Crystals
·
2024
·Vol. 14
·期 12
·1104
·
IF 2.4
Xian-Rui Zhang,Bao-Lin Wu,Jing-Jing Han,Jin-Qing Li
Naproxen (NAP) is a non-steroidal anti-inflammatory drug (NSAID) that belongs to the arylpropionic acid class. Classified as a Biopharmaceutical Classification System (BCS) class II drug, NAP exhibits low water solubility, thus resulting in restricted oral bioavailability. This study aimed to evaluate the effectiveness of pharmaceutical salts in enhancing the solubility and oral bioavailability of NAP. Two novel NAP salts, specifically naproxen-ethylenediamine (NAP-EDA) and naproxen-trometamol (NAP-TRIS), were synthesized using a 2:1 and 1:1 stoichiometric ratio, respectively. The NAP-EDA and NAP-TRIS powders were thoroughly characterized using single-crystal X-ray diffraction (SXRD), powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC), providing a comprehensive understanding of their structural and thermal properties. Additionally, the solubilities and dissolution rates of NAP-EDA and NAP-TRIS salts were assessed in water and a pH 6.86 phosphate buffer. Notably, the solubility of NAP-TRIS salt increased markedly, by 397.5-fold in water and 6.2-fold at pH 6.86. Furthermore, in vivo pharmacokinetic studies in rats revealed that NAP-TRIS salt displayed faster absorption and higher peak blood concentrations compared to NAP. These results indicate that the NAP-TRIS salt effectively enhanced the solubility and oral bioavailability of naproxen. In conclusion, this study underscores the potential of pharmaceutical salts, particularly NAP-TRIS, in improving the solubility and oral bioavailability of drugs with low aqueous solubility, presenting a promising avenue for advancing drug delivery and therapeutic outcomes.
研究领域:
药学
·
药物递送系统
·
生物药剂学
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产品关联
DOI
高影响因子
CHIRALITY
·
2024
·Vol. 36
·期 5
·e23672
·
IF 2.8
Chen Chen,Yangfeng Peng,Yongming Wei,Mengyuan Liu,Yu Wang,Siqi Xiong,Huiyi Li,Quan He
Hydroxychloroquine (HCQ), 2-([4-([7-Chloro-4-quinolyl]amino)pentyl]ethylamino)ethanol, exhibited significant biological activity, while its side effects cannot be overlooked. The RP-HPLC enantio-separation was investigated for cost-effective and convenient optical purity analysis of HCQ. The thermodynamic resolution of Rac-HCQ, driven by enthalpy and entropy, was achieved on the C18 column using Carboxymethyl-β-cyclodextrin (CM-β-CD) as the chiral mobile phase agent (CMPA). The effects of C CM-β-CD , pH, and triethylamine (TEA) V% on the enantio-separation process were explored. Under the optimum conditions at 24°C, the retention times for the two enantiomers were t R 1 = 29.39 min $$ {t}_{R1}=29.39\ \min $$ and t R 2 = 32.42 min $$ {t}_{R2}=32.42\ \min $$ , resulting in R s = 1.87 $$ {R}_s=1.87 $$ . The resolution via diastereomeric salt formation of Rac-HCQ was developed to obtain the active pharmaceutical ingredient of single enantiomer S-HCQ. Di-p-Anisoyl-L-Tartaric Acid (L-DATA) was proved effective as the resolution agent for Rac-HCQ. Surprisingly, it was found that refluxing time was a key fact affecting the resolution efficiency, which meant the kinetic dominate during the process of the resolution. Four factors—solvent volume, refluxing time, filtration temperature, and molar ratio—were optimized using the single-factor method and the response surface method. Two cubic models were established, and the reliability was subsequently verified. Under the optimal conditions, the less soluble salt of 2L-DATA:S-HCQ was obtained with a yield of 96.9% and optical purity of 63.0%. The optical purity of this less soluble salt increases to 99.0% with a yield of 74.2% after three rounds recrystallization.
