Journal of Materials Chemistry C
·
2025
·Vol. 13
·期 7
·3193-3198
·
IF 5.1
Yamei Ding,Mingyu Xie,Ping He,Ziqi Zhao,Huiwen Lin,Li Tao
Wide-bandgap quantum dots (QDs) have recognized as the third generation of low-dimensional semiconductors with reliable optical response, outstanding stability and biocompatibility for long-term biosensing in health care applications, especially in extreme environments. However, the applicable scenarios are limited, because optical switching over a large span from the wide bandgap (deep UV region) to the visible region is challenging due to the stable framework and the high breakdown difficulty. In this work, we adopted a facile protonation/deprotonation treatment process, which is suitable for different biogenic environments, to modulate the one-photon and two-photon fluorescence of wide-bandgap QDs. Two fluorescent centers are coordinative to control one-photon emission from deep blue (410 nm) to yellow (585 nm) emission with a wide large-span modulation, superior to most reports under different acid–base environments. The electron transition between electron-donating amine (–NH2) groups and H+ (–OH) changes the degree of nonradiative transition, narrowing the breadth of the full width at half maximum (FWHM) by 34.4%. Moreover, our QDs exhibit two-photon fluorescence at 710 nm, which have never reported before for wide-bandgap nitrides. It shows pH-independent two-photon fluorescence because of the intrinsic electron–phonon coupling of the π-conjugated structure. This work introduces a simple design strategy to realize fluorescence control over a large span in wide-bandgap nanomaterials, enabling distensible applications in biological health and pH related linear or nonlinear optical fields.
研究领域:
纳米材料
·
生物传感
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·
IF 13.3
Hongzhi Zheng,Xing Tong,Yuping Zhang,Panchao Yin,Jiwang Yi,Zehong Chen,Haihong Lai,Wei zhou,Linxin Zhong,Hao Zhuo,Xinwen Peng
Nanofiber is the critical building block for many biological systems to perform various functions. Artificial assembly of molecules into nanofibers in a controllable and reversible manner will create “smart” functions to mimic those of their natural analogues and fabricate new functional materials, but remains an open challenge especially for nature macromolecules. Herein, the controllable and reversible assembly of nanofiber (CSNF) from natural macromolecules with oppositely charged groups are successfully realized by protonation and deprotonation of charged groups. By controlling the electrostatic interaction via protonation and deprotonation, the size and morphology of the assembled nanostructures can be precisely controlled. A strong electrostatic interaction contributes to large nanofiber with high strength, while poor electrostatic interaction produces finer nanofiber or nanoparticle. And especially, the assembly, disassembly, and reassembly of the nanofiber occurs reversibly through protonation and deprotonation, thereby paving a new way for precisely controlling the assembly process and structure of nanofiber. The reversible assembly allows the nanostructure to dynamically reorganize in response to subtle perturbation of environment. The as-prepared CSNF is mechanical strong and can be used as a nano building block to fabricate high-strength film, wire, and straw. This study offers many opportunities for the biomimetic synthesis of new functional materials.
研究领域:
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
·
2019
·
IF 3.202
Yunfeng Chai,Hongping Chen,Xin Liu,Chengyin Lu
The in-source collision-induced dissociation (CID) and MS/MS mass spectra of deprotonated tolfenpyrad and tebufenpyrad both showed an unusual fragment ion at m/z 187, but its fragmentation pattern and structure could not be explained by logical neutral losses. Accurate mass measurement indicated that the mass difference between this fragment ion and the dominant fragment ion at m/z 143 equaled to a carbon dioxide (CO2) molecule. The isolation of the fragment ion m/z 143 in the mass analyzer could spontaneously give rise to the ion m/z 187. The Gibbs free energy of carbon dioxide addition to deprotonated pyrazole ion was significantly negative from the computational results. According to these results, we derived a proposal for the formation and structure of the ion m/z 187, which was an attachment of molecular carbon dioxide to the fragment ion m/z 143 to produce a carboxylate anion. The trace carbon dioxide was speculated to be derived from the residual atmosphere or collision gas in the instrument. This study is valuable for the qualitative and quantitative mass spectrometry analysis of pesticides containing the pyrazole functional group.
