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1.
以藏药诃子为原料,研制诃黎勒酸国家标准样品. 诃子经60%乙醇提取,大孔树脂富集,制备液相色谱技术得到诃黎勒酸标准品. 采用高效液相色谱(HPLC)、液相色谱-质谱(LC-MS)和薄层色谱(TLC)等手段进行纯度分析. 采用紫外光谱(UV)、红外光谱(IR)、高分辨质谱(MS)和核磁共振波谱(NMR)技术进行结构确认. 最后进行均匀性、稳定性和联合定值. 结果表明,诃黎勒酸样品均匀性良好,4 ℃储存,24个月内稳定. 联合定值确定诃黎勒酸纯度标准值为99.33%,符合国家标准品的要求. 研制出的诃黎勒酸(GSB 11-3724-2020)国家标准样品,可用于含量测定、检测方法评定、相关产品的检测与质量控制.  相似文献   

2.
蜂王浆冻干粉中甲硝唑残留标准样品制备的研究   总被引:2,自引:0,他引:2  
建立了蜂王浆冻干粉中甲硝唑残留标准样品的研制和定值方法。对日常检测阳性样品进行匀浆、冷冻干燥和均匀化加工处理,真空包装,得到1批400袋蜂王浆冻干粉样本。F检验法和t检验法表明在95%置信区间内,样本均匀性、短期稳定性和长期稳定性均达到标准样品要求。制备的甲硝唑标准样品采用液相色谱-串联质谱法,与国内外8家实验室进行协同定值。采用格拉布斯和柯克伦检验对定值结果进行异常值检验,并对结果进行不确定度评估。  相似文献   

3.
采用硅胶柱色谱和重结晶的方法制备姜黄素标准样品,用UV,IR,MS和NMR等方法对姜黄素标准样品进行结构鉴定,并进行了均匀性、稳定性检验。采用国内8家具有分析资质的实验室进行协同定值,并对定值结果的不确定度进行了评定。姜黄素标准样品的定值结果为99.78%,置信度95%的扩展不确定度(k=2)为0.13%。该姜黄素标准样品可用于有关姜黄素检测方法的校正和相关产品的质量控制。  相似文献   

4.
β-烟碱标准样品研制   总被引:1,自引:0,他引:1  
依据GB/T 15000标准样品工作导则,开展了β-烟碱国家标准样品研制工作。采用溶剂提取、萃取、柱色谱、水蒸汽蒸馏等方法制备β-烟碱样品,通过UV,IR,MS和NMR等方法对β-烟碱样品进行结构鉴定,并进行均匀性、稳定性检验。采用8家实验室进行联合定值,对定值结果进行数据分析。β-烟碱标准样品的均匀性和稳定性良好,定值结果为99.12%,置信度95%的扩展不确定度为0.64%。所制得的β-烟碱样品满足标准样品工作导则的要求,可用于有关烟草产品中β-烟碱的检测,以及相关产品的质量控制。  相似文献   

5.
6.
硫酸氨基葡萄糖标准样品的研制   总被引:1,自引:0,他引:1  
研制了硫酸氨基葡萄糖标准样品。以盐酸氨基葡萄糖为原料,制备高纯硫酸氨基葡萄糖,采用红外光谱(IR)、高分辨质谱和核磁共振谱(NMR)进行结构确证。样品分装成200瓶样品后,采用高效液相色谱–蒸发光散射法进行均匀性检验、稳定性检验和定值分析。从样品中随机抽取15瓶进行均匀性检验,结果表明在95%的置信区间范围内样品均匀性良好。按照25℃长期试验稳定性(12个月)进行稳定性考察,结果表明在考察期间内样品稳定性良好。标准样品经国内8家具有分析资质的实验室进行协同定值,硫酸氨基葡萄糖标准样品定值结果为99.84%,相对扩展不确定度为0.18%(k=1.96)。该标准样品达到国家标准样品的技术要求,可用于有关硫酸氨基葡萄糖的分析方法校正和质量控制。  相似文献   

