Search

In this paper, firstly, the resonance light scattering spectra of aflatoxin B 1 (AFB 1 ) and DNA were measured by resonance light scattering spectroscopy (RLS), and the DNA binding saturation value (DBSV) of AFB 1 was calculated from their spectral results. Then the interaction intensity between DNA and AFB 1 and the effects of some external factors on the interaction between DNA and AFB 1 were evaluated by corresponding DBSVs, so as to establish and optimize a way for removing AFB 1 by DNA. DBSV of AFB 1 was 2.04 at 30℃ and pH 7.40. However, after adding sodium ion, calcium ion, vitamin E, vitamin C and D-glucose, DBSV of AFB 1 was changed to 2.72, 3.17, 2.67, 1.68 and 1.33 respectively. Correspondingly, the removal efficiency of AFB 1 by DNA was changed from 90.05% to 93.25%, 95.48%, 93.08%, 82.36% and 78.90% respectively. These results indicated that the external factors had a significant impact on the interaction between DNA and AFB 1 . Among them, some factors enhanced the interaction between DNA and AFB 1 , while some factors weakened the interaction between DNA and AFB1. The change of these external factors led to the corresponding changes in DBSV and the removal efficiency of AFB 1 . DBSV of AFB 1 could really be used as an index to evaluate the intensity of the interaction between DNA and AFB 1 , and to optimize the removal efficiency of AFB 1 by DNA. The experimental data also showed that the adsorption of AFB 1 to DNA was consistent with the pseudo-second-order kinetic model and the Freundlich isothermal model, was an exothermic and spontaneous process. All these results will give good references for establishing and optimizing a way of AFB 1 removal via DNA intercalation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Polycyclic aromatic hydrocarbons are environmental pollutants with strong carcinogenicity, indirect teratogenicity, and mutagenicity. This study explored the interaction mechanism of benzo(a)pyrene with free DNA in vitro by using various analytical methods. UV-vis spectra showed that benzo(a)pyrene and DNA formed a new benzo(a)pyrene-DNA complex. The thermal melting temperature of DNA increased by 12.7 °C, showing that the intercalation of benzo(a)pyrene into DNA could promote the stability of the DNA double helix structure. The intercalation of benzo(a)pyrene with DNA in vitro was further confirmed by fluorescence microscopy with magnetic beads. Fluorescence spectra showed that the interaction between DNA and benzo(a)pyrene decreased the fluorescence intensity of benzo(a)pyrene, and the maximum quenching rate was 27.89%. The quenching mode of benzo(a)pyrene was static quenching. Thermodynamic data showed that the main driving forces were van der Waals forces and hydrogen bonds, and the reaction was spontaneous. The results of this study provided a novel insight for the establishment of polycyclic aromatic hydrocarbon capture and elimination through polycyclic aromatic hydrocarbon-DNA intercalation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, DNA-functionalize-magnetic beads were investigated as sorbent materials for effective removing 1,2-benzanthracene (BaA) from water. In order to reveal the removal mechanism, the interaction mode between BaA and DNA was evaluated by using various characterization tools such as UV-visible and circular dichroism spectroscopy, fluorescence and resonance scattering spectroscopy, and agarose gel electrophoresis. In the presence of BaA, the melting temperature of DNA increased from 76.2 °C to 82.3 °C, which closely related to the intercalating of BaA. It was found that a part of the ethidium bromide (EB) binding sites to DNA were occupied by BaA in EB competing study. The results indicated that a new complex appeared between hsDNA and BaA, and the number of the binding sites (n) and the binding constants (K A ) at different temperatures were obtained. DNA binding saturation value (≈0.80) was obtained by resonance scattering spectra study. BaA could be enriched and removed by DNA-functionalize-magnetic beads via the intercalation, and the removal efficiency was 97.73% when the initial concentration was 2.45 x10 -6  mol·L -1 (559.31 μg/L).

