Identification of Colorants in Food by Surface-enhanced Raman Spectroscopy and Wavelet-based Reverse Search

使用金纳米粒子为增强因子的表面增强拉曼光谱技术,通过连续小波变换将拉曼光谱信号转化到小波空间(墨西哥帽小波作为小波基)。该步骤能够减轻信号中基线; 变化及随机噪音的影响并找到峰位置和最佳小波尺度系数。依据小波空间中的信息,对混合物光谱及标准谱光谱进行反向搜索得到反向搜索匹配系数(Revere; match quality,; RMQ),作为判断混合物中目标成分是否存在的依据。该算法可对混合物中的目标物质进行准确定性,并已成功应用于多种食品中色素鉴定。食品中色素的检出率; 达到99%,且结果稳健,其效果明显优于传统的命中质量系数法(Hit quality index,; HQI)。这证实了小波空间反向搜索方法是一种快速而准确的拉曼光谱定性算法。In this study, a gold nanocrystal colloid was used as the enhancement; factor for surfaceenhanced Raman scattering (SERS). Raman spectra were; transformed by continuous wavelet transform (CWT),and Mexican hat; wavelet were chosen as the wavelet basis. This procedure could be used; to alleviate the influence of baseline variations and random noise,and; find peak positions and the best scale wavelet coefficients of signal.; Reverse search method was proposed to compare the spectrum of an unknown; sample with a spectrum of standard using the information in wavelet; space. Reverse match quality (RMQ) could be obtained automatically to; determine whether a substance is present. It was used to identify; colorants in a variety of food successfully. The colorants could be; identified with 99 percent accuracy. It shows a better performance; compared with traditional hit quality index (HQI). The study confirmed; that the wavelet-based reverse search is feasible and accurate in; qualitative analysis.国家自然科学基金资助项目; 国家重大科学仪器设备开发专

Developing On-site,Quick Screening Platform for Artificial Pigments in Food Using Surface-enhanced Raman Spectroscopy

已有研究表明食品加工过程中添加的人工合成色素不仅不能提供营养物质,而且可能是导致小儿多动症的来源之一,影响儿童智力发育.基于表面增强拉曼光谱(SERS)原理和便携式拉曼光谱仪,提出了一种非定向的现场快速筛查方法.该方法只需对疑似含有人工合成色素的固体或液体状食品样品进行简单前处理,即可进行SERS检测.样品前处理和检测的总时长不超过15 min,检出质量浓度在1 mg/L水平,可有效满足政府职能部门的现场执法需求.除具有快速、方便、灵敏度高等特点之外,该检测方法的最大优势在于实现了未知样品的现场非定向测试:在同一种前处理过程和检测方法下,可对食品中常添加的亮蓝、胭脂红、日落黄、柠檬黄、苋菜红和诱惑红6种人工合成色素进行快速鉴定和半定量分析.As widely used additives in food processing,artificial pigments have no any nutrition but are potential sources of hyper-activity and affect the intellectual development of children.On the basis of surface-enhanced Raman spectroscopy( SERS) and portable Raman instrument,we developed a non-targeting,on-site and quick screening platform for artificial pigments in food matrix. SERS measurement could be carried out after the food matrix( either in solid or liquid states) being simply pretreated for 15 min.The detectable concentration is as low as 1 mg / L,a level meeting the demand of the on-site enforcement by the government.Besides the advantages of quick,easy-on-going,and high sensitivity,the most distinguished point of SERS is the non-targeting qualitative on-site detection for the typical pigment additives,including brilliant blue,carmine,sunset yellow,lemon yellow,amaranth and allura red,et al.,while both the pretreatment procedure and the SERS detection remain the same.国家自然科学基金(21473140);; 福建省高校产学合作项目(2016Y4012);; 中央高校基本科研业务费专项(2072016011

Correlation analysis between bone metabolism and blood stasis in perimenopausal women