7.
研制了章鱼肉碱标准样品。以章鱼加工副产物为原料,通过提取、分离纯化制备高纯章鱼肉碱,采用红外光谱(IR)、高分辨质谱(MS)和核磁共振谱(NMR)进行结构确证。样品分装成144瓶,采用离子色谱检测法进行均匀性、稳定性检验和定值分析。从样品中随机抽取15瓶进行均匀性检验,经F检验表明:在95%的置信区间内样品均匀性良好。在0~4℃条件下,经过24个月长期试验稳定性考察,结果表明样品稳定性良好。标准样品经国内8家具有分析资质的实验室进行协同定值,章鱼肉碱标准样品定值结果为99.49%,相对扩展不确定度为0.14%(k=1.96)。该标准样品达到标准样品的技术要求,可用于章鱼肉碱相关产品的质量控制和分析方法校正。  相似文献   

8.
二十碳四烯酸甲酯标准样品的研制   总被引:1,自引:0,他引:1  
依据GB/T 15000.3–2008工作导则,研制二十碳四烯酸甲酯标准样品。以二十碳四烯酸油粗品为原料,制备高纯二十碳四烯酸甲酯样品,通过红外、质谱、核磁等方法对二十碳四烯酸甲酯样品进行结构鉴定,并进行均匀性、稳定性检验。采用8家实验室进行联合定值,对定值结果进行数据分析。二十碳四烯酸甲酯标准样品均匀性和稳定性良好,其定值结果为99.28%,相对扩展不确定度为0.14%(k=2)。所制得的二十碳四烯酸甲酯样品满足标准样品工作导则的要求,可用于有关二十碳四烯酸甲酯的检测以及相关产品的质量控制。  相似文献   

9.
建立了蕨藻红素标准样品的研制方法。以总状蕨藻为原料,采用C18层析的方法,制备蕨藻红素单体,通过紫外吸收光谱、红外光谱、质谱和核磁共振等技术手段进行结构确证与表征。标准样品采用高效液相色谱法进行了均匀性、稳定性检验和8家实验室联合定值。结果表明,该样品在95%的置信区间范围均匀性良好;在25℃条件下可储存6天,在4℃条件下可储存24个月,稳定性良好;定值结果确定其纯度为98.64%,置信度95%的扩展不确定度为0.44%。该标准样品达到了GB/T 15000.3—2008规定的技术要求,具有溯源性,可用于含有蕨藻红素相关产品的质量控制和含量分析。  相似文献   

10.
以基础油为原料研制了二级粘度液标准物质,对其均匀性和稳定性进行了考察,用方差分析法进行了评价,用标准毛细管粘度计对其进行了定值。实验结果表明,该粘度液标准物质的均匀性良好,稳定性在1年以上,量值准确可靠,达到二级标准物质的技术指标要求。  相似文献   

11.
The search for a safe and effective inhibitor of ferroptosis, a recently described cell death pathway, has attracted increasing interest from scientists. Two hydrolyzable tannins, chebulagic acid and chebulinic acid, were selected for the study. Their optimized conformations were calculated using computational chemistry at the B3LYP-D3(BJ)/6-31G and B3LYP-D3(BJ)/6-311 + G(d,p) levels. The results suggested that (1) chebulagic acid presented a chair conformation, while chebulinic acid presented a skew-boat conformation; (2) the formation of chebulagic acid requires 762.1729 kcal/mol more molecular energy than chebulinic acid; and (3) the 3,6-HHDP (hexahydroxydiphenoyl) moiety was shown to be in an (R)- absolute stereoconfiguration. Subsequently, the ferroptosis inhibition of both tannins was determined using a erastin-treated bone marrow-derived mesenchymal stem cells (bmMSCs) model and compared to that of ferrostatin-1 (Fer-1). The relative inhibitory levels decreased in the following order: Fer-1 > chebulagic acid > chebulinic acid, as also revealed by the in vitro antioxidant assays. The UHPLC–ESI-Q-TOF-MS analysis suggested that, when treated with 16-(2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxazolidinyloxy free radicals, Fer-1 generated dimeric products, whereas the two acids did not. In conclusion, two hydrolyzable tannins, chebulagic acid and chebulinic acid, can act as natural ferroptosis inhibitors. Their ferroptosis inhibition is mediated by regular antioxidant pathways (ROS scavenging and iron chelation), rather than the redox-based catalytic recycling pathway exhibited by Fer-1. Through antioxidant pathways, the HHDP moiety in chebulagic acid enables ferroptosis-inhibitory action of hydrolyzable tannins.  相似文献   