The present study sought to evaluate the interaction between aflatoxin G 1 and free DNA in vitro through different analytical techniques. The UV-visible spectra results showed that the structure of DNA might be changed with a new aflatoxin G 1 -DNA complex forming, which indicated that the interacting mode between them was the intercalating mode. The DNA melting temperature increased by 12.80 °C, suggesting that the DNA double helix structure was more compact and stable through intercalation. The circular dichroism (CD) spectra results indicated that the interaction of aflatoxin G 1 with DNA induced the DNA base stacking changes. The results of agarose gel electrophoresis and fluorescence microscope further verified that the interacting mode between aflatoxin G 1 and DNA was intercalation mode. According to the fluorescence spectrum data, the binding constant was calculated 6.24 × 10 4 L·mol -1 . The thermodynamic results demonstrated that the reaction of aflatoxin G 1 intercalating to DNA was a spontaneous reaction. The elimination results suggested that aflatoxin G 1 could be enriched and removed by DNA intercalation through magnetic beads separation, with the removal efficiency of 93.73%. The study results would provide a theoretical basis for establishing a new aflatoxin removal method based on DNA intercalation.

In this paper, the binding characteristics of aflatoxin B 1 (AFB 1 ) with the herring sperm deoxyribonucleic acid (DNA) in vitro were investigated through different analytical methods. The ultraviolet-visible spectroscopy (UV-vis), fluorescence, and circular dichroism (CD) spectra results showed that a new AFB 1 -DNA complex was formed. All the results suggested that AFB 1 interacted with free DNA in vitro in an intercalating binding mode. The results of the DNA melting experiments also showed that the melting temperature of DNA increased by about 12.1 °C due to the addition of AFB 1 , which was supposed to be closely related to the intercalation of AFB 1 into DNA. The agar gel electrophoresis experiments further confirmed that the binding mode of AFB 1 and free DNA in vitro was indeed intercalation. In addition, the fluorescence quenching induced by adding AFB 1 to the ethidium bromide-DNA (EB-DNA) mixture indicated the presence of competitive non-covalent intercalating binding interaction with a competitive binding constant of 5.58 L/mol between AFB 1 , EB, and DNA. The thermodynamic data demonstrated that the main driving forces of the binding reaction were van der Waals forces and hydrogen bond. The resonance light scattering (RLS) assay results showed that the DNA binding saturation values of AFB 1 , EB, psoralen (PSO), and angelicin (ANG) were 2.14, 15.59, 0.74, and 0.74, respectively. These results indicated that the DNA binding capacity of AFB 1 was weaker than that of EB, but stronger than those of PSO and ANG., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The interaction of DNA with anthragallol (Ant) was investigated using ethidium bromide (EB) as a fluorescence probe, and the binding mechanism of Ant with DNA was researched via viscosity measurements. The results indicate that there is a complex of Ant and DNA, as confirmed by Ultraviolet visible absorption spectroscopy (UV-vis), Fluorescent and Resonance Light Scattering spectrum (RLS) and viscosity measurements. Ant molecules could intercalate with the base pairs of DNA as evidenced by the hyperchromic effect of absorption spectra, the relative viscosity of DNA and significant increases in the melting temperature. The binding constants of Ant and DNA were obtained by the fluorescence quenching technique. Furthermore, the binding mechanisms of the reaction of Ant with DNA were also investigated. The RLS assay successfully evaluated the saturated value and measured the potential toxicity of Ant. Adriamycin, chrysophanol, rhein, and alizarin can be used as references to build a method based on the mechanism of interactions with DNA and the DNA-saturation binding value to rapidly evaluate the potential toxicity of Ant., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this study, the interacting characteristics of dibenzo[a,h]anthracene (DBA) with free DNA in vitro were investigated through multiple conventional spectroscopic techniques. UV–vis absorption spectroscopy was used to initially explore whether there was an interaction between DBA and DNA. Fluorescence spectroscopy was exploited to explore the binding characteristics and binding force between DBA and DNA. Circular dichroism (CD) spectra and DNA thermal denaturation measurement are utilized to further explore the binding mode between DBA and DNA. Magnetic bead separation technique coupled with fluorescence microscopic observation visually demonstrated the binding between DBA and DNA, and the residual amount of DBA was measured by fluorescence intensity. The results show that DBA can bind to DNA in vitro through intercalation mode. In the process of forming DBA–DNA complex, hydrogen bond and van der Waals force play a major role. The binding constant (KA) and binding sites (n) are 2.039 × 105 L/mol and 1.0451 at 25 °C, respectively. Moreover, DNA can be used to capture DBA in the solution based on DBA–DNA intercalation, and its removal efficiency is 98.24%. This work can provide new insights for the establishment of a novel polycyclic aromatic hydrocarbons (PAHs) elimination method based on PAHs–DNA intercalation. [ABSTRACT FROM AUTHOR]

