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At least 37 records · Page 2

Likelihood-based signal and noise analysis for docking of models into cryo-EM maps

Fast, reliable docking of models into cryo-EM maps requires understanding of the errors in the maps and the models. Likelihood-based approaches to errors have proven to be powerful and adaptable in experimental structural biology, finding applications in both crystallography and cryo-EM. Indeed, previous crystallographic work on the errors in structural models is directly applicable to likelihood targets in cryo-EM. Likelihood targets in Fourier space are derived here to characterize, based on the comparison of half-maps, the direction- and resolution-dependent variation in the strength of both signal and noise in the data. Because the signal depends on local features, the signal and noise are analysed in local regions of the cryo-EM reconstruction. The likelihood analysis extends to prediction of the signal that will be achieved in any docking calculation for a model of specified quality and completeness. A related calculation generalizes a previous measure of the information gained by making the cryo-EM reconstruction.

59 BASIC BIOLOGICAL SCIENCES↗

Likelihood-based docking of models into cryo-EM maps

Optimized docking of models into cryo-EM maps requires exploiting an understanding of the signal expected in the data to minimize the calculation time while maintaining sufficient signal. The likelihood-based rotation function used in crystallography can be employed to establish plausible orientations in a docking search. A phased likelihood translation function yields scores for the placement and rigid-body refinement of oriented models. Optimized strategies for choices of the resolution of data from the cryo-EM maps to use in the calculations and the size of search volumes are based on expected log-likelihood-gain scores computed in advance of the search calculation. Tests demonstrate that the new procedure is fast, robust and effective at placing models into even challenging cryo-EM maps.

59 BASIC BIOLOGICAL SCIENCES↗

Likelihood-based interactive local docking into cryo-EM maps in ChimeraX

The interpretation of cryo-EM maps often includes the docking of known or predicted structures of the components, which is particularly useful when the map resolution is worse than 4 Å. Although it can be effective to search the entire map to find the best placement of a component, the process can be slow when the maps are large. However, frequently there is a well-founded hypothesis about where particular components are located. In such cases, a local search using a map subvolume will be much faster because the search volume is smaller, and more sensitive because optimizing the search volume for the rotation-search step enhances the signal to noise. A Fourier-space likelihood-based local search approach, based on the previously published em_placement software, has been implemented in the new emplace_local program. Tests confirm that the local search approach enhances the speed and sensitivity of the computations. An interactive graphical interface in the ChimeraX molecular-graphics program provides a convenient way to set up and evaluate docking calculations, particularly in defining the part of the map into which the components should be placed.

59 BASIC BIOLOGICAL SCIENCES↗

Fragment binding to the Nsp3 macrodomain of SARS-CoV-2 identified through crystallographic screening and computational docking

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) macrodomain within the nonstructural protein 3 counteracts host-mediated antiviral adenosine diphosphate–ribosylation signaling. This enzyme is a promising antiviral target because catalytic mutations render viruses nonpathogenic. Here, we report a massive crystallographic screening and computational docking effort, identifying new chemical matter primarily targeting the active site of the macrodomain. Crystallographic screening of 2533 diverse fragments resulted in 214 unique macrodomain-binders. An additional 60 molecules were selected from docking more than 20 million fragments, of which 20 were crystallographically confirmed. X-ray data collection to ultra-high resolution and at physiological temperature enabled assessment of the conformational heterogeneity around the active site. Several fragment hits were confirmed by solution binding using three biophysical techniques (differential scanning fluorimetry, homogeneous time-resolved fluorescence, and isothermal titration calorimetry). The 234 fragment structures explore a wide range of chemotypes and provide starting points for development of potent SARS-CoV-2 macrodomain inhibitors.

