Chemical Science最新文献

{"title":"Enhanced Reactivity at the Oil-Water Interface Accelerates the Synthesis of Zymonic Acid in Microemulsions","authors":"Brandon J. Wallace, Musarrat Makhnun, Rana Bachnak, Pyeongeun Kim, Musahid Ahmed, Cari S. Dutcher, Kevin Roger Wilson, Ashok Ajoy","doi":"10.1039/d5sc03258j","DOIUrl":"https://doi.org/10.1039/d5sc03258j","url":null,"abstract":"Chemical reactions in microscale compartments, such as aerosols and emulsions, can exhibit significantly faster reaction rates relative to macroscale containers. This enhancement in chemistry is often due to the elevated importance of surfaces as reaction vessels are reduced to picoliter volumes. While most studies have focused on the air-water interface of droplets, there are comparably fewer studies of reactions in micron-scale aqueous solutions encapsulated by oil. Here we investigate the condensation reaction of pyruvic acid (PA) to form zymonic acid (ZA) and water. Using microfluidics and optical trapping, chemical kinetics are measured in monodisperse micron-sized emulsions <em>in-situ</em> via Raman spectroscopy. Relative to a macroscopic bulk solution, which exhibits little to no reaction over many days, we find efficient production of ZA over the same time period. A kinetic model is developed to elucidate the role of the interface in accelerating the microdroplet reaction kinetics. After quantifying the surface partitioning of PA from interfacial tension measurements, the rate coefficient for the condensation reaction at the oil-water interface is determined to be 1.8 x 10<small>^-2</small> M<small>^-1</small> s<small>^-1</small>. This rate coefficient is estimated to be 10<small>⁵</small> larger than the reaction rate in bulk aqueous solutions. Compared to previous studies of accelerated ZA formation at the air-water interface on nanodroplets, we find that the reaction at the oil-water interface is 20 times more efficient. Despite this difference, the overall ZA formation rate in emulsions is significantly slower than in the same-sized aerosols, which arises from the weaker partitioning of PA to the oil-aqueous relative to air-water interface. These results highlight the interplay between interfacial partitioning and reactivity in accelerating chemistry in microcompartments and provides new insights into how interfacial composition influences condensation reactions.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"153 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144640422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitric Oxide-Activatable NIR-II Organic Small Molecule for Fluorescence Imaging-Guided Synergistic Photodynamic and Photothermal Therapy","authors":"Xinyi Zhang, Ling Li, Yuxin Ren, Meiqi Li, Xinyi Ma, Yajie Long, Junqing Wang, Yanli Tang","doi":"10.1039/d5sc03636d","DOIUrl":"https://doi.org/10.1039/d5sc03636d","url":null,"abstract":"Precise cancer diagnosis and treatment are vital to reducing mortality. The development of activatable second near-infrared window (NIR-II) imaging-guided tumor phototherapy strategies with excellent tumor specificity and antitumor effects remains a major challenge. In this work, we design and synthesize a D-π-A-π-D organic small molecule CTBA that can be effectively activated by nitric oxide. CTBA possesses the absorption and emission in the visible region. Interestingly, after reacting with excess nitric oxide in the tumor microenvironment, the probe can be converted into CTBT with a new structure, which exhibits excellent NIR-II fluorescence, photodynamic and photothermal properties under 808 nm excitation. Notably, this activatable probe pioneers the convergence of three critical features: (1) NIR-II imaging capacity for deep-tissue visualization, (2) on-demand therapeutic activation, and (3) synergistic photodynamic-photothermal effects, marking the first report of such an integrated system. By virtue of its \"turn-on\" property, this probe significantly reduces the background noise of imaging and the damage to normal tissues during phototherapy. Then, CTBA-NPs are constructed by self-assembly between CTBA and PS1000-PEG2000, which can achieve highly accurate and efficient tumor diagnosis and treatment in vitro and in vivo. This work provides a promising strategy for designing activatable multifunctional NIR-II fluorescent probes for precise theranostics.