研究领域:
药物化学
·
分析化学
·
制药工程
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产品关联
DOI
PubMed
高影响因子
NORDIC PULP & PAPER RESEARCH JOURNAL
·
2019
·Vol. 35
·期 1
·18-24
·
IF 0.929
Hailong Li,Chao Du,Shujuan Ge,Mengru Liu
This study aimed to investigate the oxalate formation mechanism during chlorine dioxide (
ClO
2
) bleaching of bamboo kraft pulp, and thus explore favourable
ClO
2
bleaching conditions to better control oxalate formation. The amount of oxalate formed varied linearly with
ClO
2
dosage within the whole research range, while it rose exponentially within the first 90 mins of pulp bleaching. Then the actual bleaching process was simulated by reacting
ClO
2
with three representative lignin model compounds and comparatively studied. The rule of oxalate formation in the simulated reaction system was identical to that in pulp bleaching by
ClO
2
, except for oxalate production by veratraldehyde with prolonged reaction time. Under identical conditions, vanillin formed the highest amount of oxalate, while veratraldehyde formed the least. Furthermore, the amount of oxalate formed increased by 19.59 mg/kg when the kappa number of the delignified pulp was reduced by one unit. Considering the satisfactory pulp brightness and decreased oxalate formation, the recommended conditions for
ClO
2
bleaching of bamboo kraft pulp were a
ClO
2
dosage of 4 %, 60 °C and 70 mins.
研究领域:
制浆造纸工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Environmental Science-Nano
·
2019
·Vol. 7
·期 1
·327-338
·
IF 7.704
Tao Wang,Yangyang Liu,Yue Deng,Hanyun Cheng,Yang Yang,Kejian Li,Xiaozhong Fang,Liwu Zhang
Atmospheric photochemistry is widely regarded as an important pathway for SO2 oxidation. The influence of irradiation intensity, especially photochemistry under weak sunlight during heavy haze events is not known. This work investigates the irradiation-intensity-dependence of the dust-related heterogeneous process using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ex situ flow reaction. Illumination of the particles alters the surface oxygen species, and further accelerates the significant oxidation of sulfite species to sulfate products. The sulfate formation rate grows rapidly from the dark state to faint irradiation, while it becomes insensitive to irradiation intensity variation under strong illumination. According to the photo-electrochemical tests and concentration dependence experiments, this interesting phenomenon can be interpreted by the presence of excess SO2 under weak sunlight and sufficient photoinduced active species (PAS) under strong illumination. This uneven promotion effect is beneficial for explaining the sulfate burst under faint sunlight during heavy haze events. More significantly, the uptake of SO2 accounts for the increase of acidic species and the decrease of adsorbed water on the particle surface, thus elevating the particle acidity. Under these circumstances, the dissolution of zinc oxide (ZnO) takes place, and results in diverse principal products varying with the illumination condition, e.g. ZnSO3 under weak sunlight while ZnSO4 under strong irradiation. In general, photochemistry has profound impacts on atmospheric sulfur cycling, as well as the cycle of metal elements. The irradiation intensity dependent effects imply the raising uncertainty in the current air quality models.