研究领域:
分析化学
·
农药科学
·
质谱分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 9
·1-9
·
IF 5.479
Yue Qiaoli,Hu Yingying,Tao Lixia,Zhang Baoqian,Liu Chen,Wang Yongping,Chen Chunying,Zhao Jinsheng,Li Chen-Zhong
A fluorometric method is described for “turn-on” sensing of pH values via black phosphorus quantum dots (BPQD). Water-stable BPQD were synthesized by a liquid exfoliation method and characterized by TEM, FT-IR, XPS, and absorption and fluorescence spectra. The nanoparticles of BPQD have a uniform distribution with an average size of 5.2 nm. They exhibit bright green fluorescence, with excitation/emission maxima at 420/515 nm. The fluorescence of the BPQD is likely to arise from the quasi-molecular fluorophores of polycyclic aromatic compounds carrying P-P, P-O-P, and P x O y functions on its surface. The protonation and deprotonation of hydroxyl groups of BPQD causes a different degree of quenching of the BPQD. At pH values below 4.0, protons bind to BPQD to form non-fluorescent ground state complexes. At pH values above 4.0, the hydroxyl groups become deprotonated, and this induces the recovery of fluorescence. The sensor has a linear response in the pH range of 1.0–9.0. It was successfully applied to the determination of the pH values in human urine and serum samples.
Schematic representation of the preparation of black phosphorus quantum dots (BPQDs) from powdered BP crystals using liquid-phase exfoliation in N-methyl-2-pyrrolidone solution. The BPQDs display green fluorescence at high pH values but no fluorescence at very low pH values.
研究领域:
分析化学
·
纳米技术
·
材料科学
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2025
·
IF 2.9
Siyu Hou,Qin Yu,Xiaolan Cheng,Mengrong Hu,Zheng Li,Jian Luo
Chromophores incorporated into rigid polymer matrices may exhibit novel photophysical properties distinct from those in liquid solutions. In this work, we explored the decay path of the second ππ* state (2ππ*) of riboflavin in poly(vinyl alcohol) (PVA) solutions and films with various acidities. Highly efficient internal conversion from 2ππ* to the lowest ππ* state (1ππ*) induced by slight in-plane motion is demonstrated in all PVA solutions and films, irrespective of environmental acidity and rigidification. Ground-state protonation of riboflavin occurs in the highly acidic PVA film, and this cationic species emits fluorescence around 460 nm, in contrast to the ultrafast nonradiative relaxation in aqueous solution. The emission is demonstrated to originate from the 2ππ* state rather than the 1ππ* state. The 2ππ*-1ππ* internal conversion of protonated riboflavin is demonstrated to be induced by out-of-plane motion and impeded in a rigid PVA network, resulting in the anti-Kasha fluorescence.
研究领域:
化学
·
材料科学
·
光物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Jun Zhai,Quanfeng Wang,Qing Li,Bo Shang,Md. Hasibur Rahaman,Jialiang Liang,Jiucui Ji,Wenbo Liu
Carbamazepine (CBZ), a widely used antiepileptic drug, is refractory to biological wastewater treatment . Rapid removal of CBZ is possible using synthetic manganese oxide (δ-MnO 2 ) but the removal mechanisms require further investigation. In this study, CBZ degradation by δ-MnO 2 was carried out at different pH to further explore the degradation mechanisms. Results show that CBZ degradation by δ-MnO 2 was highly pH dependent, and rapid degradation occurred when pH <2.8. Based on the density functional theory calculations, increasing [H + ] not only increased the reactivity of δ-MnO 2 , but also enhanced the secondary reactions of the intermediates. During the degradation process, protonation of CBZ degradation intermediates, instead of CBZ, played an important role. The overall kinetics of CBZ degradation was then described by the retarded first-order model. The initial rate (r init ) in the model between pH 2.0 and 6.2 was determined to be r init = (2.41 ± 0.51) × 10 −3 [CBZ] 1.21 [MnO 2 ] 1.07 [H + ] 1.41 . This is the first report revealing that protonation of intermediates from CBZ degradation can improve the CBZ oxidation by δ-MnO2. The pathways of CBZ degradation by δ-MnO 2 were also proposed. The results of this study provide a new insight into the processing mechanism.