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"37 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Characterisation of Photoactivatable and Lysine Reactive o-Nitrobenzyl Alcohol-Based Crosslinkers","authors":"Adam Cahill, Martin Walko, Benjamin Fenton, Sri Ranjani Ganji, Anne Herbert, Sheena E. Radford, Nikil Kapur, Keith Livingstone, Megan H Wright, Antonio Calabrese","doi":"10.1039/d5sc03211c","DOIUrl":"https://doi.org/10.1039/d5sc03211c","url":null,"abstract":"Photoreactive groups are invaluable tools in structural proteomics, offering reagent-free activation and temporal control of protein labelling. However, traditional UV-activatable functional groups often produce unstable intermediates and diverse products, making these chemistries difficult to deploy at scale. In this study, we performed a systematic analysis of <em>ortho</em>-nitrobenzyl alcohol (<em>o</em>NBA) reactivity for integration into novel reagents for chemical crosslinking-mass spectrometry. <em>o</em>NBA photochemistry represents a promising alternative to traditional photoactivatable crosslinkers due to its unique specificity towards lysine residues. Here, we synthesised two molecules comprising <em>o</em>NBA functional groups with different substituents and assessed their labelling efficiency against a model protein. To ensure high labelling yields while maintaining a short irradiation time, we constructed a high power 365 nm irradiation device which improves the efficiency of <em>o</em>NBA photolysis. Our studies identified an amide-substituted probe that labels proteins with high efficiency. We next incorporated this optimised <em>o</em>NBA moiety into a homo-bifunctional crosslinker and a hetero-bifunctional crosslinker in combination with an NHS ester, which both resulted in high yields of crosslinked products. Our findings highlight that optimised <em>o</em>NBA-based reactive groups are viable UV-activated warheads that can deliver high labelling yields and efficient protein crosslinking, unlocking a wealth of potential structural proteomics applications.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"7 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulating Ultralong Room-Temperature Phosphorescence Through Mechanical Confinement of Tailored Polymer/MOF Hybrid Interfaces","authors":"Samraj Mollick, Vishal Kachawal, Benjamin Hupp, Yogeshwar D. More, Michele Tricarico, Andreas Steffen, Jin-Chong Tan","doi":"10.1039/d5sc03727a","DOIUrl":"https://doi.org/10.1039/d5sc03727a","url":null,"abstract":"Achieving ultra-long room temperature phosphorescence (RTP) remains a significant challenge due to the inherent trade-off between excited-state lifetime and photoluminescence quantum yield (QY). Herein, we report the synthesis of polymer/metal-organic framework (MOF) hybrids via a bottom-up approach, enabling the formation of direct covalent integration between polymer matrices and MOF structures. By systematically optimizing the incorporation of long-chain alkyl amines during the synthesis process, the resultant hybrids demonstrate green RTP performance, achieving a lifetime of 359 milliseconds (ms) at room temperature (592 ms at 77 K), and a phosphorescence QY of ~ 28%, whereas no detectable phosphorescent is observed in the parent MOFs and polymer components. Notably, nanoindentation-based mechanical analysis reveals, for the first time, a clear relationship between increased matrix rigidity and enhanced RTP performance. Additionally, a detailed investigation highlights the pivotal roles of extensive intramolecular hydrogen bonding and covalent linking between polymer and extended frameworks in stabilizing triplet states, enabling efficient RTP. The hybrid materials also demonstrate good processability, allowing the creation of flexible RTP-emissive fibers and films (lifetime of 408 ms at RT and 613 ms at 77 K) that leverage their inherent flexibility. Furthermore, these hybrids exhibit good selectivity in detecting water over other alcohols, underscoring their potential for smart sensor applications.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"17 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"2D-to-3D transformations of a covalent organic framework via post-synthetic crosslinking","authors":"Garrison A. Bauer, Mercedes K. Taylor","doi":"10.1039/d5sc02492g","DOIUrl":"https://doi.org/10.1039/d5sc02492g","url":null,"abstract":"Two-dimensional (2D) covalent organic frameworks (COFs) are easier to synthesize and functionalize than their three-dimensional (3D) counterparts, but the 2D frameworks lack stability due to weak non-covalent interactions that maintain the layered structure. Herein, we provide a post-synthetic strategy to covalently crosslink the independent sheets of 2D COFs while preserving the crystallinity and porosity of the materials. The crosslinked frameworks show greatly enhanced mechanical stability compared to the parent 2D frameworks, retaining more than 90% of the original Brunauer–Emmett–Teller (BET) surface area when subjected to extensive sonication or grinding. Further, crosslinking enables the reduction of the imine linkages with sodium borohydride while preserving crystallinity and porosity, which has yet to be shown for 2D COFs. Finally, the imine linkages on a crosslinked framework were first reduced and then reacted with an acyl chloride, establishing a general approach to framework functionalization. This post-synthetic crosslinking approach stabilizes 2D frameworks and opens access to amine linkages in these materials, thus increasing hydrolytic stability and potential functionalization as selective adsorbents.