12.
Abstract

Cis/trans isomers of ferulic and isoferulic acids and their corresponding coumarins, scopoletin and isoscopoletin, were separated by isocratic High Performance Liquid Chromatography using RP-8 (5 μm) as a stationary phase and aqueous methanol or aqueous acetonitrile as a mobile phase. The UV spectrum of cis-isoferulic acid was obtained by a photodiode array detector.  相似文献   

13.
Ravikanth  Kotagiri  Thakur  Mayank  Singh  Brijpal  Saxena  Mohanji 《Chromatographia》2009,69(5-6):597-599

Pongamia pinnata Linn. (Papilionaceae) seeds have gained great commercial and industrial importance owing to their high oil content. Presently, there is no appropriate TLC based method available for standardization of P. pinnata. A simple, robust and reproducible TLC method for the determination of Karanjin is reported in the seeds of P. pinnata. The method involves separation of components by TLC on pre-coated silica gel G 60 F254 plates developed on toluene: ethyl acetate (7:3 v/v) and detection at 260 nm in absorbance mode. The sensitivity of the method was found to be 100 ng. The linearity range was 50–300 ng. Four samples of P. pinnata from different geographical locations were tested for their karanjin content using the developed method. The proposed method was found to be robust, precise, and accurate, it therefore holds potential for detection, monitoring and quantification of karanjin in Pongamia pinnata.

  相似文献   

14.
非甾类抗炎性药物(NSAIDs)以其良好的消炎、解热和止痛等作用,广泛应用于人类疾病的治疗中.非甾类药物参与炎症治疗的同时不能被肝脏完全代谢,大部分母体化合物及其代谢物随人体排出.大量数据表明,在环境中残留的药物会直接或间接的以食品安全问题呈现出来,这成为分析化学、材料化学等诸多领域学科重点研究课题之一.由于NSAIDs的样品基质复杂,待分析组分种类繁多,目标分析物含量低,分析人员往往借助一些样品前处理技术来对其进行吸附与分离分析.总结了近年来非甾类抗炎性药物所呈现的问题,以及目前对环境中NSAIDs的多种分离检测技术,分离检测的核心是萃取材料的选择,并综述了近年来相关对NSAIDs有效吸附分离材料的研究进展,以及对优异吸附分离材料的展望.  相似文献   

15.
The reactions of 5-arylidene derivatives of Meldrum’s acid with ethyl vinyl ether or N-vinyl-2-oxazolidinone yielded trans-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, cis-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, or diastereoisomeric mixtures of pyrano[4,3-b]pyrans and reactions with 3,4-dihydro-2H-pyran afforded Michael adducts. The reactions of 5-arylidene derivatives of Meldrum’s acid with cyanoacetic acid derivatives do not provide appropriate pyrans.  相似文献   