目的探讨围绝经期女性骨代谢状况与"血瘀"的关联性。方法 132例符合纳入标准的围绝经期女性按年龄每5岁为一组,分为4组,采用电化学发光法检测不同阶段Ⅰ型胶原氨基端前肽(PINP)、Ⅰ型胶原羧基端肽β特殊序列(β-CTX)、骨钙素N-端中分子片段(N-MID)等骨代谢指标,同时检测血液流变学指标,并对其进行"血瘀"量化评分、甲襞微循环评分,相关数据采用多元回归等统计学进行分析。结果 PINP与全血中切粘度、血瘀量化评分、甲襞微循环评分存在显著的正相关(P<0.01);β-CTX与血瘀量化评分、甲襞微循环评分存在显著的正相关(P<0.01),与红细胞电泳时间存在显著负相关(P<0.01),与全血低切粘度、红细胞刚性指数存在正相关(P<0.05);N-MID与全血中切粘度、血瘀量化评分、甲襞微循环评分存在显著正相关(P<0.01)与全血低切粘度存在正相关(P<0.05)。结论围绝经女性骨代谢状况与"血瘀"关系密切,血瘀是导致围绝经女性骨代谢状况发生变化而发生骨质疏松的重要因素之一。Objective To discuss the correlation between bone metabolism and blood stasis in perimenopausal women. Me thods132 cases of perimenopausal women meeting the inclusion criteria were divided into 4 groups by every 5-year age. Type I collagen amino-terminal propeptide( PINP),carboxy-terminal peptide β special sequence( β-CTX),and molecular osteocalcin N- terminal fragment( N-MID) were detected with electrochemical luminescence at different stages. Blood rheology,blood stasis quantitative score,and microcirculation score were simultaneously detected. Data were analyzed using multiple regression method. Re sults PINP was positively correlated with shear viscosity of whole blood,blood stasis quantitative score,and microcirculation score( P <0. 01). β-CTX was positively correlated with blood stasis quantitative score,microcirculation score,lowshear whole blood viscosity,and erythrocyte rigidity index( P < 0. 01),but was negatively correlated with erythrocyte electrophoresis time( P <0. 01). N-MID was positively correlated with whole blood viscosity,blood stasis quantitative score,microcirculation score( P <0. 01),and lowshear whole blood viscosity( P < 0. 05). Conclusion Bone metabolism and blood stasis are closely related in perimenopausal women. Blood stasis is one of the important factors leading to osteoporosis and change of bone metabolism in perimenopausal women.福建省医学创新课题(2012-CXB-26);; 福建省中医药课题(WST201205

Developing fast laboratory screening platform for sulfate dioxide in food by surface-enhanced Raman spectroscopy

基于表面增强拉曼光谱(SERS)的指纹图谱的高能量分辨率,以位于~630; cm~(-1)亚硫酸根的特征峰为定性和定量依据,本文开展了食品中滥用和非法添加二氧化硫的直接检测研究:一种检测流程实现了不同食品基质中二氧化硫的; 高灵敏检测,最低检出浓度达1 mg; kg~(-1)的水平.针对实际样本的传统蒸馏法前处理流程的一些不足以及SERS检测的指纹图谱优势,本文进行了三方面显著改进:; (1)碳酸钙和沸石取代氮气以提高二氧化硫的挥发提取效率; (2)草酸取代盐酸酸化蒸馏溶液,以有效避免挥发性强酸对操作环境的危害;; (3)氢氧化钠溶液代替乙酸铅溶液作为吸收液,以防止二次污染.环境友好、灵敏度高和不受基质干扰等特点使得本方法有望取代经典蒸馏法和比色法,用于食品; 中非法添加二氧化硫类添加剂的快速高效筛查.The direct detection of sulphur dioxide has been realized in various; food matrixes with high sensitivity and high selectivity, on the basis; of the integration of the high energy resolution of the finger-print; spectrum of surface-enhanced Raman spectroscopy and the universal but; easy-on-going pretreatment procedure. The characteristic peak of sulphur; dioxide at ~630 cm~(-1) was applied as the qualitative and quantitative; standard, which displayed a lowest detectable concentration at the 1 mg; kg~(-1) level for the spiked food samples. The key point of the high; sensitivity and selectivity is the effective pretreatment born out of; the standard distillation one, which has been improved in the three; parts. (1) Using CaCO_3 and Zeolite instead of N_2 gas as the bubbling; reagent. (2) Using oxalic acid as the acidic distillation solution to; eliminate the hazards from acid volatilization, such as hydrochloric; acid. (3) Using diluted sodium hydroxide solution as the absorption; reagent instead of lead acetate solution to avoid the secondary; pollution. With the three distinguished advantages of environment; friendly, high sensitivity and free of matrix interference, the proposed; method has great potential to replace the traditional ones for the fast; screening of the illegal or abused sulphur dioxide in food.国家自然科学基金; 福建省高校产学合作项目; 中央高校基本科研业务费专项资