59 BASIC BIOLOGICAL SCIENCES↗

Synthesis, in vitro antifungal evaluation and docking studies of novel derivatives of imidazoles and benzimidazoles

A series of imidazole and benzimidazole derivatives was designed and prepared in good yields via convenient and efficient two steps synthetic route using readily available starting materials. The structures of the synthesized compounds and their intermediates were characterized by IR, {sup 1}H-NMR, {sup 13}C-NMR spectroscopy, and MS spectra. The in vitro antifungal activities of the targeted compounds were evaluated against Candida Albicans, Cryptococcus neoformans, Aspergillus niger, and Microsporum gypseum. The results showed that some of these azole-derivatives exhibited good to excellent antifungal activities against the used strains especially C. neoformans and A. niger. For example, compound 6b, 1-[2-Phenyl-2-(3-phenyl-propoxy)-ethyl]-1H-imidazole, was quite effective on the C. neoformans, A. niger, and M. gypseum with MIC 1.95 µg mL{sup −1}. The in silico molecular docking study was also done on the synthesized compounds and the results showed they have minimum binding energy and relatively good affinity toward cytochrome P450. According to the in vitro antifungal results and molecular docking studies, the compounds 6a–d can be selected as lead compounds for further pharmaceutical investigations.

60 APPLIED LIFE SCIENCES↗

Fluorophenols bearing nitrogenated heterocycle moieties, a class of novel Keap1-Nrf2 protein-protein interaction inhibitors: synthesis, antioxidant stress screening and molecular docking

In the present study, we introduced the nitrogenated heterocycles and fluorine atoms into the 2,5′-dibromo-4,5,2′-trihydroxyl diphenylmethanone (LM49), a bromophenol analog previously reported for its strong antioxidant ability involving in the Keap1–Nrf2 pathway. Twenty-seven fluorophenols 6a–6g, 8a–8k, 10a–10g, and 12a–12b were prepared, evaluated for their antioxidant activity in EA.hy926 cells, and investigated their interacted approach and probable mode of action with key protein Keap1 by molecular docking. Fluorophenols 6f, 8d, 8f, 8h, and 8i with EC{sub 50} values ranging from 0.82 to 6.71 µM were found to be more active compared with the standard control quercetin (EC{sub 50} = 18 µM). Among them, compound 8h with an EC{sub 50} value of 0.82 µM showed the identical activity to lead compound LM49 (EC{sub 50} = 0.7 µM). Moreover, the preferable water solubility and forming salt possibility of 8h contribute to its druggability. Further molecular docking of the optimal compound 8h with key protein Keap1 indicated that 8h stably bonded to the receptor protein by the formation of hydrogen bonds, the conjugated six-membered ring was close to the key residue Arg-415 attached to the Nrf2 on Keap1-Kelch, affecting its properties, and the change leaded to the dissociation of Nrf2 from the junction with Keap1-Kelch into the nucleus exerting its antioxidant protective effect. This study introduced a class of fluorophenols containing nitrogenated heterocycles for the development of novel Keap1-Nrf2 protein–protein interaction (PPI) inhibitors. Keap1-Kelch is suggested the most potential target protein for such class of halophenols.

60 APPLIED LIFE SCIENCES↗

Design, synthesis, molecular docking, antimicrobial, and antioxidant activities of new phenylsulfamoyl carboxylic acids of pharmacological interest

Abstracts: The research explores the facile synthesis of some new phenylsulfamoyl carboxylic acids, their molecular docking, antimicrobial, and antioxidant activities. The procedure involved the mild reaction of amino acids with benzenesulfonyl chloride in a medium of aqueous base. The compounds were characterized using FTIR, {sup 1}H-NMR, {sup 13}C-NMR, and an elemental analysis. They were tested for their antimicrobial activities against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Candida albicans, and Aspergillus niger microorganisms. The antioxidant activity of the compounds were measured in vitro by the inhibition of generated stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The molecular docking was carried out properly and five different disease conditions were studied, namely: trypanosomiasis, malaria, bacterial, fungal infections, and oxidative stress. From the results, compounds 4c, 4d, 4e, and 4g possess more excellent in vitro antibacterial and antifungal activities than the standard drug Ofloxacin used. Compound 4e displayed the most excellent antioxidant activity. Compound 4g showed significant 2D interaction with amino acid residue of urate oxidase from Aspergillus flavus complexed with uracil. Interestingly, compounds 4a, 4c, 4d, 4e, and 4g exhibited excellent antibacterial, antifungal, antioxidant, antitrypanosome, and antimalaria activities comparable to the corresponding standard drugs such as Penicillin, Ketoconazole; α-Tocopherol, Melarsoprol, and Chloroquine respectively. All the compounds were confirmed drug-like according to “Lipinski’s rule of five”. The compounds were found to be promising antibacterial, antifungal, antioxidant, and antitrypanosome agents.

