ACS Central Science最新文献

{"title":"Late-Stage Minimal Labeling of Peptides and Proteins for Real-Time Imaging of Cellular Trafficking.","authors":"Ferran Nadal-Bufi, Raj V Nithun, Fabio de Moliner, Xiaoxi Lin, Shaimaa Habiballah, Muhammad Jbara, Marc Vendrell","doi":"10.1021/acscentsci.4c01249","DOIUrl":"10.1021/acscentsci.4c01249","url":null,"abstract":"<p><p>The cellular uptake routes of peptides and proteins are complex and diverse, often handicapping therapeutic success. Understanding their mechanisms of internalization requires chemical derivatization with approaches that are compatible with wash-free and real-time imaging. In this work, we developed a new late-stage labeling strategy for unprotected peptides and proteins, which retains their biological activity while enabling live-cell imaging of uptake and intracellular trafficking. Benzo-2,1,3-thiadiazoles were selectively incorporated into Cys residues of both linear and cyclic peptides via Pd-mediated arylation with good yields and high purities. The resulting labeled peptides are chemically stable under physiological conditions and display strong fluorogenic character for wash-free imaging studies. We utilized this approach to prepare native-like analogues of cell-penetrating peptides and performed time-course analysis of their internalization routes in live cells by fluorescence lifetime imaging. Furthermore, we applied our strategy to label the chemokine protein mCCL2 and monitor its internalization via receptor-mediated endocytosis in live macrophages. This study provides a straightforward strategy for late-stage fluorogenic labeling of intact peptides and small proteins and direct visualization of dynamic intracellular events.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"11 1","pages":"66-75"},"PeriodicalIF":12.7,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758221/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recycling of Post-Consumer Waste Polystyrene Using Commercial Plastic Additives.","authors":"Sewon Oh, Hanning Jiang, Liat H Kugelmass, Erin E Stache","doi":"10.1021/acscentsci.4c01317","DOIUrl":"10.1021/acscentsci.4c01317","url":null,"abstract":"<p><p>Photothermal conversion can promote plastic depolymerization (chemical recycling to a monomer) through light-to-heat conversion. The highly localized temperature gradient near the photothermal agent surface allows selective heating with spatial control not observed with bulk pyrolysis. However, identifying and incorporating practical photothermal agents into plastics for end-of-life depolymerization have not been realized. Interestingly, plastics containing carbon black as a pigment present an ideal opportunity for photothermal conversion recycling. Herein, we use visible light to depolymerize polystyrene plastics into styrene monomers by using the dye in commercial black plastics. A model system is evaluated by synthesizing polystyrene-carbon black composites and depolymerizing under white LED light irradiation, producing styrene monomer in up to 60% yield. Excitingly, unmodified postconsumer black polystyrene samples are successfully depolymerized to a styrene monomer without adding catalysts or solvents. Using focused solar irradiation, yields up to 80% are observed in just 5 min. Furthermore, combining multiple types of polystyrene plastics with a small percentage of black polystyrene plastic enables full depolymerization of the mixture. This simple method leverages existing plastic additives to actualize a closed-loop economy of all-colored plastics.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"11 1","pages":"57-65"},"PeriodicalIF":12.7,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11758496/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143044857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trap States in Reduced Colloidal Titanium Dioxide Nanoparticles Have Different Proton Stoichiometries.","authors":"Noreen E Gentry, Noah J Gibson, Justin L Lee, Jennifer L Peper, James M Mayer","doi":"10.1021/acscentsci.4c01074","DOIUrl":"10.1021/acscentsci.4c01074","url":null,"abstract":"<p><p>Added electrons and holes in semiconducting (nano)materials typically occupy \"trap states,\" which often determine their photophysical properties and chemical reactivity. However, trap states are usually ill-defined, with few insights into their stoichiometry or structure. Our laboratory previously reported that aqueous colloidal TiO₂ nanoparticles prepared from TiCl₄ + H₂O have two classes of electron trap states, termed <b>Blue</b> and <b>Red</b>. Herein, we show that the formation of <b>Red</b> from oxidized TiO₂ requires 1<i>e</i> ^- + 1H⁺, while <b>Blue</b> requires 1<i>e</i> ^- + 2H⁺. The two states are in a protic equilibrium, <b>Blue</b> ⇌ <b>Red</b> + H⁺, with <i>K</i> _eq = 2.65 mM. The <b>Blue</b> states in the TiO₂ NPs behave just like a soluble molecular acid with this <i>K</i> _eq as their <i>K</i> _a, as supported by solvent isotope studies. Because the trap states have different compositions, their population and depopulation occur with the making and breaking of chemical bonds and not (as commonly assumed) just by the movement of electrons. In addition, the direct observation of a 2H⁺/1<i>e</i> ^- trap state contradicts the emerging H atom transfer (1H⁺/1<i>e</i> ^-) paradigm for oxide/solution interfaces. Finally, this work emphasizes the importance of chemical stoichiometries, not just electronic energies, in understanding and directing the reactivity at solid/solution interfaces.