth metalloporphyrin monolayer films on amino-terminated silanized quartz surfaces studied by ultraviolet-visible and X-ray photoelectron spectroscopy.

We investigated the fabrication of self-assembled monolayers of 5,10,15,20-tetra-(p-chlorophenyl)-porphyrin metal hydroxyl compounds (MOH; M=Gd, Tb, Er, Lu) on amino-terminated silanized quartz surfaces using ultraviolet-visible (UV-vis) and X-ray photoelectron spectroscopy (XPS). The orientation of MOH molecules in the films, the kinetics of the adsorption of MOH from a chloroform solution on an amino-terminated quartz substrate, and the stability of the metalloporphyrin films under natural light, UV light, and acidic and basic conditions were studied by UV-vis spectroscopy. The results indicate that the central metal is crucial in the formation of self-assembled porphyrin films and that the stability of the MOH SAMs also depends on the central metal. Under natural and UV light irradiation conditions, the stability of the MOH SAMs depends on the strength of the M-N bonds between the central metal and pyrrole nitrogens or between the central metal and the axial ligand. In the acidic conditions, the UV-vis spectra of the MOH SAMs show decreases in the absorbance and blue shifts. These spectral changes lead us to suggest that the four M-N bonds between the central metal and the pyrrole nitrogens of the porphyrins are cleaved and the resulted porphyrins are protonated under acidic conditions. Thus, it is likely that the protonated porphyrins and MOH form pi-pi complexes with a parallel stacking of the macrocycles through the electrostatic attractive interaction in the SAMs, resulting in the blue shifts of the Soret bands of the SAMs.

Journal Article↗

PubMed2004

Self-assembled metal colloid films: two approaches for preparing new SERS active substrates.

In this paper, we propose two new approaches for preparing active substrates for surface-enhanced Raman scattering (SERS). In the first approach (method 1), one transfers AgI nanoparticles capped by negatively charged mercaptoacetic acid from a AgI colloid solution onto a quartz slide and then deoxidizes AgI to Ag nanoparticles on the substrate. The second approach (method 2) deoxidizes AgI to Ag nanoparticles in a colloid solution and then transfers the Ag nanoparticles capped by negatively charged mercaptoacetic acid onto a quartz slide. By transfer of the AgI/Ag nanoparticles from the colloid solutions to the solid substrates, the problem of instability of the colloid solutions can largely be overcome. The films thus prepared by both approaches retain the merits of metal colloid solutions while they discharge their shortcomings. Accordingly, the obtained Ag particle films are very suitable as SERS active substrates. SERS active substrates with different coverages can be formed in a layer-by-layer electrostatic assembly by exposing positively charged surfaces to the colloid solutions containing oppositely charged AgI/Ag nanoparticles. The SERS active substrates fabricated by the two novel methods have been characterized by means of atomic force microscopy (AFM) and ultraviolet-visible (UV-vis) spectroscopy. The results of AFM and UV-vis spectroscopy show that the Ag nanoparticles grow with the increase in the number of coverage and that most of them remain isolated even at high coverages. Consequently, the surface optical properties are dominated by the absorption due to the isolated Ag nanoparticles. The relationship between SERS intensity and surface morphology of the new active substrates has been investigated for Rhodamine 6G (R6G) adsorbed on them. It has been found that the SERS enhancement depends on the size and aggregation of the Ag particles on the substrates. Especially, we can obtain a stronger SERS signal from the substrate prepared by method 1, implying that for the metal nanoparticles capped with stabilizer molecules such as mercaptoacetic acid, the in situ deoxidization in the film is of great use in preparing SERS active substrates. Furthermore, we have found that the addition of Cl- into the AgI colloid solution changes the surface morphology of the SERS active substrates and favors stronger SERS enhancement.

Journal Article↗

PubMed2004

Proteome analysis of gentisate-induced response in Pseudomonas alcaligenes NCIB 9867.

