Although the parallel incorporation of fluorinated aromatic amino acids(FAAAs)into proteins has been explored since 2010,the corresponding ^(19)F NMR investigation has been lacking to date.To assess the potential of t...Although the parallel incorporation of fluorinated aromatic amino acids(FAAAs)into proteins has been explored since 2010,the corresponding ^(19)F NMR investigation has been lacking to date.To assess the potential of the parallel incorporation of FAAAs in studies of protein structure,dynamics and interactions,we examine the protein yields,fluorine incorporation efficiencies,and ^(19)F NMR spectra upon simultaneously incorporating FAAAs including 3-fluorotyrosine(3FY),4-fluorophenylalanine(4FF)and 5-fluorotryptophan(5FW)into two model proteins:the structured protein GB1 domain(GB1)and the intrinsically disordered protein a-synuclein(a-syn).We found that the simultaneous incorporation of 3FY and 5FW achieved higher efficiency than combinations of 4FF and 5FW,4FF and 3FY,or 3FY,4FF and 5FW.Moreover,incorporating more types of FAAAs leads to a reduction in overall yield.The ^(19)F spectra of 3FY,4FF and 5FW residues in α-syn and GB1 exhibited good dispersion of chemical shifts.However,the GB1 spectrum showed complexity due to incomplete fluorination and interactions within aromatic cluster.This complexity could be significantly reduced by supplementing the medium with natural aromatic amino acids.To validate the advantage of ^(19)F NMR spectrum,we use 3FY-4FF-5FW-F94W-α-syn to investigate the interaction between α-syn and sodium dodecyl sulphate(SDS)micelle.Our study demonstrates that ^(19)F NMR spectroscopy of proteins with parallel incorporation of FAAAs provides a valuable tool for investigating protein conformation,dynamics and interactions.展开更多
建立了核磁共振氟谱法测定氰化物的氟化衍生化合物1-氰基-2,2,2-三氟-1-苯乙基乙酸酯(CTPA)含量的方法。以乙酸3-氟苄酯为内标,采用5mm Auto XBB探头,探头温度298.2K,考察了不同浓度化合物的定量条件;通过比较化合物样品定量峰与内标物...建立了核磁共振氟谱法测定氰化物的氟化衍生化合物1-氰基-2,2,2-三氟-1-苯乙基乙酸酯(CTPA)含量的方法。以乙酸3-氟苄酯为内标,采用5mm Auto XBB探头,探头温度298.2K,考察了不同浓度化合物的定量条件;通过比较化合物样品定量峰与内标物质响应峰面积,计算化合物的含量。结果该化合物的19 F-NMR检测方法在0.5~50μg/mL具有良好的线性(r2=0.9966),该方法的定量限0.5μg/mL,检出限0.2μg/mL;同时考察了该化合物在不同浓度下的测量准确度。展开更多
Aqueous film-forming foams(AFFFs)are the primary source of toxic perfluoroalkyl and polyfluoroalkyl substances(PFAS)in wastewater.Thus,it is urgent to develop a facile and fast method for identifying fluorosurfactants...Aqueous film-forming foams(AFFFs)are the primary source of toxic perfluoroalkyl and polyfluoroalkyl substances(PFAS)in wastewater.Thus,it is urgent to develop a facile and fast method for identifying fluorosurfactants in commercially available AFFFs.In this work,fluorine nuclear magnetic resonance(^(19)F NMR)spectroscopy was optimized to measure AFFFs directly with the extra addition of 5%D_(2)O as the locking reagent,and high-quality spectra could be acquired within 4 min(0.1%fluorosurfactant content).Recovery experiments demonstrated that the use of different AFFFs had no marked influence on the quantitative analysis of fluorosurfactants.Such method works with low-field NMR spectroscopy(1.4 T)as well.Two-dimensional(2D)^(19)F COSY NMR was used to make signal assignments for different fluorosurfactant derivatives.The optimized ^(19)F NMR could quantify the commercially available fluorosurfactants in different AFFFs,identify them being in either the perfluorooctane sulfonate(PFOS)or fluorotelomer sulfonic acid(FTS)categories,and distinguish the head-group of PFOS and FTS derivatives,which exhibits great potentials in the developments of relevant commercial detections.展开更多
