基于蛋白质直接电子转移的全胆固醇传感器

以壳聚糖为载体, 将血红蛋白、胆固醇氧化酶及胆固醇酯酶固定在玻碳电极表面, 在不使用任何电子媒介体的条件下, 利用血红蛋白和电极之间的直接电子转移, 制备出高选择性的全胆固醇生物传感器, 并用于测定血清中总胆固醇含量. 利用循环伏安法和恒电位法研究了该传感器的电化学特性. 在优化的实验条件下, 该传感器对胆固醇响应的线性范围为10~110 mg/dL, 检出限为5 mg/dL(信噪比的3倍), 响应时间为60 s. 对人血清中总胆固醇的测定表明, RSD小于6.2%, 回收率为95%~106%.     

中国营养平衡米膳治疗肾衰病人的Ca、P、K、Na、Mg平衡论证

用营养调查方法 ,对门诊 30例血透肾衰患者进行了调查 ,并对其进食中国营养平衡米(下称营养平衡米 )膳中Ca、P、K、Na、Mg进行了论证。临床表现为面黄肌瘦、苍白、浮肿、疲劳、消瘦、虚弱、无力、食欲不振、恶心呕吐、头晕、皮肤瘙痒、肌肉震颤、手足麻木、无精神等明显的营养不良表现 ,平均体重 5 3 5kg ,皮脂厚度 1 1 2cm ,血清总蛋白 6 7 31mg/dL ,白蛋白 37 4 9mg/dL ,RBC 2 4 1× 1 0 12 /L ,HGB 6 8 81g/L ,PLT 1 72 1× 1 0 9/L ,K 1 6 1 5mg/dL ,Na392 72mg/dL ,C1 2 88 2 2mg/dL ,Ca 6 2 8mg/dL ,P 6 1 1mg/dL ;氮质血症 (x) :BUN 31mmol/L ,Cr 1 0 0 2 6 μmol/L ;膳食中平均每人每日常量元素摄入量为Ca34 1 4 3mg、P 70 7 0 9mg、K1 2 1 5 5 6mg、Na 2 2 2 6 1 9mg、Mg 1 79 4 5mg ,以肾衰病人RDA标准为Ca 1 0 0 0 /1 5 0 0 ,P 6 0 0 ,K5 0 0 ,Na 1 0 0 0 ,Mg 2 0 0 /30 0 ,评价分别为 2 3%～ 34 %、 1 1 8%、 2 4 3%、 2 2 3%、 6 0 %～ 90 % ,则K、Na、P过量 ,而Ca、Mg不足。若改食用营养平衡米膳 ,摄入量分别为 1 4 2 3、 92 4、 1 4 32、 2 2 36、2 79mg ,达标率分别为 95 %～ 1 4 2 % ,1 5 4 % ,2 86 % ,2 2 4 % ,93%～ 1 4 9%。则达标率 1 0 0 % ,且比原来膳食中元素平衡。     

人血清中总蛋白的四羧基铁酞菁二级散射法测定

在pH3.8的Britton-Robinson (B-R)缓冲溶液中,蛋白质与四羧基铁(Ⅲ)酞菁(Fe(Ⅲ)Pc (COOH)4)结合,使二级散射信号ISOS增强,且增强的二级散射信号与蛋白质浓度呈良好的线性关系.在最大的二级散射波长(λSOSmax)处分别对牛血清白蛋白(BSA)、人血清白蛋白(HSA)、人免疫球蛋白(IgG)、α-糜蛋白酶(α-Chy)进行测定,线性范围分别为0.0～1.80mg/L、0.0～1.60 mg/L、0.03～1.20mg/L、0.0～1.20mg/L;相应检出限分别为0.501、0.354、3.63、1.18μg/L.将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法基本一致.     

耐尔蓝-十二烷基苯磺酸钠-蛋白质体系的荧光反应及其分析应用

研究了耐尔蓝-十二烷基苯磺酸钠体系的吸收光谱和荧光光谱特性，并以此体系建立了测定蛋白质的新型荧光探针。在优化实验条件下，对人血清白蛋白和γ-球蛋白测定的线性范围均为0．16mg/L，检出限分别为0．020mg/L和0．036mg/L。该方法用于人血清中总蛋白含量的测定，与临床测定结果相吻合。     

蛋白质-四羧基铜酞菁体系的共振散射行为及其分析应用

在pH 3.0的Clark-Lub's 缓冲溶液中,蛋白质与四羧基铜酞菁(CuPc(COOH)4)作用,使体系的共振光散射增强,在λ=389 nm处光散射强度最大.增强作用的强弱与蛋白质的含量成正比,据此建立了共振光散射测定蛋白质的新方法.此方法对牛血清白蛋白(BSA)、人血清白蛋白(HSA)、免疫球蛋白G(IgG)、鱼精蛋白(Protamine)、血清总蛋白(TP)的测定范围分别为0.05～1.60 mg/L、 0.025～1.60 mg/L、 0～1.45 mg/L、 0.1～1.50 mg/L、 0～1.60 mg/L,相应检出限分别为1.12×10-2 mg/L、 1.11×10-2 mg/L、 1.95×10-2 mg/L、 3.61×10-3 mg/L、 4.34×10-3 mg/L.方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法基本一致.     

