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《Arabian Journal of Chemistry》2023,16(6):104718
Identification and determination of chiral pharmaceutical residues is still a challenging analytical puzzle. In this work, a simple, rapid, and effective method for chiral D/L-tetraiodothyronine (T4) separation and quantitative was developed based on host–guest recognition using ion mobility spectrometry-mass spectrometry (IMS-MS). The D/L-T4 enantiomers were mobility separated by their diastereomeric complexes through mixing with cyclodextrin (CD) and metal ions. D/L-T4 was first separated by complexing with host molecule (α-, β-, γ-CD), observing weak peak-to-peak resolution (Rp-p) by the formed binary complex [CD + D/L-T4-H]+, and the Rp-p decreased with the CD size increasing. However, the separation effect of D/L-T4 was much improved with the addition of divalent metal ions (G2+) by the formed ternary complex [CD + D/L-T4 + G]2+. In comparison, α-CD related complexes can possess the best separation effect for D/L-T4 in most cases. Considering the high selectivity, non-toxic, and chemically stable of β-CD, [β-CD + D/L-T4 + Ca]2+ was selected for D/L-T4 analysis (RP-P = 0.764). Whereafter, chemical theoretical conformations for [β-CD + D/L-T4 + H]+ and [β-CD + D/L-T4 + Ca]2+ were optimized, discovering similar micro-interaction modes between [β-CD + D-T4 + H]+ and [β-CD + L-T4 + H]+; while with the addition of Ca2+, significantly different interaction modes were observed between [β-CD + D-T4 + Ca]2+ and [β-CD + L-T4 + Ca]2+. And theoretical collision cross section (CCS) trends for the complexes were consistent with that of the experimental results. Additionally, calibration curves were linear within 1.00 to 104 ng mL?1 with coefficient (R2 > 0.99), gaining the limit of detection (LODs) calculation of 0.11 ng mL?1, and the detection range between D-T4 and L-T4 of 45.6:1 to 1:59.8. Finally, the method was applied for D/L-T4 detection in Levothyroxine tablets, the detection content has good consistency on drug labeling. Because the proposed method exhibited good analytical performance in terms of speed, selectivity, sensitivity, and reproducibility of the measurements, that can be a promising strategy for effective D/L-T4 detection in pharmaceutical industries or other practical samples. 相似文献
23.
盐酸环丙沙星及其制剂含量测定方法的探讨 总被引:1,自引:0,他引:1
非水滴定法测定盐酸环丙沙星的含量时,需要预先加入冰乙酸和乙酸汞进行转化处理,两种试剂的加入顺序对盐酸环丙沙星的溶解速度影响较大,先加入乙酸汞时,盐酸环丙沙星溶解较快。用高效液相色谱法测定盐酸环丙沙星片及盐酸环丙沙星胶囊的含量时,如果以水作溶剂,测定值明显偏低,宜改用0.l mol/L盐酸溶液作溶剂。 相似文献
24.
毛细管区带电泳法测定复方甘草片中的甘草酸、甘草次酸、吗啡和苯甲酸钠 总被引:9,自引:0,他引:9
在紫外检测波长为 2 2 8nm、电压为 14kV、背景电解质为 5 0mmol/L硼砂溶液、内标为氢氯噻嗪的条件下 ,用毛细管区带电泳法对复方甘草片中的甘草酸、甘草次酸、吗啡和苯甲酸钠进行了定量分析。结果甘草酸、甘草次酸、吗啡和苯甲酸钠的相对峰面积 (组分与内标的峰面积之比 )与各自的质量浓度之间呈良好的线性关系 ,上述 4种组分的平均回收率分别为 98 2 % ,97 3% ,97 1%和 97 5 %。方法简便、快速、准确。 相似文献
25.
Jingwei Li Min Zhao Xue Jiang Tingting Liu Miao Wang Chunjie Zhao 《Biomedical chromatography : BMC》2020,34(4):e4741
Duzhong Jiangya Tablet (DJT) composed of Eucommia ulmoides Oliv. and several other traditional Chinese medicines is a Chinese herbal compound, which is clinically used to treat hypertension. The aim of this study was to evaluate the antihypertensive effect of DJT and amlodipine besylate (AB) on the synergistic treatment of spontaneously hypertensive rats (SHRs), and to explore its antihypertensive mechanism. The synergistic therapeutic effect of DJT in combination with AB on SHR was studied using two metabolomics methods based on mass spectrum (MS) and nuclear magnetic resonance. Metabolomics analysis of plasma, urine, liver, and kidney and the combination of orthogonal partial least squares discriminant analysis was performed to expose potential biomarkers. Then, the overall metabolic characteristics and related abnormal metabolic pathways in hypertensive rats were constructed. Blood pressure measurements showed that DJT combined with AB has better effects in treating hypertension than it being alone. A total of 30 biomarkers were identified, indicating that hypertension disrupted the balance of multiple metabolic pathways in the body, and that combined administration restored metabolite levels better than their administration alone. The changes of biomarkers revealed the synergistic therapeutic mechanism of DJT combined with AB, which provided a reference for the combination of Chinese and Western medicines. 相似文献
26.