The present study aims to investigate the motional dynamics of risperidone within polylactic co-glycolic acid(PLGA)microsphere by employing solution state'H and 19F nuclear magnetic resonance(NMR)measurements.Risp...The present study aims to investigate the motional dynamics of risperidone within polylactic co-glycolic acid(PLGA)microsphere by employing solution state'H and 19F nuclear magnetic resonance(NMR)measurements.Risperidone,a second-generation fluorinated antipsychotic drug used for the treatment of schizophrenia is commercially marketed as PLGA microsphere formulation resulting in prolonged release of the drug in solution.Although the current trend in the pharmaceutical market is to develop drug formulation with long-acting release(LAR)products,complete physicochemical characterization of such formulations are scarce.Especially the effects of microsphere encapsulation on the motional properties and diffusion behavior of the drugs are not discussed adequately in any of the earlier reports.We therefore,have employed NMR relaxation and diffusion measurements to decipher the interaction of PLGA cavity water with risperidone.A detailed analysis of NMR relaxation rates confirmed the event of encapsulation and the presence of local motion in the non-fluorinated end of risperidone.Further,the relaxation data indicated a significant alteration in 19F chemical shift anisotropy(CSA)and CSA/dipole-dipole(DD)cross-correlated relaxation mechanism and decreased effect of solvent relaxation pointing out reduced water concentration within the microsphere cavity.'H and 19F diffusion coefficients of risperidone led to the information about hydrodynamic radius of risperidone in free and encapsulated states.Measurement of hydrodynamic radius supported the presence of limited water in PLGA cavity allowing higher translational mobility of risperidone after the encapsulation.展开更多
A novel and efficient method for distinguishing between chiral diols and diphenols has been established through the use of^(19)F NMR spectroscopy.Central to this system's efficacy is a chiral amine,strategically m...A novel and efficient method for distinguishing between chiral diols and diphenols has been established through the use of^(19)F NMR spectroscopy.Central to this system's efficacy is a chiral amine,strategically modified with a CF_(3)group.This amine reacts in-situ with 2-formylphenylboronic acid to create a chiral^(19)F-labeled probe.This probe demonstrates discriminatory capabilities by interacting with hydroxy-containing analytes to form boronic esters.These esters produce distinct^(19)F NMR signals that vary according to their stereoconfiguration,facilitating accurate chiral differentiation.The method's resolution capacity was demonstrated by successfully identifying 12 distinct chiral analytes(six pairs of enantiomers)in complex mixtures,highlighting its extensive potential in diverse chiral analysis applications.展开更多
基金supported by the Ministry of Science and Technology of China[grants 2021YFA1302602]the National Natural Science Foundation of China[grants 21925406,21991082,21921004]the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0540000 and YSBR-068).
文摘Although the parallel incorporation of fluorinated aromatic amino acids(FAAAs)into proteins has been explored since 2010,the corresponding ^(19)F NMR investigation has been lacking to date.To assess the potential of the parallel incorporation of FAAAs in studies of protein structure,dynamics and interactions,we examine the protein yields,fluorine incorporation efficiencies,and ^(19)F NMR spectra upon simultaneously incorporating FAAAs including 3-fluorotyrosine(3FY),4-fluorophenylalanine(4FF)and 5-fluorotryptophan(5FW)into two model proteins:the structured protein GB1 domain(GB1)and the intrinsically disordered protein a-synuclein(a-syn).We found that the simultaneous incorporation of 3FY and 5FW achieved higher efficiency than combinations of 4FF and 5FW,4FF and 3FY,or 3FY,4FF and 5FW.Moreover,incorporating more types of FAAAs leads to a reduction in overall yield.The ^(19)F spectra of 3FY,4FF and 5FW residues in α-syn and GB1 exhibited good dispersion of chemical shifts.However,the GB1 spectrum showed complexity due to incomplete fluorination and interactions within aromatic cluster.This complexity could be significantly reduced by supplementing the medium with natural aromatic amino acids.To validate the advantage of ^(19)F NMR spectrum,we use 3FY-4FF-5FW-F94W-α-syn to investigate the interaction between α-syn and sodium dodecyl sulphate(SDS)micelle.Our study demonstrates that ^(19)F NMR spectroscopy of proteins with parallel incorporation of FAAAs provides a valuable tool for investigating protein conformation,dynamics and interactions.