研究领域:
环境科学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Yuchen Tang,Xuqi Chen,Shaohua Zhang,Zachary J. Smith,Tingjuan Gao
Due to the fundamental mechanism of vibrational state transitions for chemical bonds, the spectra of Raman scattering are narrow-banded and photostable signals capable of probing specific reactions. In the case of protonation/deprotonation reactions, certain chemical bonds are broken and new bonds are formed. Based on the changes of the vibrational modes for the corresponding bonds, fingerprint analysis of multiple Raman bands may allow for the in situ visualization of proton distribution in live cells. However, Raman scattering faces the well-known challenge of low sensitivity. To perform the vibrational fingerprint analysis of Raman scattering by overcoming this challenge, we developed an azo-based resonance Raman pH probe. It was an azobenzene-featured small molecule responsive to protons with the inherent Raman signal ∼104-fold more intense than that of the conventional alkyne-type Raman reporter 5-ethynyl-2′-deoxyuridine. Through the substitution of the electron-donating and -withdrawing entities to the azobenzene group, the effect of resonance Raman scattering and fluorescence quenching was obtained. This effect resulted in a significant Raman enhancement factor of ∼103 compared to the counterpart molecules without the molecular design. Based on the enhanced Raman sensitivity of the azo-based resonance Raman pH probe, the identification of vibrational fingerprint changes at the azo group was achieved during the protonation/deprotonation reactions, and the vibrational fingerprint analysis resolved a pH difference of less than 0.2 unit. The method enabled sensitive hyperspectral cell imaging that clearly visualized the change of proton distribution in autophagic cells.
研究领域:
化学
·
生物物理
·
细胞生物学
·
光谱学
✓ 已验证
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
Bing Zhang,Yingxuan Li,Jianmin Luo,He Zhao,Jie Zhao,Guohui Dong,Yunqing Zhu,Chuanyi Wang
The SrBi 2 Nb 2 O 9 platelets with a thickness of about 600 nm were synthesized by molten salt synthesis method. The treatment of the SrBi 2 Nb 2 O 9 platelets with hydrochloric acid resulted in the formation of the protonated H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets. Through a top–down approach in ethylamine solution, the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets were exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets with a thickness of about 2.6 nm. The evolution of the structure, composition, morphology, optical, and photocatalytic properties of SrBi 2 Nb 2 O 9 platelets was studied as it is converted into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 platelets and subsequently exfoliated into H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets. The absorption edge shifts to a lower wavelength accompanied by the protonation and exfoliation. The photocatalytic H 2 evolution of the three samples were evaluated under the irradiation of a 300 W Xenon lamp from CH 3 OH/H 2 O solution, indicating that H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets Exhibit 5.5 and 26.2 times higher activity than that of the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 and SrBi 2 Nb 2 O 9 platelets, respectively. The enhanced activity for the H 1.78 Sr 0.78 Bi 0.22 Nb 2 O 7 nanosheets is mainly attributed to the higher separation efficiency of the photogenerated carriers and the larger specific surface area caused by the significant reduction in thickness.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Jirong Wang,Chengying Zhao,Shaojie Zhao,Xingmiao Lu,Mengyu Ma,Jinkai Zheng
The amidation of pectin by amino acids has been widely applied due to its safety and excellent gelling properties. This study systematically examined the effects of pH on the gelling properties of lysine-amidated pectin during amidation and gelation . Pectin was amidated over the range of pH 4–10, and the amidated pectin obtained at pH 10 showed the highest degree of amidation (DA, 27.0 %) due to the de-esterification, electrostatic attraction, and the stretching state of pectin. Moreover, it also exhibited the best gelling properties due to its greater numbers of calcium-binding regions (carboxyl groups) and hydrogen bond donors (amide groups). During gelation, the gel strength of CP (Lys 10) at pH 3–10 first increased and then decreased, with the highest gel strength at pH 8, which was due to the deprotonation of carboxyl groups, protonation of amino groups, and β-elimination. These results show that pH plays a key role in both amidation and gelation, with distinct mechanisms, and would provide a basis for the preparation of amidated pectins with excellent gelling properties. This will facilitate their application in the food industry.
