ABSTRACT
Broadband infrared (IR) absorption is sought after for wide range of applications. Graphene can support IR plasmonic waves tightly bound to its surface, leading to an intensified near-field. However, the excitation of graphene plasmonic waves usually relies on resonances. Thus, it is still difficult to directly obtain both high near-field intensity and high absorption rate in ultra-broad IR band. Herein, a novel method is proposed to directly realize high near-field intensity in broadband IR band by graphene coated manganous oxide microwires featured hierarchical nanostructures (HNSs-MnO@Gr MWs) both experimentally and theoretically. Both near-field intensity and IR absorption of HNSs-MnO@Gr MWs are enhanced by at least one order of magnitude compared to microwires with smooth surfaces. The results demonstrate that the HNSs-MnO@Gr MWs support vibrational sensing of small organic molecules, covering the whole fingerprint region and function group region. Compared with the graphene-flake-based enhancers, the signal enhancement factors reach a record high of 103 . Furthermore, just a single HNSs-MnO@Gr MW can be constructed to realize sensitively photoresponse with high responsivity (over 3000 V W-1 ) from near-IR to mid-IR. The graphene coated dielectric hierarchical micro/nanoplatform with enhanced near-field intensity is scalable and can harness for potential applications including spectroscopy, optoelectronics, and sensing.
ABSTRACT
Saponin is an essential natural compound in purple yams with high nutritional and medicinal value. In this work, a multitemplate molecule-imprinted polymer (MMIP) was synthesized with dioscin, protodioscin, and diosgenin templates. The MMIPs were characterized with scanning electron microscopy, thermogravimetric analysis, Brunauer-Emmett-Teller (BET) adsorption, and Fourier transform infrared spectroscopy. The efficacy of the MMIPs was assessed with static, dynamic, selective adsorption, desorption, and reusability experiments. The three saponins were selectively extracted and determined by MMIP-high-performance liquid chromatography. The polymer morphology was regular and spherical. The amount of the MMIP adsorbed was 74.825 mg/g, and the imprinting factor was 2.1. The MMIP adsorbed the three saponins from purple yam extract, with recovery rates of 95.5-103.43 % and desorption rates of 85 %-98 %. In addition, the MMIPs were reused at least six times. These results demonstrated that the MMIPs efficiently and selectively extracted dioscin, protodioscin, and diosgenin from food matrices at high rates.
Subject(s)
Dioscorea , Diosgenin/analogs & derivatives , Molecular Imprinting , Saponins , Molecularly Imprinted Polymers , Molecular Imprinting/methods , Polymers/chemistry , Adsorption , Chromatography, High Pressure Liquid/methods , Solid Phase Extraction/methodsABSTRACT
The extraction of active ingredients from traditional Chinese medicine has received considerable attentions. In this study, 16 kinds of natural deep eutectic solvent (NADES) with ultrasonic were selected to extract saponins from purple yam root and the extraction mechanism was investigated. The results showed that chloride/acrylic acid (1:2; n/n) had the highest extraction yield for saponins. The optimal extraction process parameters were 24% water content, 20 mL/g liquid-solid ratio, and ultrasonic extraction for 85 min (81 °C, 600 W). The extraction rate (ER) of purple yam saponins was 0.935%, close to the fitted result of 96.5 mg/g. Molecular dynamics simulations and FT-IR results showed that the NADES may extract the saponin constituents from purple yam through hydrogen bonding. Compared with traditional extraction methods and molecularly imprinted polymer methods, NADES has a higher ER and lower cost (1.53 $/g), which provides a reference for subsequent industrial quantitative production.
Subject(s)
Deep Eutectic Solvents , Dioscorea , Saponins , Saponins/chemistry , Saponins/isolation & purification , Dioscorea/chemistry , Deep Eutectic Solvents/chemistry , Ultrasonics , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Permeability , Chemical Fractionation/methods , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/isolation & purification , Plant Roots/chemistryABSTRACT
Acute lymphoblastic leukemia (ALL) is the most common type of cancer in children. Despite good remission rate has achieved nowadays, the patients still face a substantial risk of relapse. It has long been recognized that thiopurines are critical components in the treatment for prevention of recurrence in childhood ALL, the 6-mercaptopurine (6-MP) has usually been used in daily long-term maintenance therapy, and 6-thioguanine (6-TG) limited to the reinforcement of therapy. However, there is no optimal regimen for 6-TG or 6-MP. The related research advances on the clinical effectiveness of the two thiopurines are reviewed.
Subject(s)
Mercaptopurine/therapeutic use , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Thioguanine/therapeutic use , Child , HumansABSTRACT
OBJECTIVE: To observe the clinical effects of scraping therapy on perimenopausal syndrome. METHODS: Twenty women with perimenopausal syndrome were treated with scraping therapy and the dorsal course of the Governor Vessell and the Urinary Bladder Meridian of Foot-Taiyang were scraped, especially on the Back-shu points and Ashi points. The clinical symptoms were observed and compared with a modified Kupperman score before and after treatment. RESULTS: In all the 20 patients, 3 cases were cured, 6 cases were markedly effective, 9 cases were effective, 2 cases were ineffective, and the total effective rate was 90.0%. The Kupperman total score after treatment of (10.4 +/- 7.5) was significantly lower than the score before treatment of (25.0 +/- 5.3) (P < 0.001), in which, hot flushes and sweating, insomnia, fatigue, paresthesia, anxiety/irritability, hypaphrodisia, urinary system infection, tinnitus, dizziness, memory deterioration and headache were eased significantly (P < 0.001, P < 0.05). CONCLUSION: The scraping therapy has a good clinical effect on perimenopausal syndrome and can significantly improve the clinical symptoms.
Subject(s)
Acupuncture Points , Dizziness/therapy , Hot Flashes/therapy , Medicine, Chinese Traditional/methods , Perimenopause/physiology , Female , Humans , Meridians , Middle Aged , Sweating , Treatment OutcomeABSTRACT
Two extracellular polysaccharides, ENP1 and ENP2, were isolated from the fermentation liquid of the marine fungus Epicoccum nigrum JJY-40 by anion-exchange chromatography and gel-filtration chromatography, and their structures were investigated using chemical and spectroscopic methods including methylation analysis and NMR spectroscopy. The results demonstrated that ENP1 was composed of mannose, glucose, and galactose in the molar ratio of 5.0:2.1:1.0, and the main chain of the polysaccharide consisted of (1 â 2)-linked mannose, (1 â 3)-linked mannose, terminal mannose, (1 â 6)-linked glucose, (1 â 4)-linked glucose, and (1 â 4)-linked galactose. ENP2 was composed of mannose, galactose, glucose, and glucuronic acid in a molar ratio of 12.4:11.2:8.3:1.0, and its glycosidic linkage patterns included terminal mannose, (1 â 6)-linked glucose, (1 â 4)-linked galactose, and (1 â 3)-linked mannose. The two polysaccharides had a partially branched structure with branch point located at C-3 position of (1 â 6)-linked glucose residue. The molecular weights of ENP1 and ENP2 were 19.2 kDa and 32.7 kDa, respectively. Antioxidant properties of the two polysaccharides were evaluated with hydroxyl, superoxide, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities and lipid peroxidation inhibition in vitro, and results showed that ENP2 and ENP1 had good antioxidant activities, especially ENP2. ENP2 could be effective as a potential antioxidant.