文摘建立了核磁共振氟谱法测定氰化物的氟化衍生化合物1-氰基-2,2,2-三氟-1-苯乙基乙酸酯(CTPA)含量的方法。以乙酸3-氟苄酯为内标,采用5mm Auto XBB探头,探头温度298.2K,考察了不同浓度化合物的定量条件;通过比较化合物样品定量峰与内标物质响应峰面积,计算化合物的含量。结果该化合物的19 F-NMR检测方法在0.5~50μg/mL具有良好的线性(r2=0.9966),该方法的定量限0.5μg/mL,检出限0.2μg/mL;同时考察了该化合物在不同浓度下的测量准确度。
基金financially supported by the“National Key R&D Program of China”(No.2022YFC3004900)“Basic Research Fund of TFRI”(No.2022SJ07)。
文摘Aqueous film-forming foams(AFFFs)are the primary source of toxic perfluoroalkyl and polyfluoroalkyl substances(PFAS)in wastewater.Thus,it is urgent to develop a facile and fast method for identifying fluorosurfactants in commercially available AFFFs.In this work,fluorine nuclear magnetic resonance(^(19)F NMR)spectroscopy was optimized to measure AFFFs directly with the extra addition of 5%D_(2)O as the locking reagent,and high-quality spectra could be acquired within 4 min(0.1%fluorosurfactant content).Recovery experiments demonstrated that the use of different AFFFs had no marked influence on the quantitative analysis of fluorosurfactants.Such method works with low-field NMR spectroscopy(1.4 T)as well.Two-dimensional(2D)^(19)F COSY NMR was used to make signal assignments for different fluorosurfactant derivatives.The optimized ^(19)F NMR could quantify the commercially available fluorosurfactants in different AFFFs,identify them being in either the perfluorooctane sulfonate(PFOS)or fluorotelomer sulfonic acid(FTS)categories,and distinguish the head-group of PFOS and FTS derivatives,which exhibits great potentials in the developments of relevant commercial detections.
文摘The present study aims to investigate the motional dynamics of risperidone within polylactic co-glycolic acid(PLGA)microsphere by employing solution state'H and 19F nuclear magnetic resonance(NMR)measurements.Risperidone,a second-generation fluorinated antipsychotic drug used for the treatment of schizophrenia is commercially marketed as PLGA microsphere formulation resulting in prolonged release of the drug in solution.Although the current trend in the pharmaceutical market is to develop drug formulation with long-acting release(LAR)products,complete physicochemical characterization of such formulations are scarce.Especially the effects of microsphere encapsulation on the motional properties and diffusion behavior of the drugs are not discussed adequately in any of the earlier reports.We therefore,have employed NMR relaxation and diffusion measurements to decipher the interaction of PLGA cavity water with risperidone.A detailed analysis of NMR relaxation rates confirmed the event of encapsulation and the presence of local motion in the non-fluorinated end of risperidone.Further,the relaxation data indicated a significant alteration in 19F chemical shift anisotropy(CSA)and CSA/dipole-dipole(DD)cross-correlated relaxation mechanism and decreased effect of solvent relaxation pointing out reduced water concentration within the microsphere cavity.'H and 19F diffusion coefficients of risperidone led to the information about hydrodynamic radius of risperidone in free and encapsulated states.Measurement of hydrodynamic radius supported the presence of limited water in PLGA cavity allowing higher translational mobility of risperidone after the encapsulation.
基金the National Key Research and Development Program of the Ministry of Science and Technology,People’s Republic of China(2016YFA0501203)the National Natural Science Foundation of China(31470727)+1 种基金the interdisciplinary medicine Seed Fund of Peking Universitythe 1000 Plan for Young Talent Program of China
基金supported by the National Key Research and Development Program(2021YFF0701700)the National Natural Science Foundation of China(22271305).
文摘A novel and efficient method for distinguishing between chiral diols and diphenols has been established through the use of^(19)F NMR spectroscopy.Central to this system's efficacy is a chiral amine,strategically modified with a CF_(3)group.This amine reacts in-situ with 2-formylphenylboronic acid to create a chiral^(19)F-labeled probe.This probe demonstrates discriminatory capabilities by interacting with hydroxy-containing analytes to form boronic esters.These esters produce distinct^(19)F NMR signals that vary according to their stereoconfiguration,facilitating accurate chiral differentiation.The method's resolution capacity was demonstrated by successfully identifying 12 distinct chiral analytes(six pairs of enantiomers)in complex mixtures,highlighting its extensive potential in diverse chiral analysis applications.