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2266-2273"},"PeriodicalIF":12.7,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672544/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Regiospecific Co-Assembly Method to Functionalize Ordered Mesoporous Metal Oxides with Customizable Noble Metal Nanocrystals.","authors":"Jichun Li, Lingxiao Xue, Yu Deng, Xiaowei Cheng, Junhao Ma, Wenhe Xie, Meihua Chen, Yonghui Deng","doi":"10.1021/acscentsci.4c01592","DOIUrl":"10.1021/acscentsci.4c01592","url":null,"abstract":"<p><p>An efficient regiospecific co-assembly (RSCA) strategy is developed for general synthesis of mesoporous metal oxides with pore walls precisely decorated by highly dispersed noble metal nanocrystals with customized parameters (diameter and composition). It features the rational utilization of the specific interactions between hydrophilic molecular precursors, hydrophobic noble metal nanocrystals, and amphiphilic block copolymers, to achieve regiospecific co-assembly as confirmed by molecular dynamics simulations. Through this RSCA strategy, we achieved a controllable synthesis of a variety of functional mesoporous metal oxide composites (e.g., WO₃, ZrO₂, TiO₂) with in-pore walls precisely decorated by various noble metal nanocrystals of tailored components (Au, Ag, Pt, Pd and their nanoalloys) and sizes (3.0-8.5 nm). As an example, the obtained mesoporous 0.5-Ag/WO₃ material has a highly interconnected mesoporous structure and uniform 6.5 nm Ag nanocrystals confined in the mesopores, showing superior NO sensing performances with high sensitivity, good selectivity, and stability at low working temperature (127 °C). <i>In situ</i> spectroscopy study indicates that the NO sensing process involves a unique gas-solid reaction, where NO molecules are converted into chemisorbed NO _<i>x</i> species over the sensitive materials, inducing a remarkable change of resistance and outputting a dramatic response signal.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2274-2284"},"PeriodicalIF":12.7,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672546/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bespoke and Accessible Electrochemical Reactors","authors":"Charlotte E. Willans*,&nbsp;","doi":"10.1021/acscentsci.4c0179410.1021/acscentsci.4c01794","DOIUrl":"https://doi.org/10.1021/acscentsci.4c01794https://doi.org/10.1021/acscentsci.4c01794","url":null,"abstract":"<p >User-friendly software that allows scientists to design, print, test, and iterate upon reactors enables key reactor parameters to be optimized for electrochemical reactions.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 11","pages":"2000–2002 2000–2002"},"PeriodicalIF":12.7,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acscentsci.4c01794","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142719498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bespoke and Accessible Electrochemical Reactors.","authors":"Charlotte E Willans","doi":"10.1021/acscentsci.4c01794","DOIUrl":"10.1021/acscentsci.4c01794","url":null,"abstract":"","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 11","pages":"2000-2002"},"PeriodicalIF":12.7,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11613255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrophilic Ethylene Glycol Fragments: A Determinant Affecting the Therapeutic Index of Paclitaxel Prodrug Nanoassemblies.","authors":"Yaqi Li, Yixin Sun, Qing Wang, Shuo Wang, Cuiyun Liu, Yuetong Huang, Wenxin Zhong, Xiyan Wang, Wenjing Wang, Shiyi Zuo, Xianbao Shi, Xiaohui Pu, Jin Sun, Zhonggui He, Bingjun Sun","doi":"10.1021/acscentsci.4c01004","DOIUrl":"10.1021/acscentsci.4c01004","url":null,"abstract":"<p><p>Prodrug-based nanoassemblies are promising platforms for cancer therapy. Prodrugs typically consist of three main components: drug modules, intelligent response modules, and modification modules. However, the available modification modules are usually hydrophobic aliphatic side chains, which affect the activation efficiency of the prodrugs. Herein, hydrophilic ethylene glycol fragments were inserted between the modification modules and the response modules, and the important effects of hydrophilic fragments on the assembly, drug release, and therapeutic index of the prodrugs were investigated. Notably, the introduction of hydrophilic fragments affected the intermolecular forces of the prodrugs and increased the interaction of hydrogen bonding. In addition, hydrophilic fragments significantly improved the redox drug release profiles, which affected the therapeutic index of the prodrug nanoassemblies. PTX-SS-OA NPs with hydrophilic fragments exhibited increased redox sensitivity, enhanced cytotoxicity, and superior antitumor efficacy. In comparison, PTX-SS-OAL NPs without hydrophilic fragments showed limited redox sensitivity and cytotoxicity but displayed better safety. Overall, the hydrophilic fragment is a critical determinant in modulating the therapeutic index of the prodrug nanoassemblies, which contributes to the development of advanced prodrug nanodelivery systems.