In the present paper, an optimized method to extract common carp sperm DNA (csDNA) from common carp testis, the mechanism of ethidium bromide (EtBr) interaction with csDNA, as well as the removal of EtBr pollutant by csDNA was studied. The results showed that high salt extraction method was suitable for extracting csDNA. Under the optimum conditions, the yield of csDNA extraction was as high as 11.7%. In addition, the results of UV–vis spectra, fluorescence spectra, and observation with fluorescence microscope indicated that csDNA could be intercalated by EtBr to form a stable complex, which confirmed that csDNA could be applied in removing EtBr pollutant. Based on the csDNA intercalation, EtBr pollutant was removed by csDNA effectively, which was 94.13%. This work not only provides a smart method to extract high purity and quality csDNA from byproducts of common carp testis but also provides an easily available csDNA to remove EtBr from pollutants. [ABSTRACT FROM AUTHOR]

The present study sought to evaluate the interaction between aflatoxin G1 and free DNA in vitro through different analytical techniques. The UV–visible spectra results showed that the structure of DNA might be changed with a new aflatoxin G1-DNA complex forming, which indicated that the interacting mode between them was the intercalating mode. The DNA melting temperature increased by 12.80 °C, suggesting that the DNA double helix structure was more compact and stable through intercalation. The circular dichroism (CD) spectra results indicated that the interaction of aflatoxin G1 with DNA induced the DNA base stacking changes. The results of agarose gel electrophoresis and fluorescence microscope further verified that the interacting mode between aflatoxin G1 and DNA was intercalation mode. According to the fluorescence spectrum data, the binding constant was calculated 6.24 × 104 L·mol−1. The thermodynamic results demonstrated that the reaction of aflatoxin G1 intercalating to DNA was a spontaneous reaction. The elimination results suggested that aflatoxin G1 could be enriched and removed by DNA intercalation through magnetic beads separation, with the removal efficiency of 93.73%. The study results would provide a theoretical basis for establishing a new aflatoxin removal method based on DNA intercalation. [ABSTRACT FROM AUTHOR]

The present study sought to evaluate the interaction between aflatoxin G1 and free DNA in vitro through different analytical techniques. The UV–visible spectra results showed that the structure of DNA might be changed with a new aflatoxin G1-DNA complex forming, which indicated that the interacting mode between them was the intercalating mode. The DNA melting temperature increased by 12.80 °C, suggesting that the DNA double helix structure was more compact and stable through intercalation. The circular dichroism (CD) spectra results indicated that the interaction of aflatoxin G1 with DNA induced the DNA base stacking changes. The results of agarose gel electrophoresis and fluorescence microscope further verified that the interacting mode between aflatoxin G1 and DNA was intercalation mode. According to the fluorescence spectrum data, the binding constant was calculated 6.24 × 104 L·mol−1. The thermodynamic results demonstrated that the reaction of aflatoxin G1 intercalating to DNA was a spontaneous reaction. The elimination results suggested that aflatoxin G1 could be enriched and removed by DNA intercalation through magnetic beads separation, with the removal efficiency of 93.73%. The study results would provide a theoretical basis for establishing a new aflatoxin removal method based on DNA intercalation. [ABSTRACT FROM AUTHOR]