60 APPLIED LIFE SCIENCES↗

Host cell and viral protease targets of human SERPINs identified by in silico docking

Serine protease inhibitors (SERPINs) are involved in various physiological processes and diseases, such as inflammation, cancer metastasis, and neurodegeneration. Their role in viral infections is poorly understood, as their expression patterns during infection and the range of proteases they target have yet to be fully characterized. Here, we show widespread expression of human SERPINs in response to respiratory virus infections, both in bronchioalveolar lavages from COVID-19 patients and in polarized human airway epithelial cultures. Using in silico docking of 10 SERPINs to 48 host proteases, we confirm known targets and predict new interactions. Protease activity assays validated selected interactions, confirming the newly predicted host targets for PAI-1 (SERPINE1) and PAI-2 (SERPINB2). PAI-1 inhibits cathepsin L, essential for SARS-CoV-2 maturation, and suppresses multi-cycle replication of both ancestral SARS-CoV-2 WA-1 and its variant Omicron BA.1. In addition, we identify PAI-2 as an antiviral SERPIN that reduces infectivity of human adenovirus 5 by directly inhibiting the adenoviral protease. Our study leverages in silico docking using full-length 3D protein structures to uncover new SERPIN targets, offering a range of candidate targets for therapeutic interventions.

59 BASIC BIOLOGICAL SCIENCES↗

Molecular docking predictions of fragrance binding to human leukocyte antigen molecules

Abstract Background Over 4000 small chemicals have been identified as allergens capable of inducing skin sensitization. Many sensitizers are hypothesized to act as haptens producing novel antigens, which can be presented to T cells by human leukocyte antigens (HLAs). Recent studies suggest that some chemical allergens use hapten‐independent mechanisms. Objective To determine whether molecular docking can identify HLA molecules that bind skin‐sensitizing chemical allergens. Methods Structural models of HLA molecules were used as the basis for molecular docking of 22 chemical allergens. Allergens predicted to bind HLA‐B*57:01 were tested for their ability to stimulate T cells by the use of proliferation and interferon‐gamma enzyme‐linked immunospot assays. Results Chemical allergens that did not satisfy the criteria for hapten activity in vitro were predicted to bind more strongly to common HLA isoforms than those with known hapten activity. HLA‐B*57:01, which is an HLA allele required for drug hypersensitivity reactions, was predicted to bind several allergens, including benzyl benzoate, benzyl cinnamate, and benzyl salicylate. In in vitro T cell stimulation assays, benzyl salicylate and benzyl cinnamate were found to stimulate T cell responses from HLA‐B*57:01 carriers. Conclusions These data suggest that small‐molecule skin sensitizers have the potential to interact with HLA, and show that T cell‐based in vitro assays may be used to evaluate the immunogenicity of skin‐sensitizing chemicals.

Schutte, Ryan J.↗

Integrated structural model of the palladin–actin complex using XL ‐ MS , docking, NMR , and SAXS

Abstract Palladin is an actin‐binding protein that accelerates actin polymerization and is linked to the metastasis of several types of cancer. Previously, three lysine residues in an immunoglobulin‐like domain of palladin have been identified as essential for actin binding. However, it is still unknown where palladin binds to F‐actin. Evidence that palladin binds to the sides of actin filaments to facilitate branching is supported by our previous study showing that palladin was able to compensate for Arp2/3 in the formation of Listeria actin comet tails. Here, we used chemical crosslinking to covalently link palladin and F‐actin residues based on spatial proximity. Samples were then enzymatically digested, separated by liquid chromatography, and analyzed by tandem mass spectrometry. Peptides containing the crosslinks and specific residues involved were then identified for input to the HADDOCK docking server to model the most likely binding conformation. Small‐angle x‐ray scattering was used to provide further insight into palladin flexibility and the binding interface, and NMR spectra identified potential interactions between palladin's Ig domains. Our final structural model of the F‐actin:palladin complex revealed how palladin interacts with and stabilizes F‐actin at the interface between two actin monomers. Three actin residues that were identified in this study also appear commonly in the actin‐binding interface with other proteins such as myotilin, myosin, and tropomodulin. An accurate structural representation of the complex between palladin and actin extends our understanding of palladin's role in promoting cancer metastasis through the regulation of actin dynamics.