建立以核磁共振技术测定片剂中西咪替丁含量的方法。采用Agilent DD2-500型核磁共振波谱仪,以氘代甲醇为溶剂、对苯二甲酸二甲酯为内标,测试温度25℃,弛豫时间为20 s,脉冲角为45°,采集时间为2 s,扫描次数为16次,采集核磁共振氢谱。该方法线性范围为0.1~5.0 mg/mL,相关系数r=0.999 8,测定结果的相对标准偏差为0.11%(n=6),平均加标回收率在100.03%~100.58%之间。用该方法测定不同厂家片剂中西咪替丁的含量,测定结果与药典方法相吻合。该方法简单快速、样品用量少,适用于西咪替丁的质量控制。 相似文献
27.
高效液相色谱法测定磷酸苯丙哌林片的含量 总被引:4,自引:0,他引:4
采用反相高效液相色谱法 ,以醋酸可的松为内标 ,测定磷酸苯丙哌林片的含量。色谱柱为ODS柱 ,以甲醇 水 冰醋酸 三乙胺溶液 (体积比为 6 0∶35∶5∶0 1)为流动相 ,检测波长为 2 70nm ,磷酸苯丙哌林在 9 96mg/L~ 49 8mg/L范围内有很好的线性关系 (r=0 9998) ,平均回收率为 99 91% (n =5 ) ,RSD =0 43%。 相似文献
28.
This paper presents a new application of three-way parallel factor analysis (3W-PARAFAC) model to the coeluting spectrochromatograms for the quantitative resolution of a quaternary mixture system consisting of paracetamol, propyphenazone, and caffeine with aspirin as an internal standard. Spectrochromatograms of calibration standards, validation sets, and unknown samples were recorded as a function of retention time and wavelength in the range of 0.0–2.5?min and 200–400?nm, respectively, using ultra-performance liquid chromatography with photodiode array detection (UPLC-PDA). Three-way UPLC-PDA data array X (retention time?×?wavelength?×?sample) was obtained from the data matrices of the spectrochromatograms. 3W-PARAFAC decomposition of three-way UPLC-PDA data array provided three loading matrices corresponding to chromatographic mode, spectral mode, and relative concentration mode. Quantitative estimation of paracetamol, propyphenazone, and caffeine in analyzed samples was accomplished using the relative concentration mode obtained by the deconvolution of the UPLC-PDA data set. The validity and ability of 3W-PARAFAC model were checked by analyzing independent test samples. It was observed from analyses that 3W-PARAFAC method has potential to uniquely resolve strongly overlapping peaks of analyzed compounds in a spectrochromatogram, which was obtained under experimental conditions consisting of the lower flow rate, short run time, and simple mobile phase composition. The proposed three-way chemometric approach was successfully applied to the simultaneous quantification of paracetamol, propyphenazone, and caffeine in tablets. Experiments showed that the determination results were in good agreement with label amount in commercial pharmaceutical preparation. 相似文献
29.
ICA方法与NIR技术用于药片中活性成分含量的测定 总被引:1,自引:0,他引:1
用独立分量分析(ICA)方法提取药片近红外光谱数据矩阵的独立成分和相应的混合矩阵, 再用BP神经网络对混合矩阵和药片中活性成分的浓度矩阵进行建模, 提出了新的药片活性成分含量测定的基于独立分量分析-神经网络回归(ICA-NNR)的近红外光谱分析方法. 通过分析独立分量数和网络中间隐层的神经元数对模型性能的影响, 分别建立三类药片定量分析的最优模型. 该方法用于实测的三类药片中活性成分含量的测定, 测试样品集的化学检测值与近红外预测值的相关系数分别达到0.962, 0.980及0.979. 结果表明, 基于ICA-NNR的近红外光谱分析方法对制药业的药片进行定量分析是可行的. 相似文献
30.
为提高铌铁合金检验效率,替代繁琐的化学湿法分析,采用粉末压片制样,利用X荧光光谱法对铌铁合金中Fe、Nb、Si、Al、P 5种主要成分进行测定。选用定值过的生产样品作为内控标准样品,主要研究制样细节对分析结果的影响,确认合适的试样粒度和压片参数,通过曲线拟合建立校准曲线。测定结果与化学湿法和电感耦合等离子体原子发射光谱法测定结果比较,各组分精密度相对标准偏差为0.48%~1.9%,准确度满足国标分析要求。 相似文献