Pseudomonas alcaligenes NCIB 9867 (P25X wild-type) is capable of degrading aromatic hydrocarbons via the gentisate pathway. Biochemical characterization of P25X mutants indicated that it has isofunctional enzymes for the mono- and dioxygenase-catalyzed reactions. One set of the enzymes is constitutive whereas the other is strictly inducible. To date, only the gene encoding the constitutively-expressed gentisate dioxygenase had been cloned and characterized. A mutant strain of P25X, designated G56, which had the constitutive copy of the gentisate 1,2-dioxygenase gene interrupted by a streptomycin/spectinomycin resistance gene cassette, was found to express gentisate dioxygenase, but only when the cells were induced by gentisate. The proteome profiles of P. alcaligenes P25X and mutant G56 cells grown in the presence and absence of gentisate were compared after two-dimensional polyacrylamide gel electrophoresis. Eight distinctive protein spots (designated M1-M8) which were observed only in induced cells of strain G56 but absent in noninduced cells were further analyzed by matrix-assisted laser desorption/ionization-time of flight, quadrupole-TOF and N-terminal sequencing. Of the 15 proteins (including seven up-regulated) examined, 13 showed sequence similarities to proteins with assigned functions in other microorganisms. The identification of protein M5 which showed high homology to a gentisate dioxygenase from Ralstonia sp. U2 indicated the putative function of this protein being consistent with the inducible gentisate 1,2-dioxygenase in P. alcaligenes. In addition, the induction of stress proteins and other adaptation phenomena were also observed.

Bacterial Proteins↗

PubMed2004

Promotion of the growth of Crocus sativus cells and the production of crocin by rare earth elements.

La3+ and Ce3+, either singly or a mixture, promoted crocin production of Crocus sativus callus but Nd3+ had little effect and all metal ions were toxic above 100 microM. La3+ (60 microM) promoted growth of callus significantly but increased crocin only slightly. Ce3+ (40 microM) significantly promoted crocin production but had little effect on cell growth. La3+ (60 microM) and Ce3+ (20 microM) together gave the highest dry weight biomass (20.4 g l(-1)), crocin content (4.4 mg g(-1)) and crocin production (90 mg l(-1)) which were, respectively, 1.7-fold, 4.2-fold and 7.1-fold of those without additions. Nd3+ (40 microM) only slightly promoted cell growth and crocin production.

Carotenoids↗

PubMed2004

Translational accuracy during exponential, postdiauxic, and stationary growth phases in Saccharomyces cerevisiae.

When the yeast Saccharomyces cerevisiae shifts from rapid growth on glucose to slow growth on ethanol, it undergoes profound changes in cellular metabolism, including the destruction of most of the translational machinery. We have examined the effect of this metabolic change, termed the diauxic shift, on the frequency of translational errors. Recoding sites are mRNA sequences that increase the frequency of translational errors, providing a convenient reporter of translational accuracy. We found that the diauxic shift causes no overall change in translational accuracy but does cause a strong reduction in the frequency of one type of programmed error: Ty +1 frameshifting. Genetic data suggest that this effect may be due to changes in the relative amounts of tRNA participating in translation elongation. We discuss possible implications for expression strategies that use recoding.

Codon↗

PubMed2004

Novel method for preparing controllable and stable silver particle films for surface-enhanced Raman scattering spectroscopy.

A new surface-enhanced Raman scattering (SERS) active substrate has been developed based on our previous study. Small silver nanoparticles on a quartz slide can be enlarged by using a mixture of commercially available reagents called Silver Enhancer and Initiator. The optical properties and characteristics of the new substrate have been investigated by ultraviolet-visible (UV-Vis) spectroscopy and atomic force microscopy (AFM). The results indicate that the small silver nanoparticles grow and some silver aggregates emerge on the quartz slide after the slide is immersed into the Silver Enhancer and Initiator Mixture (SEIM). The average diameter of the silver nanoparticles on the substrate becomes approximately double after the immersion into SEIM for 20 s. 1,4-bis[2-(4-pyridyl)ethenyl]-benzene (BPENB) was used as a Raman probe to evaluate the enhancement ability of the new silver substrate. It has been found that the SERS intensity can be increased about 10 times by using the substrate treated by SEIM compared with that without being treated by SEIM. Interestingly enough, the SERS enhancement increases with time. This may be due to the reorganization of silver nanoparticles on the quartz surface. The new substrate can remain active for more than 90 days. The adsorption mode of BPENB on the new substrate and the dependence of the BPENB configurations on the concentration of BPENB in methanol solution have also been investigated by SERS or UV-Vis spectroscopy. The SERS spectra of a self-assembled monolayer (SAM) BPENB film adsorbed on a silver substrate treated by SEIM show that BPENB molecules are chemically absorbed through the Ag-N bond. Consequently, a nearly perpendicular orientation of BPENB on the silver surface is proposed. The SERS spectra of BPENB SAMs on the new substrates fabricated from methanol solutions with different concentrations are compared. The concentration dependence of the SERS spectra reveals that the BPENB molecules are adsorbed on the silver film as monomers when the film is prepared from the solution with a lower concentration (<4 x 10(-6) M) and as aggregates when it is prepared from the solution with a higher concentration (>1 x 10(-5) M).

Journal Article↗