Sargent, Rachel [Department of Chemistry and Bioch↗

Synthesis, molecular docking, and apoptogenic efficacy of novel N-heterocycle analogs to target B-cell lymphoma 2/X-linked inhibitors of apoptosis proteins to regress melanoma

The novel series of piperidine conjugated benzophenone analogs with amide link 11a–l were synthesized in a multistep process. The structures of these compounds were confirmed by IR, {sup 1}H, {sup 13}C, NMR, and mass spectra and also by elemental analyses. The newly synthesized molecules were screened for selectivity against cancers of different origin through cell based assay system using B16F10, A375, A549, HepG2, ACHN, and MCF7 cells. The results postulated that compound 11f with two bromo groups at the para position in rings A and E and two methyl groups at ortho position in rings B and D evokes target specific action against melanoma highlighting the importance of substituted groups. Down the line studies further inferred compound 11f evokes the apoptotic cellular event leading to cell death. Investigation of eventual mechanism revealed that compound 11f turned out to be a dual inhibitor of B-cell lymphoma-2 and X-linked inhibitors of apoptosis causing the up regulation of Bax and Bad. Further, the antiproliferative effects were mimicked in murine melanoma with similar mechanisms. Molecular docking experiments further confirmed that compound 11f possessed a superior affinity for of B-cell lymphoma-2 and X-linked inhibitors of apoptosis through strong hydrogen bonds. The study implies the identification of compound 11f with selective target against melanoma by inducing apoptogenic effect, which could be the future hope for the treatment of skin cancer.

60 APPLIED LIFE SCIENCES↗

Synthesis, in vitro assays, molecular docking, theoretical ADMET prediction, and evaluation of 4-methoxy-phenylthiazole-2-amine derivatives as acetylcholinesterase inhibitors

Based on the cholinergic hypothesis of the reported compound, N-(4-(4-methoxy-phenyl)thiazol-2-yl)-3-(pyrrolidin-1-yl)propionamide, which had a good inhibitory activity to acetylcholinesterase (AChE), the new 4-methoxy-phenylthiazole-2-amine derivatives as AChE inhibitors (AChEIs) have been designed and synthesized in this study. Their chemical structures were confirmed by proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, mass spectrometry, and infrared. Furthermore, their inhibitory activities against AChE in vitro were also tested by Ellman spectrophotometry, and the inhibitory activity test results showed that most of the compounds of 4-methoxy-phenylthiazole-2-amine derivatives had a certain AChE inhibitory activity in vitro, and the IC{sub 50} (half-maximal inhibitory concentration) value of compound 5g was 5.84 μmol/L, which was higher than that of the reference compound, rivastigmine. Moreover, it had almost no inhibitory effect on butyrylcholinesterase. In addition, compound 5g was subjected to enzyme inhibition kinetics experiments, and the result of Lineweaver–Burk’s V{sup −1}–[S]{sup −1} double-reciprocal plot showed that the acting type of compound 5g was mixed inhibition type. Furthermore, the AChE inhibitory activity mechanism of compound 5g was explored by the conformational analysis and molecular docking, which was based on the principle of the four-point pharmacophore model necessary for AChE inhibition. Finally, in silico molecular property and ADMET (absorption, distribution, metabolism, excretion, and toxicity) of the synthesized compounds were predicted by using Molinspiration and PreADMET online servers, respectively. It can be concluded that the lead AChEI compound 5g presented satisfactory drug-like characteristics and ADME properties.

60 APPLIED LIFE SCIENCES↗

Green synthesis, molecular docking, anti-oxidant and anti-inflammatory activities of α-aminophosphonates

The naturally viable α-amino acid surrogates have been synthesised via Kabachnik–Fields reaction by the condensation of 2-aminothiazole with various aldehydes and dialkyl phosphites in the presence of Caffeine hydrogen sulfate (CHS) as eco-friendly and reusable catalyst under microwave irradiation and solvent-free conditions. The title compounds were characterised by IR, {sup 1}H, {sup 13}C, {sup 31}P NMR and mass spectral data. All the synthesised (4a–j) compounds were screened for their insilico and in vitro studies. The results revealed that, out of all the titled compounds 4a, 4e, 4h and 4i have exhibited significant activity in terms of antioxidant and anti-inflammatory activity. In addition, molecular docking studies were also carried out against Cox-2 with celocoxib as the standard. .