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2253-2265"},"PeriodicalIF":12.7,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672549/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combination of Coevolutionary Information and Supervised Learning Enables Generation of Cyclic Peptide Inhibitors with Enhanced Potency from a Small Data Set.","authors":"Ylenia Mazzocato, Nicola Frasson, Matthew Sample, Cristian Fregonese, Angela Pavan, Alberto Caregnato, Marta Simeoni, Alessandro Scarso, Laura Cendron, Petr Šulc, Alessandro Angelini","doi":"10.1021/acscentsci.4c01428","DOIUrl":"10.1021/acscentsci.4c01428","url":null,"abstract":"<p><p>Computational generation of cyclic peptide inhibitors using machine learning models requires large size training data sets often difficult to generate experimentally. Here we demonstrated that sequential combination of Random Forest Regression with the pseudolikelihood maximization Direct Coupling Analysis method and Monte Carlo simulation can effectively enhance the design pipeline of cyclic peptide inhibitors of a tumor-associated protease even for small experimental data sets. Further <i>in vitro</i> studies showed that such <i>in silico</i>-evolved cyclic peptides are more potent than the best peptide inhibitors previously developed to this target. Crystal structure of the cyclic peptides in complex with the protease resembled those of protein complexes, with large interaction surfaces, constrained peptide backbones, and multiple inter- and intramolecular interactions, leading to good binding affinity and selectivity.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2242-2252"},"PeriodicalIF":12.7,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672547/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding Oxygen-Induced Reactions and Their Impact on n-Type Polymeric Mixed Conductor-Based Devices.","authors":"Prem D Nayak, Büsra Dereli, David Ohayon, Shofarul Wustoni, Tania Cecilia Hidalgo Castillo, Victor Druet, Yazhou Wang, Adel Hama, Craig Combe, Sophie Griggs, Maryam Alsufyani, Rajendar Sheelamanthula, Iain McCulloch, Luigi Cavallo, Sahika Inal","doi":"10.1021/acscentsci.4c00654","DOIUrl":"10.1021/acscentsci.4c00654","url":null,"abstract":"<p><p>Electron transporting (n-type) polymeric mixed conductors are an exciting class of materials for devices with aqueous electrolyte interfaces, such as bioelectronic sensors, actuators, and soft charge storage systems. However, their charge transport performance falls short of their p-type counterparts, primarily due to electrochemical side reactions such as the oxygen reduction reaction (ORR). To mitigate ORR, a common strategy in n-type organic semiconductor design focuses on lowering the lowest unoccupied molecular orbital (LUMO) level. Despite empirical observations suggesting a correlation between deep LUMO levels, low ORR, and enhanced electrochemical cycling stability in water, this relationship lacks robust evidence. In this work, we delve into the electrochemical reactions of n-type polymeric mixed conductors with varying LUMO levels and assess the impact of ORR on charge storage performance and organic electrochemical transistor (OECT) operation. Our results reveal a limited correlation between LUMO levels and ORR currents, as well as the electrochemical operational stability of the films. While ORR currents minimally contribute to OECT channel currents under fixed biasing conditions, n-type films self-discharge rapidly at floating potentials in a capacitor-like configuration. The density functional theory analysis, complemented by X-ray photoelectron spectroscopy, underscores the critical role of backbone chemistry in controlling O₂-related degradation pathways and device performance losses. These findings highlight the persistent challenge posed by ORR in n-type semiconductor design and advocate for shifting the focus toward exploring chemical moieties with limited O₂ interactions to enhance operational stability and performance at n-type film/water interfaces.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2229-2241"},"PeriodicalIF":12.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672553/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecularly Designed and Nanoconfined Polymer Electronic Materials for Skin-like Electronics.","authors":"Yu-Qing Zheng, Zhenan Bao","doi":"10.1021/acscentsci.4c01541","DOIUrl":"10.1021/acscentsci.4c01541","url":null,"abstract":"<p><p>Stretchable electronics have seen substantial development in skin-like mechanical properties and functionality thanks to the advancements made in intrinsically stretchable polymer electronic materials. Nanoscale phase separation of polymer materials within an elastic matrix to form one-dimensional nanostructures, namely nanoconfinement, effectively reduces conformational disorders that have long impeded charge transport properties of conjugated polymers. Nanoconfinement results in enhanced charge transport and the addition of skin-like properties. In this Outlook, we highlight the current understanding of structure-property relationships for intrinsically stretchable electronic materials with a focus on the nanoconfinement strategy as a promising approach to incorporate skin-like properties and other functionalities without compromising charge transport. We outline emerging directions and challenges for intrinsically stretchable electronic materials with the aim of constructing skin-like electronic systems.</p>","PeriodicalId":10,"journal":{"name":"ACS Central Science","volume":"10 12","pages":"2188-2199"},"PeriodicalIF":12.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11672543/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142902404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}