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"2 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Femtosecond Real-Time Fragmentation Dynamics of Nitrobenzene Anion Reveal the Dissociative Electron Attachment Mechanism","authors":"sejun an, Jun Won Choi, Junggil Kim, Dabin Kim, Sang Kyu Kim","doi":"10.1039/d5sc03656a","DOIUrl":"https://doi.org/10.1039/d5sc03656a","url":null,"abstract":"The femtosecond real-time dynamics of the nitrobenzene anion (C₆H₅NO₂⁻) in the excited state have been investigated using a recently developed time-resolved photofragment depletion (TRPD) spectroscopic technique, providing molecular-level insight into the C–N bond dissociation pathway leading to ·C₆H₅ and NO₂⁻ fragments for the first time. Ultrafast electronic relaxation from the D₂ state, prepared at 2.48 eV, to the ground state (D₀) is followed by statistical unimolecular dissociation, yielding NO₂⁻ with a lifetime (τ) of approximately 294 ps. This behavior stands in stark contrast to the prompt bond rupture typically observed in conventional dissociative electron attachment (DEA) processes, offering deep insight into the energy flow that governs anionic bond dissociation following electron–molecule collisions.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"670 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current Status and Future Perspectives of Low-Temperature Electrolytes for Supercapacitors","authors":"Changde Ma, Pratteek Das, Xiaoyu Shi, Feng Zhou, Zhong-Shuai Wu","doi":"10.1039/d5sc03933a","DOIUrl":"https://doi.org/10.1039/d5sc03933a","url":null,"abstract":"Supercapacitors are critical for high-power applications due to their fast charge-discharge capabilities and long lifespans. However, achieving high performance at ultra-low temperatures remains a significant challenge, limiting their use in extreme environments. The electrolyte responsible for ion transport is the key factor governing the low-temperature performance of supercapacitors. In this perspective, we focus on the recent advances in low-temperature electrolytes for supercapacitors. We first introduce the critical physical parameters for evaluating low-temperature electrolyte. Then, we emphasize the key design strategies for low-temperature electrolytes, followed by a detailed discussion of their anti-freezing mechanisms, encompassing aqueous, organic, ionic liquid, and gel-based electrolytes. Additionally, particular emphasis is placed on the theoretical simulation and advanced characterization techniques, given their capability to elucidate the microscopic structure of the electrolyte and provide comprehensive insights into its energy storage mechanism. Finally, we have provided an outlook on the current challenges and future development directions of low-temperature electrolytes, which is expected to offer promising strategies for reliable, high-performance supercapacitors in ultra-low temperature applications.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"72 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Base-Promoted Dynamic Amide Exchange: Efficient Access to Isotopically Enriched Tertiary Amides","authors":"Quentin Lemesre, Rémi Blieck, Antoine Sallustrau, Timothee D'Anfray, Frederic Taran, Davide Audisio","doi":"10.1039/d5sc02566d","DOIUrl":"https://doi.org/10.1039/d5sc02566d","url":null,"abstract":"Amide isotope labeling is a crucial tool in drug discovery and development. However, current methods label the desired peptide bond in a multi-step fashion. This study presents novel strategies for amide isotope exchange through transamidation and amide metathesis. By optimizing reaction conditions and exploring substrate scope, we achieved direct labeling of both amine and carbonyl moieties. These findings pave the way for more sustainable isotope labeling technologies. Furthermore, preliminary examples of isotope-containing waste recycling demonstrate a crucial step towards a greener future for isotope chemistry.