60 APPLIED LIFE SCIENCES↗

Antiaging activity, molecular docking, and prediction of percutaneous absorption parameters of quinoline–hydrazone hybrids

The application of antiaging agents can contribute to the prevention and control of skin photoaging. In the current research, nine quinoline–hydrazone hybrids were synthesized to obtain biologically active compounds as possible antiaging agents. The compounds were tested through a comprehensive in vitro evaluation of antielastase, anticollagenase, and antihyaluronidase activities along with the determination of their potential to quench reactive oxygen species (ROS) by the ORAC method. The selected hybrids were subsequently tested on human dermal fibroblasts (HDF) to reveal possible UVB photoprotective activity. The most potent antiaging protection of all the prepared compounds was shown by the trihydroxylated quinoline–hydrazones 5 and 9, which showed the best collagenase inhibition (IC{sub 50} = 39.4 and 45.6 µM, respectively). Compound 5 also showed activity against elastase and hyaluronidase (IC{sub 50} = 164.2 and 318.8 µM, respectively). The molecular docking results suggest that the difference of inhibition between 5 and 9 is principally attributed to the hydrogen bonds interactions in the residues His218 and His228, and Zn atom in collagenase, Val216 in elastase and Tyr75 in hyaluronidase. In addition, compounds 5 and 9 were able to significantly protect human skin cells from UVB radiation in vitro. These compounds significantly decreased UVB-induced MMP-1 and ROS production and inhibited the suppression of type I procollagen synthesis in cultured HDF. The in silico dermatopharmacokinetic parameters showed promising results. Therefore, our study presented promising results for antiaging drug discovery, focusing on quinoline–hydrazone hybrids as dual inhibitors of skin aging-related enzymes, antioxidants, and inhibitors of the biological effects of UVB irradiation.

60 APPLIED LIFE SCIENCES↗

Discovery of the Biginelli hybrids as novel caspase-9 activators in apoptotic machines: Lipophilicity, molecular docking study, influence on angiogenesis gene and miR-21 expression levels

In order to investigate potential therapeutically agents, novel products of Biginelli reaction (4a-l) were synthesized and exposed to cytotoxic and caspase activities, angiogenesis, cell cycle distribution, gene and microRNA expression levels, lipophilicity assessment and docking study. Among the twelve novel compounds (4a-l) evaluated for the cytotoxic activity, five of them (4c, 4d, 4f, 4k and 4l) that showed excellent activity on the tested cell lines (HeLa, LS174 and A549) were selected for further evaluation. Interestingly, compound 4f has up to three times higher selectivity index (SI) towards cancer cells than cisplatin (on HeLa, LS174 and A549 SI = 18.2, 13.5 and 11.2, respectively). The obtained results from cell cycle distribution and caspase activity indicate that tested compounds (4c, 4d, 4f, 4k and 4l) promoted caspase-9 activation, implicated in the intrinsic pathway of apoptosis. Lipophilicity of 4a-l was determinate by using reversed-phase high-performance liquid chromatography. © 2019 Elsevier Inc.

60 APPLIED LIFE SCIENCES↗

Synthesis, characterization, anticancer evaluation and mechanisms of cytotoxic activity of novel 3-hydroxy-3-pyrrolin-2-ones bearing thenoyl fragment: DNA, BSA interactions and molecular docking study

