Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively...Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.展开更多
以红枣发酵饮料为研究对象,利用顶空固相微萃取和气相色谱-嗅闻-质谱联用法分析其易挥发性成分并对其进行了分析,对影响固相微萃取操作条件的萃取头、萃取温度、萃取时间、样品用量、平衡时间和解吸时间进行系统的优化,旨在建立一种分...以红枣发酵饮料为研究对象,利用顶空固相微萃取和气相色谱-嗅闻-质谱联用法分析其易挥发性成分并对其进行了分析,对影响固相微萃取操作条件的萃取头、萃取温度、萃取时间、样品用量、平衡时间和解吸时间进行系统的优化,旨在建立一种分析红枣发酵饮料易挥发性成分的方法,并通过嗅闻检测结合气味活度值和香气强度值确定红枣发酵饮料的特征风味成分,采用草酸二乙酯做内标对特征风味成分进行了含量测定。结果表明:选用50/30μm DVB/CAR/PDMS固相微萃取头、Rtx-WAX色谱柱、样品用量8.0 m L/20.0 m L样品瓶、加盐量3.00 g、萃取时间70 min、萃取温度70℃、平衡时间20 min、解吸时间3 min,分析红枣发酵饮料易挥发性成分,共检出114种组分,确定结构96种,占总易挥发性成分总量的98.86%;气味活度值及香气强度值分析结果表明:乙酸乙酯、戊酸乙酯、己酸乙酯、2-辛酮、2-十一酮、乙酸-2-苯乙酯、苯丙酸乙酯、6-甲基-5-庚烯-2-酮、苯甲醛和3-羟基-2-丁酮为红枣发酵饮料的特征风味成分。展开更多
[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extr...[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry （GC/MS）. [Result] The results show that cedrol （46.39%） is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate （59.46%） is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value.展开更多
文摘Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.
文摘以红枣发酵饮料为研究对象,利用顶空固相微萃取和气相色谱-嗅闻-质谱联用法分析其易挥发性成分并对其进行了分析,对影响固相微萃取操作条件的萃取头、萃取温度、萃取时间、样品用量、平衡时间和解吸时间进行系统的优化,旨在建立一种分析红枣发酵饮料易挥发性成分的方法,并通过嗅闻检测结合气味活度值和香气强度值确定红枣发酵饮料的特征风味成分,采用草酸二乙酯做内标对特征风味成分进行了含量测定。结果表明:选用50/30μm DVB/CAR/PDMS固相微萃取头、Rtx-WAX色谱柱、样品用量8.0 m L/20.0 m L样品瓶、加盐量3.00 g、萃取时间70 min、萃取温度70℃、平衡时间20 min、解吸时间3 min,分析红枣发酵饮料易挥发性成分,共检出114种组分,确定结构96种,占总易挥发性成分总量的98.86%;气味活度值及香气强度值分析结果表明:乙酸乙酯、戊酸乙酯、己酸乙酯、2-辛酮、2-十一酮、乙酸-2-苯乙酯、苯丙酸乙酯、6-甲基-5-庚烯-2-酮、苯甲醛和3-羟基-2-丁酮为红枣发酵饮料的特征风味成分。
基金Supported by Sub-project of the "Eleventh Five-Year" National Science and Technology Support Program (2006BAD19B04)~~
文摘[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry （GC/MS）. [Result] The results show that cedrol （46.39%） is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate （59.46%） is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value.