研究领域:
环境科学
·
大气化学
✓ 已验证
DOI
高影响因子
npj Climate and Atmospheric Science
·
2025
·Vol. 8
·期 1
·1-12
·
IF 8.4
Liu Yangyang,Li Xiao,Ge Qiuyue,Fang Xiaozhong,Wang Tao,You Wenbo,Wang Wei,Xie Lifang,Li Kejian,Gong Kedong,Yang Le,Wang Runbo,Wang Jilun,Wang Licheng,Ma Minglu,Huang Tingting,Fu Hongbo,Chen Jianmin,Dong Xinyi,Zhang Liwu
Carbonate radical anion ( \({{\rm{CO}}}_{{3}^{.-}}\) ) is generally considered as a marginal intermediate that rarely regulates atmospheric-relevant reactions of significance. Unexpectedly, in this work, employing a suit of the in-field measurements, lab-based validations, improved kinetic numerical calculations, and chemical transport modeling, we demonstrate that \({{\rm{CO}}}_{{3}^{.-}}\) gives a significantly overlooked contribution (~54.4%) to overall secondary sulfate formation during dust storm-relevant episodes and ~236.3% increase of SO 2 uptake over mineral dust pathway during haze-relevant periods. GEOS-Chem modeling results further emphasize the important position of this radical ion in dust-driven SO 2 oxidation chemistry. Our finding leaves this active intermediate no longer a marginal oxidant currently prevailing in the framework of the atmospheric science community. More importantly, after considering this rapid dust-driven sulfate formation channel mediated by carbonate radicals during pollution episodes, this study provides a clear indication that high priority should be given to reducing alkaline soil dust emissions to achieve benefits for air quality.
研究领域:
大气科学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
Environmental Science-Nano
·
2021
·Vol. 8
·期 3
·698-710
·
IF 8.131
Kejian Li,Xiaozhong Fang,Tao Wang,Kedong Gong,Muhammad Ali Tahir,Wei Wang,Jin Han,Hanyun Cheng,Guanjun Xu,Liwu Zhang
Water-soluble low-molecular-weight dicarboxylic acids (DCAs) and corresponding salts are ubiquitous in the atmosphere. They could efficiently form chelates with iron in atmospheric particles, which could be photoexcited to generate a series of strong oxidants, and have profound impacts on atmospheric chemistry. However, the influences of iron–DCAs complexes on the heterogeneous uptake of atmospheric trace gases are unclear. In this study, the effects of dominant dicarboxylic acid salts (including oxalate, malonate, and succinate) on the heterogeneous SO2 conversion with hematite nanoparticles were systematically investigated using film flow reaction and in situ DRIFTs experiments. It was found that a trace amount of DCA salts could significantly accelerate sulfate formation under solar light illumination. Additionally, similar results were also observed on the Arizona test dust, a proxy of authentic mineral dusts. Moreover, the iron solubility was increased owing to the effects of oxalate complexation, especially under light irradiation. Furthermore, the reaction mechanisms for the enhanced SO2 uptake and iron dissolution in the presence of DCA salts were proposed, and atmospheric environmental implications were discussed.
研究领域:
环境科学
·
大气化学
✓ 已验证
DOI
高影响因子
GREEN CHEMISTRY
·
2025
·
IF 9.2
Changhui Jing,Falin Li,Shuai Du,Xin Wang,Fengyuan Zhang,Songqi Ma
One-component epoxy resins have captured great attention due to their improved processing, environmental friendliness, quality stability, etc., but developing green and high-latent-efficiency ones is still urgent required. In this work, a bio-derived, high-latent-efficiency accelerator was facilely synthesized via Michael addition reaction of an abundant bioresource itaconic acid and imidazole. To confirm the latent mechanism, another accelerator without carboxyl group was synthesized from dimethyl itaconate and imidazole, and used together with imidazole as the controls. The chemical structures of the two synthesized accelerators were characterized in detail by FTIR, 1H NMR, 13C NMR and TOF-MS spectra. The latent and curing behavior of the one-component epoxy resins from bisphenol A epoxy, dicyandiamide and accelerators were studied by DSC and rheology, and the results showed that itaconic acid-modified imidazole systems possess long storage life at room temperature of above 210 days and can be cured rapidly at elevated temperatures. Otherwise, the imidazole system and dimethyl itaconate-modified imidazole system have short storage life below 1 day and 8 days, respectively. The excellent latent efficiency of itaconic acid-modified imidazole (IAIM) was attributed to the synergistical inhibit of the reactivity of imidazole toward epoxy groups through the steric-hindrance effect from the main structure of itaconic acid and the salt-formation effect from the carboxyl groups of itaconic acid. This work provides a green and simple strategy to synthesize high-efficiency latent curing accelerator.