16.
建立了一种同时检测中药材中齐墩果酸(OA)和熊果酸(UA)含量的超高效液相色谱串联质谱方法。采用超高效液相色谱-三级四极杆质谱(UPLC-TQMS)法对样品进行测定,Waters Acquity UPLC BEH C_(18)色谱柱(50 mm×2.1 mm,1.7μm)进行分离,以乙腈-5 mmol/L乙酸铵水溶液(氨水调至pH 9.24)为流动相,梯度洗脱;负离子模式下检测。结果表明,齐墩果酸和熊果酸在0.5~50.0 ng/mL浓度范围内线性关系良好,相关系数(r~2)分别为0.999 8和0.999 7;检出限(S/N=3)分别为0.006 6,0.012 8 ng/mL,定量下限(S/N=10)分别为0.002 0,0.003 8 ng/mL;对OA和UA进行加标回收实验,平均回收率分别为101.1%和100.8%,相对标准偏差(RSD,n=9)分别为1.8%和0.04%。对10种不同中药材中齐墩果酸和熊果酸含量进行检测,结果表明该方法快速简便、准确度高、重现性好,可用于含有齐墩果酸和熊果酸的中药材含量测定。  相似文献   

17.
A simple and inexpensive high performance capillary electrophoresis (HPCE) was applied to separate five benzoic acid compounds simultaneously. The investigation was carried out by micellar electrokinetic capillary chromatography (MECC). To avoid a time‐consuming and tedious procedure, orthogonal experimental design OA9 (34) for separation experiments was applied to find the optimal conditions in terms of the resolution and analytical time. The best conditions for separation were obtained using a 20 mM borax and 30 mM sodium dodecyl sulfate (SDS) buffer (pH 9.8) containing 2 mM β‐CD and 4% methanol (v/v). Online UV detection was performed at 250 nm. A voltage of 16 kV was applied and the temperature was controlled at 25 °C. Injection was performed for 5 s. The method was validated for the quantification of benzoic acid, salicylic acid and ortho‐aminobenzoic acid in Radix Isatidis, a traditional plant medicine with removal of endotoxin. The separation and determination were satisfactory and quick.  相似文献   

18.
烟酸分子印迹复合膜的制备及其分离性能研究   总被引:1,自引:0,他引:1  
邱增英  钟世安 《化学学报》2010,68(3):246-250
以聚偏氟乙烯微孔滤膜为支撑膜,烟酸为模板分子,用紫外光引发表面修饰聚合制备了微孔滤膜支撑-烟酸分子印迹复合膜.电镜扫描对该印迹复合膜进行了表面形态表征.Scatchard分析表明,在所研究的浓度范围内分子印迹复合膜中存在等价的结合位点,结合位点的平衡离解常数Kd为5.55×10-2mmol·L-1.底物的结合和渗透选择性实验表明,分子印迹复合膜对烟酸有较好的结合性能,结合量是6.10μmol·g-1.与其结构类似的化合物烟酰胺相比,分子印迹复合膜对模板分子展示了更好的选择性及高度的识别能力.  相似文献   

19.
To develop a cost-effective fermentation medium, spent brewer's yeast hydrolysate was evaluated as a nitrogen source for succinic acid production by Actinobacillus succinogenes NJ113 in glucose-containing media. Autolysis and enzymatic hydrolysis were used to hydrolyze the spent brewer's yeast cells to release the nutrients. The results showed that enzymatic hydrolysis was a more effective method due to the higher succinic acid yield and cell growth. However, the incomplete glucose consumption indicated existence of nutrient limitation. Vitamins were subsequently identified as the main limiting factors for succinic acid production using enzymatically hydrolyzed spent brewer's yeast as a nitrogen source. After the addition of vitamins, cell growth and succinic acid concentration both improved. As a result, 15 g/L yeast extract could be successfully replaced with the enzymatic hydrolysate of spent brewer's yeast with vitamins supplementation, resulting in a production of 46.8 g/L succinic acid from 68 g/L glucose.  相似文献   

20.
IntroductionThemethodofseparatingaracemicmixtureintoitsenantiomersthroughtheformationofdiastereomericmolecularcomplexbyreactionwithanopticallyactivecompoundhasbeenwidelyinvestigated .Fromthepointofviewofcrystallography ,anessentialprerequisiteofthesucc…  相似文献   

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