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"385 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uncovering Intramolecular Singlet Fission at the Root of the Dual Fluorescence of 1,4-Bis(p-nitro-β-styryl)benzene in Solution","authors":"Letizia Mencaroni, Alexandr Zaykov, Benedetta Carlotti, Fausto Elisei, Guillaume Bastien, Raimondo Germani, Zdenek Havlas, Anna Spalletti, Josef Michl","doi":"10.1039/d5sc03612g","DOIUrl":"https://doi.org/10.1039/d5sc03612g","url":null,"abstract":"The exploration of singlet fission (SF) promises a pathway to many leaps forward including more efficient solar energy extraction and, more recently, organic-based quantum computing. Our study, through a joint experimental and computational approach, revolves around 1,4-bis(p-nitro-β-styryl)benzene (<strong>1</strong>) as the smallest molecule where the intramolecular transformation of the initially allowed 1<small>¹</small>Bu singlet state to the 2<small>¹</small>Ag excited state stops being ordinary internal conversion and becomes the first half of the SF process. Herein, we experimentally observe explicit breaking of Kasha rule. Using femtosecond broadband fluorescence upconversion, we measure a dual fluorescence of <strong>1</strong> in solution from its two lowest singlet excited states of different symmetry. Femtosecond transient absorption (TA) and fluorescence upconversion spectroscopy of <strong>1</strong> in toluene reveal ultrafast (17±5 ps), almost quantitative interconversion between 1<small>¹</small>B and 2<small>¹</small>A states. A sensitization bracketing experiment with ns-TA is used to analyze the T<small>₁</small> state of <strong>1</strong>. Employing high-level ab initio extended multi-configuration quasi-degenerate 2nd-order perturbation theory (XMCQDPT2) calculations, we accurately model ground- and excited-state potential energy surfaces. 1<small>¹</small>B states are predominantly described by ordinary HOMO–LUMO excitation. 2<small>¹</small>A states can be projected in localized frontier molecular orbitals as intramolecular strongly coupled triplet biexciton [<small>¹</small>(T<small>₁</small>T<small>₁</small>)] with the inclusion of intramolecular charge-transfer states. Moreover, the experimental resemblance of 2<small>¹</small>A and T<small>₁</small> absorption is elucidated. Fluorescence temperature-dependence experiment further corroborates the XMCQDPT2 model accurate prediction of the 1<small>¹</small>B and 2<small>¹</small>A low barrier of crossing (ca. 600 cm<small>^-1</small>). Concentration-dependent experiment shows a dramatic increase in triplet yield: up to 200% yield is confirmed by both ns-TA quantitative measurements and detailed analysis of the fs-TA data. All the obtained results suggest the occurrence of a SF mechanism for the triplet production: intramolecular <small>¹</small>(T<small>₁</small>T<small>₁</small>) formation followed by intermolecular triplet separation aided by entropy and spatial separation.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"94 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Creating Hydrophobic Nanopockets in Metal–Organic Frameworks to Promote Lignin Derivatives Hydrodeoxygenation at Ambient Condition","authors":"Yan Liang, Hongru Zhou, Yuanxia Zhao, Xiaoyu Liang, Zhiwei Chen, Min Ji, Min Wang","doi":"10.1039/d5sc04236d","DOIUrl":"https://doi.org/10.1039/d5sc04236d","url":null,"abstract":"The construction of homogeneous-like reaction environments in the vicinity of heterogeneous active sites is an effective artificial means to recapitulate the catalytic activity of natural enzymes. In this work, we fabricated hydrophobic nanopockets in metal–organic frameworks (MOFs) and confined Pd nanoclusters in them to mimic the joint action of metal centers and proximal cofactors in enzyme catalysis. The hydrophobic microenvironment of the MOF pore was introduced by the functional group (-CH3) modification on the organic linkers, which provide noncovalent interactions for substrate enrichment and ultimately create homogeneous-like conditions for the catalyst to exert its intrinsic activity. The obtained Pd@UIO-66-CH3 composites with enhanced hydrophobic interaction exhibited a high catalytic performance of lignin-derived aromatic alcohols/aldehydes hydrodeoxygenation at ambient conditions. This work elucidates the importance of the microenvironment around the active site in catalysis and provides new ideas for designing artificial enzyme catalytic systems with substrate-specific recognition.","PeriodicalId":9909,"journal":{"name":"Chemical Science","volume":"3 1","pages":""},"PeriodicalIF":8.4,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}