[Display omitted] • After intercalating into DNA, the fluorescence of AFM 1 was significantly enhanced. • The binding ability of ssDNA to AFM 1 is weaker than that of dsDNA. • Both AFM 1 and EB can intercalate into DNA, they are competitive. • The binding mode between AFM 1 and DNA was confirmed to be intercalation. • AFM 1 can be removed from solution via the intercalation between DNA and AFM 1. To reveal the interaction between aflatoxin M 1 (AFM 1) and DNA, and then explore a new method to remove AFM 1 , spectroscopy, electrophoresis, and fluorescence microscopy were used. Fluorescence spectra assay showed that AFM 1 and ethidium bromide (EB) competed for the intercalation sites in DNA, and the binding constant between AFM 1 and DNA was 3.81 ± 0.1 × 107 L mol−1. The comparison of single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) in the fluorescence enhancement of AFM 1 further proved that the binding sites were between the base pairs of DNA. In the presence of AFM 1 , the melting temperature of DNA increased by 6.2 ° C, and the circular dichroism of DNA changed. These events were closely related to the intercalation between AFM 1 and DNA. The binding between AFM 1 and DNA was firm. AFM 1 and DNA did not separate in agarose gel electrophoresis. Based on the intercalation between AFM 1 and DNA, with DNA as an intermediate medium, AFM 1 can be indirectly adsorbed onto magnetic beads. Then, AFM 1 could be removed by magnetic separation. At an initial concentration of 10 μg/L, the removal efficiencies were 95.5%±3.7 and 85.5%±3.3 for aqueous solution and milk, respectively. This research result provided a direction in the detoxification of AFM 1 , which deserves to be developed further. [ABSTRACT FROM AUTHOR]

• Binding of benzo[b]fluoranthene to DNA was studied by multi-spectroscopic means, electrophoresis and fluorescence microscope. • Benzo[b]fluoranthene interacted with DNA by intercalation mode. • Van der Waals force and π-π packing were the stabilizing forces. • DNA as an adsorption material for removing PAHs based on intercalation binding was used. Benzo[b]fluorathene (BbF) is one of common polycyclic aromatic hydrocarbons with strong carcinogenic and teratogenic properties and mutagenicity in the environment. In this work, the mechanism underlying the relationship between BbF and herring sperm DNA (hs–DNA) in vitro under simulated physiological conditions was studied through multi-spectroscopic approaches (fluorescence spectroscopy, UV–Vis spectroscopy, resonance scattering spectra, and circular dichroism) coupled with agarose gel electrophoresis, fluorescence microscopy, and viscosity measurements. UV–vis and fluorescence spectra results showed that the BbF–DNA complexes formed with a binding constant of 8.95 ± 0.19 × 105 L/mol, and BbF bound to DNA by intercalative binding. These findings were further confirmed through circular dichroism, potassium iodide quenching experiment, salt ion effect tests, and viscosity measurement. Obtained from the resonance scattering spectral data, the saturation value of DNA with BbF was 2.4, revealing that BbF may cause DNA damage. The thermodynamic parameters revealed that the binding process was entropically driven by the spontaneous reaction between BbF and DNA. The main stabilizing forces between BbF and DNA were van der Waals force and π-π packing. Agarose gel electrophoresis and fluorescence microscopy results intuitively verified that the interaction mode of BbF and DNA was intercalation. Moreover, on the basis of intercalative binding between BbF and DNA, DNA and magnetic beads were used to selectively capture BbF, and the removal rate of BbF was 98.76%. This study provides mechanisms underlying the toxicity of BbF and novel insights into BbF clearance methods based on BbF–DNA intercalation. [ABSTRACT FROM AUTHOR]