西峰蔡家咀黄土剖面记录的末次盛冰期到全新世最佳期气候变化

采用挖探井方式获取西峰蔡家咀剖面200 cm黄土沉积序列,以7个14C-AMS测年数据为年龄控制点,利用沉积物粒度模式建立最近20 ka的年代框架。磁化率、灰度、粒度等指标的综合对比表明该剖面记录了末次盛冰期增温以来几次重要气候事件,如Heinrich事件1(H1)、Blling-Allerd暖期(B-A)、新仙女木事件(YD)、8.2 ka事件等,说明西峰黄土剖面具有记录短尺度气候突变事件的潜力

Study on Protein Expression and Physiological Differences Among Four Morphologic Filaments of Spirulina platensis

无论是在生产还是在实验室培养条件下,螺旋藻多形性变异现象普遍存在.本研究从钝顶螺旋藻(SPIrulInA PlATEnSIS)中分离纯化获得了4种不同形态的藻丝体,分别是直线形藻丝体(SPl)、低度螺旋形藻丝体(SPS-l)、中度螺旋形藻丝体(SPS-M)和高度螺旋形藻丝体(SPS-H).对这4种不同形态螺旋藻的生长速率、光合作用、叶绿素A(CHl A)含量分别进行研究,发现这4种不同形态藻丝体在生长和光合生理上存在明显的差异.而总蛋白的SdS-PAgE分析也表明,不同形态藻丝体在蛋白的表达上也有差异,其中34 ku的蛋白只在直线形藻丝体SPl中大量表达.Polymorphic variation of Spirulina has frequently been observed under laboratory and industrial condition.In our laboratory conditions,four morphological filaments of Spirulina platensis,which were linear filament(spL),loose spiraled filament(sps-L),regularly spiraled filament(sps-M) and tightly spiraled filament(sps-H),were respectively separated and axenically cultivated.Further research showed that there are significant differences in growth rate,photosynthesis,and content of chlorophyll a among four forms of filaments.Furthermore,SDS-PAGE analysis also showed some obvious differences in total proteins extracted respectively from four forms of Spirulina platensis.The 34 ku protein,which was highly expressed in the linear filaments,was almost absent from the helical filaments.国家自然科学基金(30571446)资

Preparation of nanocellulose from sugarcane bagasse

Cellulose is extracted from sugarcane bagasse by alkaline peroxide pretreatment. The resulting cellulose is hydrolyzed in 6 mol/L sulfuric acid. The samples are characterized by XRD, SEM, FT-1R and TG. The effect of hydrolysis time and the times of pretr

基于傅里叶级数的踝关节运动模型研究

对人体下肢运动模型的研究是外骨骼机器人驱动和控制系统的核心内容之一,针对利用分段函数拟合踝关节运动模型时存在拟合过程复杂、模型高阶求导之后不连续等缺点,采用傅里叶级数拟合法建立踝关节在矢状面内平地行走运动模型,通过该方法获得的踝关节运动模型具有简洁、准确、无冲击等特点,而且该运动模型还具有高阶连续性和可导性。最后,通过实验验证该模型可以描述健康人体平地常速行走时踝关节运动特征;同时通过ADAMAS进行运动仿真,验证其用于外骨骼机器人的踝关节驱动的正确性。该运动模型研究为研究健康人体正常行走时踝关节运动特征提供了重要的理论依据,并为外骨骼机器人踝关节的驱动和控制提供了参考模型