In order to make a progress in discovering a new agents for chemotherapy with improved properties and bearing in mind the fact that substituted 3-hydroxy-3-pyrrolin-2-ones belong to a class of biologically active compounds, series of novel 1,5-diaryl-4-(2-thienylcarbonyl)-3-hydroxy-3-pyrrolin-2-ones were synthesized and characterized by spectral (UV–Vis, IR, NMR, ESI-MS), X-ray and elemental analysis. All compounds were examined for their cytotoxic effect on human cancer cell lines HeLa and MDA-MB 231 and normal fibroblasts (MRC-5). Four compounds, 3-hydroxy-1-(p-tolyl)-4-(2-thienylcarbonyl)-5-(4-chlorophenyl)-2,5-dihydro-1H-pyrrol-2-one (D10), 3-hydroxy-1-(3-nitrophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D13), 3-hydroxy-1-(4-nitrophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D14), and 3-hydroxy-1-(4-chlorophenyl)-4-(2-thienylcarbonyl)-5-(4-(benzyloxy)phenyl)-2,5-dihydro-1H-pyrrol-2-one (D15), that showed the highest cytotoxicity against malignant cells and the best selectivity towards normal cells were selected for further experiments. Results obtained by investigating mechanisms of cytotoxic activity suggest that selected 3-hydroxy-3-pyrrolin-2-one derivatives in HeLa cells induce apoptosis that is associated with S phase arrest (D13, D15, and D10) or unrelated to cell cycle distribution (D14). Additionally, to better understand their suitability for potential use as anticancer medicaments we studied the interactions between biomacromolecules (DNA or BSA) and D13 and D15. The results indicated that D13 and D15 have great affinity to displace EB from the EB-DNA complex through intercalation [K sv = (3.7 ± 0.1) and (3.4 ± 0.1) × 10 3 M -1 , respectively], an intercalative mode also confirmed through viscosity measurements. K a values, obtained as result of fluorescence titration of BSA with D13 and D15 [K a = (4.2 ± 0.2) and (2.6 ± 0.2) × 10 5 M, respectively], support the fact that a significant amount of the tested compounds could be transported and distributed through the cells. In addition, by DNA and BSA molecular docking study for D13, D14 and D15 is determined and predicted the binding mode and the interaction region. © 2019 Elsevier Inc.

60 APPLIED LIFE SCIENCES↗

tinyIFD: A High-Throughput Binding Pose Refinement Workflow Through Induced-Fit Ligand Docking

A critical step in structure-based drug discovery is predicting whether and how a candidate molecule binds to a model of a therapeutic target. However, substantial protein side chain movements prevent current screening methods, such as docking, from accurately predicting the ligand conformations and require expensive refinements to produce viable candidates. Here, we present the development of a high-throughput and flexible ligand pose refinement workflow, called “tinyIFD”. The main features of the workflow include the use of specialized high-throughput, small-system MD simulation code mdgx.cuda and an actively learning model zoo approach. We show the application of this workflow on a large test set of diverse protein targets, achieving 66% and 76% success rates for finding a crystal-like pose within the top-2 and top-5 poses, respectively. We also applied this workflow to the SARS-CoV-2 main protease (M pro ) inhibitors, where we demonstrate the benefit of the active learning aspect in this workflow.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Formation of Linear Plasmonic Heterotrimers Using Nanoparticle Docking to DNA Origami Cages

The fabrication of complex assemblies with interesting collective properties from plasmonic nanoparticles (NPs) is often challenging. While DNA-directed self-assembly has emerged as one of the most promising approaches to forming such complex assemblies, the resulting structures tend to have large variability in gap sizes and shapes, as the DNA strands used to organize these particles are flexible, and the polydispersity of the NPs leads to variability in these critical structural features. Here, we use a new strategy termed docking to DNA origami cages (D-DOC) to organize spherical NPs into a linear heterotrimer with a precisely defined geometrical arrangement. Instead of binding NPs to the exterior of the DNA templates, D-DOC binds the NPs to either the interior or the opening of a 3D cage, which significantly reduces the variability of critical structural features by incorporating multiple diametrically arranged capture strands to tether NPs. Additionally, such a spatial arrangement of the capture strand can work synergistically with shape complementarity to achieve tighter confinement. To assemble NPs via D-DOC, we developed a multistep assembly process that first encapsulates an NP inside a cage and then binds two other NPs to the openings. Microscopic characterization shows low variability in the bond angles and gap sizes. Both UV–vis absorption and surface-enhanced Raman scattering (SERS) measurements showed strong plasmonic coupling that aligned with predictions by electrodynamic simulations, further confirming the precision of the assembly. These results suggest D-DOC could open new opportunities in biomolecular sensing, SERS and fluorescence spectroscopies, and energy harvesting through the self-assembly of NPs into more complex 3D assemblies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