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
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Yangyang Liu,Tao Wang,Xiaozhong Fang,Yue Deng,Hanyun Cheng,Aziz-Ur-Rahim Bacha,Iqra Nabi,Liwu Zhang
The rapid sulfate formation is a crucial factor determining the explosive growth of fine particles and the frequent occurrence of severe haze events in China. Recent field observations also show that brown carbon is one of the most critical components in aerosol particles sampled during haze episodes. To this day, there is limited knowledge that accesses the role of brown carbon in atmospheric chemistry . In fact, these carbonaceous particulate matters , mainly derived from forest fires, biomass burning , and biogenic release, can act as photosensitizers and produce varieties of active intermediates to alter oxidation capacity. Experimental results in this work provide evidence that hydroxyl radical (∙OH) stems from brown carbon proxies fulvic acid /humic acid (FA/HA) upon irradiation, leading to rapid SO 2 oxidation on brown carbon particles in the atmosphere. Further correlation analyses for sulfate formation and chromophore properties of 12 model compounds demonstrate that brown carbon particles with higher aromaticity and E 2 /E 3 (the ratio of absorbance at 254 nm to that at 365 nm) would facilitate ∙OH production and SO 2 photo-oxidation. Uptake coefficient measurements and sulfate production rate estimation indicate that brown carbon could gain importance in atmospheric SO 2 oxidation. A better understanding of SO 2 uptake kinetics on brown carbon surfaces favors in defining new regulations to improve air quality and reduce the harmful effects of haze events on resident health and the environment.
研究领域:
大气科学
·
环境化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2023
·
IF 5.8
Qiang Huang,Zhiren Zou,Xiaobo Li,Qinwen Xiao,Guang Liang,Wenqi Wu
The drug-amino acid co-amorphous systems and amorphous solid dispersions (ASDs) are promising methods to address the poor water solubility of poorly water-soluble drugs. However, some amino acids might not be perfect co-formers for co-amorphous systems, and the relatively low drug-loading of many ASDs is one of the main disadvantages of ASDs. Thus, poly- l -lysine and polyglutamic acid were selected as the co-formers, ball milled with basic mebendazole, neutral tadalafil and acidic valsartan at different weight ratios (from 3:1 to 1:3) to prepare poly (amino acid)-based ASDs, aiming to combine the advantages of co-amorphous systems (high drug-loading) and ASDs (relatively high T g and high physical stability). All the mixtures were converted into amorphous after milling. The powder dissolution studies showed that drug-poly (amino acid) ASDs improved the dissolution rate of the drug in different ways and to different degrees. Moreover, the two poly (amino acid)s enhanced the physical stability of amorphous drugs. It is worthy to mention that the salt formation between the drug and the poly (amino acid) does not necessarily mean better performance compared to non-salt forming systems, and salt formation is also not a prerequisite for the formation of promising drug-poly (amino acid) ASDs.
研究领域:
药剂学
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2024
·
IF 4.2
Chunyan Zhang,Qingxin Ma,Peng Zhang,Tianzeng Chen,Yonghong Wang,Biwu Chu,Hao Li,Jikun Li,Chuncheng Chen,Jincai Zhao,Hong He
As the main source of atmospheric sulfate aerosol , the aqueous-phase oxidation of SO 2 has been of great concern. Traditionally, the aqueous-phase oxidation of SO 2 is considered a consumption process of atmospheric oxidation capacity; however, we report here that •OH radicals and other reactive oxygen species (ROS) can be generated in the photochemical reactions of bulk HSO 3 − solution. This •OH production pathway results in the fast sulfate formation in the photooxidation of dissolved SO 2 . The photochemical process is determined to be pH-dependent in which sulfate formation is promoted by decreasing pH. Hence, a light - driven acidic positive feedback mechanism is proposed that the oxidation of dissolved SO 2 and the formation of •OH radicals have a synergistic promoting effect. These results indicate that the photochemistry of dissolved SO 2 could be a missing source of aqueous •OH radicals as well as sulfate at regional to global scales.