研究领域:
食品科学
·
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2021
·
IF 4.076
Maolin Li,Mengwei Wang,Yumin Liu,Ruiling Ouyang,Mingdi Liu,Dandan Han,Junbo Gong
Furosemide (FUR) is usually used to treat congestive heart failure and edema. Although bioavailability problems exist due to its poor solubility and unstable gastrointestinal absorption, preparing FUR/amino acid (AA) co-amorphous systems is regarded as a promising way to solve this problem. In this work, the oscillating ball milling method was successfully used to prepare the co-amorphous systems of FUR with l-cysteine, l-phenylalanine (PHE), l-arginine, l-tryptophan (TRP), and l-valine. Protonation of the secondary amino group (N2) in FUR probably results in interactions with the AA carboxyl group, which lead to excellent compatibility between FUR and AAs. The co-amorphous systems formed between FUR and PHE/TRP possess higher physical stability than other FUR/AA co-amorphous systems, which may be attributed to favorable aromatic stacking in FUR/PHE and FUR/TRP systems. Additional experiments were performed to explore the impact of co-former loadings on the stability of co-amorphous systems, which revealed that the co-amorphous systems are most stable when the molar ratios are at 0.527 and 0.423 for FUR in FUR/PHE and FUR/TRP systems, respectively. Finally, powder dissolution tests of the FUR/PHE and FUR/TRP co-amorphous systems were carried out, and the results demonstrated that the selected most stable co-amorphous systems have excellent dissolution advantage with a two-fold improvement of dissolution rate compared to pure FUR.
研究领域:
药剂学
·
药物化学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Wen Hu,Zhiqiang Fang,Yu Liu,Yicong Zhou,Yudi Kuang,Honglong Ning,Bo Li,Gang Chen,Yingyao Liu
Marrying a randomly distributed network of wood fibers with sodium carboxymethyl cellulose (CMC-Na) by impregnation is a scalable method to prepare highly transparent and hazy (TH) paper with superior mechanical properties. However, the poor water resistance of this TH paper is a hindrance for its practical applications. In this study, a facile protonation process along with desalination is proposed to remove the above obstacle by reducing electrostatic repulsion among CMC molecular chains while strengthening the physical cross-linking among CMC molecular chains and also between CMC-H molecular chains and wood fibers in water. Consequently, the protonated TH paper not only presents an enhanced water resistance but also shows a negligible deterioration in optical and mechanical properties compared with the untreated TH paper. Moreover, the influence of the water resistance of various substrates (PET film, untreated TH paper, and protonated TH paper) on the electrical conductivity of inkjet-printed silver nanoparticle lines on them is investigated. We expect that such water resistant, transparent paper with high optical haze may open new avenues for the innovative application of paper and bring added value to existing products.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Fangyou Meng,Yuan Yu,Dongfeng Sun,Songmin Lin,Yangyang Chu,Wenhui Chu,Qingmei Su,Bingshe Xu
A novel PANI/Ni 2 P hybrid electrocatalyst with enhanced performance in hydrogen evolution reaction was explored. The current densities of the PANI/Ni 2 P hybrid electrocatalyst could achieve 10 mA cm −2 under much lower overpotential of 83 mV with a small Tafel slope of 69 mV dec −1 . This was due to the fact that nitrogen atoms in polyaniline had more isolated electrons, which could capture protons from hydrated ions to form protonated amino groups, thus accelerating the kinetics process of hydrogen evolution. Moreover, the current densities of the PANI/Ni 2 P hybrid electrocatalysts was only slightly attenuated after 5000 cycles, showing good stability and application potential of the PANI/Ni 2 P hybrid electrocatalysts. The effect of the thickness of the polyaniline layer on the performance of the PANI/Ni 2 P hybrid catalyst was fully discussed. This work also provided a new strategy to increase the catalytic activity of non-noble metal catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）