Aggregation of DNA-Grafted Nanoparticles in Water: The Critical Role of Sequence-Dependent Conformation of DNA Coating

Aggregation behavior of nanoparticles in water, particularly in the presence of surface coating, is a fundamental behavior to understand as it closely relates to the material function, reactivity, and toxicity. Engineered DNA, an important type of surface coating, is essentially different from conventional polymeric coatings with homogeneous repeating units. The heterogeneous nature of DNA with numerous combinations of the four nucleotides poses a challenge to understand the aggregation of nanoparticles coated with them. In this study, we use both experimental and computational approaches to study how DNA properties influence the aggregation of DNA-conjugated gold nanoparticles (DNA-AuNPs). Aggregation kinetics under different pH values and in three salts (NaCl, CaCl2, and MgCl2) were investigated. Overall, DNA-AuNPs demonstrated similar aggregation behavior of electrosterically stabilized nanoparticles, where the surface coating layer thickness played a determining role. The underlying interactions between DNA-AuNPs were analyzed by an extended DLVO model, and the excluded volume repulsion, which varied as a function of layer thickness, was the dominant stabilizing repulsion. Interestingly, the DNA sequence was found to cause different layer thicknesses and thus profoundly different aggregation behaviors in the presence of cations. The interactions between DNA strands with different sequences and surrounding counterions were investigated via molecular dynamics simulations. The simulation results were consistent with experimental observations and supported the sequence-dependent conformational change of DNA coating. Our study provides new molecular-level insights into aggregation of nanoparticles with heterogeneous surface coating such as DNA

Effect of parameter z on the governance volume.

The development of digital technology and the sharing economy has extended corporations’ innovative activities beyond the corporation’s boundaries, so it has become more urgent to govern the lack of social responsibility and alienation of platform corporations from the perspective of social agents. First, the platform’s CSR classification and social responsibility governance’s main content are analyzed in this research. Then, this study uses government agencies, platform corporations, users, and the public as governance subjects and compares governance decisions with and without public and user oversight. Finally, the optimal balance strategy for each governing subject, the optimal trajectory of governance volume, and the trajectory of total revenue are obtained. The study found that: 1) Public and user supervision can improve the governance volume while encourage the governance motivation of government agencies and platform corporations. 2) The level of user supervision effort has a greater impact on the total governance revenue than public supervision. 3) The revenue of the system and the governance volume are greater in a centralized decision-making process, indicating that those involved should co-operate in governance based on the principle of mutual benefit. 4) The platform corporation has an incompatible but unified relationship between its social duty and financial success.</div

In decentralized governance that considers public and user supervision, the effect of changes in parameters <i>s</i> and <i>u</i> on the total governance revenue.

In decentralized governance that considers public and user supervision, the effect of changes in parameters s and u on the total governance revenue.</p

In centralized governance that considers public and user supervision, the effect of changes in parameters s and u on the total governance revenue.

In centralized governance that considers public and user supervision, the effect of changes in parameters s and u on the total governance revenue.</p

The effect of changes in parameters c and ωon the total governance volume under centralized decision-making without consideration of users and public scrutiny.

The effect of changes in parameters c and ωon the total governance volume under centralized decision-making without consideration of users and public scrutiny.</p

The effect of changes in parameters <i>c</i> and<i>ω</i>on the total governance volume under centralized decision-making with consideration of users and public scrutiny.

The effect of changes in parameters c andωon the total governance volume under centralized decision-making with consideration of users and public scrutiny.</p

Comparison of the governance volume.

The development of digital technology and the sharing economy has extended corporations’ innovative activities beyond the corporation’s boundaries, so it has become more urgent to govern the lack of social responsibility and alienation of platform corporations from the perspective of social agents. First, the platform’s CSR classification and social responsibility governance’s main content are analyzed in this research. Then, this study uses government agencies, platform corporations, users, and the public as governance subjects and compares governance decisions with and without public and user oversight. Finally, the optimal balance strategy for each governing subject, the optimal trajectory of governance volume, and the trajectory of total revenue are obtained. The study found that: 1) Public and user supervision can improve the governance volume while encourage the governance motivation of government agencies and platform corporations. 2) The level of user supervision effort has a greater impact on the total governance revenue than public supervision. 3) The revenue of the system and the governance volume are greater in a centralized decision-making process, indicating that those involved should co-operate in governance based on the principle of mutual benefit. 4) The platform corporation has an incompatible but unified relationship between its social duty and financial success.</div

Effect of parameter <i>z</i> on the total revenue.

The development of digital technology and the sharing economy has extended corporations’ innovative activities beyond the corporation’s boundaries, so it has become more urgent to govern the lack of social responsibility and alienation of platform corporations from the perspective of social agents. First, the platform’s CSR classification and social responsibility governance’s main content are analyzed in this research. Then, this study uses government agencies, platform corporations, users, and the public as governance subjects and compares governance decisions with and without public and user oversight. Finally, the optimal balance strategy for each governing subject, the optimal trajectory of governance volume, and the trajectory of total revenue are obtained. The study found that: 1) Public and user supervision can improve the governance volume while encourage the governance motivation of government agencies and platform corporations. 2) The level of user supervision effort has a greater impact on the total governance revenue than public supervision. 3) The revenue of the system and the governance volume are greater in a centralized decision-making process, indicating that those involved should co-operate in governance based on the principle of mutual benefit. 4) The platform corporation has an incompatible but unified relationship between its social duty and financial success.</div

The effect of changes in parameters <i>c</i> and<i>ω</i>on the total governance volume under centralized decision-making without consideration of users and public scrutiny.

The effect of changes in parameters c andωon the total governance volume under centralized decision-making without consideration of users and public scrutiny.</p

Research framework.

The development of digital technology and the sharing economy has extended corporations’ innovative activities beyond the corporation’s boundaries, so it has become more urgent to govern the lack of social responsibility and alienation of platform corporations from the perspective of social agents. First, the platform’s CSR classification and social responsibility governance’s main content are analyzed in this research. Then, this study uses government agencies, platform corporations, users, and the public as governance subjects and compares governance decisions with and without public and user oversight. Finally, the optimal balance strategy for each governing subject, the optimal trajectory of governance volume, and the trajectory of total revenue are obtained. The study found that: 1) Public and user supervision can improve the governance volume while encourage the governance motivation of government agencies and platform corporations. 2) The level of user supervision effort has a greater impact on the total governance revenue than public supervision. 3) The revenue of the system and the governance volume are greater in a centralized decision-making process, indicating that those involved should co-operate in governance based on the principle of mutual benefit. 4) The platform corporation has an incompatible but unified relationship between its social duty and financial success.</div