研究领域:
大气科学
·
环境化学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2017
·
IF 6.942
Guangsen Xia,Yujue Wang,Bin Wang,Jun Huang,Shubo Deng,Gang Yu
Previous studies indicate that effective generation of hydrogen peroxide (H 2 O 2 ) from cathodic oxygen (O 2 ) reduction is critical for the improved water treatment performance (e.g., enhanced pollutant degradation and reduced bromate formation) during the electro-peroxone (E-peroxone) process (a combined process of electrolysis and ozonation). However, undesired reactions (e.g., O 3 , H 2 O 2 , and H 2 O reductions) may occur in competition with O 2 reduction at the cathode. To get a better understanding of how these side reactions would affect the process, this study investigated the cathodic reaction mechanisms during electrolysis with O 2 /O 3 gas mixture sparging using various electrochemical techniques (e.g., linear sweep voltammetry and stepped-current chronopotentiometry). Results show that when a carbon brush cathode was used during electrolysis with O 2 /O 3 sparging, H 2 O and H 2 O 2 reductions were usually negligible cathodic reactions. However, O 3 can be preferentially reduced at much more positive potentials (ca. 0.9 V vs. SCE) than O 2 (ca. −0.1 V vs. SCE) at the carbon cathode. Therefore, cathodic O 2 reduction was inhibited when the process was operated under current limited conditions for cathodic O 3 reduction. The inhibition of O 2 reduction prevented the desired E-peroxone process (cathodic O 2 reduction to H 2 O 2 and ensuing reaction of H 2 O 2 with O 3 to OH) from occurring. In contrast, when cathodic O 3 reduction was limited by O 3 mass transfer to the cathode, cathodic O 2 reduction to H 2 O 2 could occur, thus enabling the E-peroxone process to enhance pollutant degradation and mineralization. Many process and water parameters (applied current, ozone dose, and reactivity of water constituents with O 3 ) can cause fundamental changes in the cathodic reaction mechanisms, thus profoundly influencing water treatment performance during the E-peroxone process. To exploit the benefits of H 2 O 2 in water treatment, reaction conditions should be carefully controlled to promote cathodic O 2 reduction during the E-peroxone process.
研究领域:
环境科学
·
电化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science Bulletin
·
2025
·
IF 21.1
Ziyan Guo,Pengxiang Qiu,Huan Song,Can Ye,Yaning Du,Keding Lu
The mechanisms that produce atmospheric sulfate, a critical PM 2.5 constituent, must be elucidated to inform air quality interventions. Current evidence indicates that manganese-catalyzed heterogeneous SO 2 oxidation is a dominant sulfate source. We demonstrate that black carbon (BC) critically enhances this process through interfacial electronic interactions with HSO 3 − /SO 3 2− species, reducing SO 2 oxidation barriers while increasing reactive oxygen species (ROS) generation ( 1 O 2 , •O 2 − , and •OH). Unique sulfur isotopic signatures measured in BC-Mn 2+ /O 2 systems confirm a novel oxidation pathway in which BC facilitates electron transfer during O 2 -activated SO 2 conversion. Multiphase modeling revealed that under typical haze conditions, BC-mediated catalysis produces sulfate at higher rates than traditional Mn-only pathways. The synergistic BC–Mn system enables continuous redox cycling via O 2 activation, establishing BC as an active electronic modulator rather than a passive substrate in sulfate formation. These findings redefine the role of BC in atmospheric chemistry, offering a molecular basis for targeted sulfate aerosol control.
研究领域:
大气化学
·
环境科学
·
气溶胶化学
·
表面催化
·
分子地球化学
·
空气污染控制
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）