快速测定植物油胆固醇含量在地沟油筛查中的应用

采用皂化气相色谱氢火焰离子检测器法测试了多个植物油样品,发现胆固醇峰被干扰比较严重,很难得出植物油与地沟油胆固醇含量的界定值。采用SPE进行样品前处理,对SPE处理条件进行优化,得出优化条件为称样量0.25 g ,20 mL 0.6%乙醚-正己烷(V/V)作为淋洗液,20 mL 15%乙醚-正己烷(V/V)作为洗脱液。用SPE气相色谱氢火焰离子检测器法分析了84个植物油样品和13个地沟油样品中胆固醇含量,测定结果表明,植物油胆固醇含量与地沟油胆固醇含量有明显区别,所有植物油胆固醇含量都小于50μg/g,13个地沟油样中11个样胆固醇含量大于50μg/g。因此,采用上述植物油胆固醇测定方法,胆固醇含量超过50μg/g可判定为疑似地沟油,反之不成立。本方法在0~760 mg/L浓度范围内相关系数R2=0.9999,方法检出限为6. 0μg/g,两个浓度水平(17.7和695 mg/L)的相对标准偏差分别为1.6%和1.5%,回收率为103%。     

新荧光增敏法测定人血清蛋白质

合成了新荧光试剂5-(4-羧基苯偶氮)-8-水杨醛缩氨基喹啉(p-CPSAQ),探讨了与人血清蛋白反应的最佳实验条件.在pH=7.0的缓冲体系中,蛋白质的存在使p-CPSAQ的荧光大大增强,据此建立了测定人血清蛋白质的灵敏方法;对人血清白蛋白和γ-球蛋白的线性范围分别为0.1～4.5 mg/L和 0.1～4.0 mg/L;检出限分别为0.028和0.027 mg/L.方法灵敏、快速、选择性好,用于人血清样品中总蛋白的测定,结果满意.     

四羧基镍酞菁共振散射法测定蛋白质

建立了一种测定蛋白质的新方法．在pH3．6的Britton-Robinson（B-R）缓冲溶液中,蛋白质与四羧基镍酞菁NiPc（COOH）4发生相互作用,使体系在λ=388nm处的共振散射（RLS）增强,并且增强的散射强度（IRLS）与蛋白质的含量成比例,据此利用四羧基镍酞菁NiPc（COOH）4为光谱探针共振散射法测定人血清中的总蛋白质,同时优化了体系光散射检测的实验参数．在最佳的实验条件下,对牛血清白蛋白（BSA）、人血清白蛋白（HSA）、人血清总蛋白（TP）的线性范围分别为0．00～1．20mg／L、0．00～1．00mg／L、0．00～1．00mg／L,相应检测限分别为5．97×10^-4mg／L、2．90×10^-4mg／L、4．76×10^-4mg／L．将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法比较,令人满意．     

靛蓝胭脂红共振瑞利散射法测定蛋白质

在pH 2.34的B-R缓冲溶液中,靛蓝胭脂红及蛋白质的共振瑞利散射(RRS)均十分微弱。但两者结合时,形成的复合物能使RRS信号急剧增强,最大散射波长为393 nm。测定人血清白蛋白、牛血清白蛋白、γ-人球蛋白、卵白蛋白的线性范围分别为0.1~3.7、0.08~3.0、0.05~2.0、0.1~2.4 mg/L;相应的检出限分别为24.6、20.7、20.4、25.7μg/L。本法用于人血清、牛奶、豆浆、尿液中总蛋白质的测定,结果与经典的考马斯亮蓝法一致。     

毛细管电泳-电化学检测法测定淮山中薯蓣皂苷和腺苷含量

建立了毛细管电泳-电化学检测(CE-ED)法测定淮山中薯蓣皂苷和腺苷的含量。考察了检测电位、运行缓冲液浓度和pH、分离电压及进样时间等的影响。在优化的实验条件下,对0.1mg/L薯蓣皂苷、腺苷在9min内实现了分离,其线性范围分别为0.1~1 000μg/L和0.1~1 200μg/L;检出限分别为0.04μg/L和0.03μg/L,峰电流的相对标准偏差(RSD,n=6)分别为1.7%、1.5%,迁移时间的RSD分别为0.7%、0.6%。该方法已用于淮山样品中薯蓣皂苷和腺苷的测定,样品加标回收率在98.0%~102.5%之间,RSD≤2.3%。     

Rapid determination of Paeoniae Radix using near infrared spectroscopy

A rapid and nondestructive near infrared spectroscopy (NIRS) was used to differentiate different geographical Paeoniae Radix and quantitatively predict the content of main active components. Paeoniflorin, albiflorin and benzoylalbiflorin were analyzed simultaneously with an Agilent Zorbax SB-C₁₈ column by gradient elution under high-performance liquid chromatography-UV detection (HPLC-UV). Multiplicative scatter correction (MSC), first derivative and Savitsky-Golay were utilized together to correct the scattering effect and eliminate the baseline shift in all near infrared diffuse reflectance spectra in order to give a better correlation with the results obtained by HPLC-UV. Multiplicative regression methods were discussed. The spectra calibration equations produced highest correlation coefficient values (R²) and lowest root mean square error of prediction (RMSEP) were used for the determination of paeoniflorin, albiflorin and benzoylalbiflorin. The RMSEP of paeoniflorin, albiflorin and benzoylabiflorin were 0.866 mg/g, 0.369 mg/g and 0.084 mg/g, respectively, and the R² of cross validation were 0.986, 0.939 and 0.971, respectively. Furthermore with the use of principle component analysis (PCA), Paeoniae Radix was clustered according to different cultivation area. The results indicated that the NIRS method could be used for the quality control of Chinese herbal medicine.     

白酒基酒中酮类物质的近红外光谱检测方法

应用近红外光谱技术建立了白酒基酒中2,3-丁二酮和3-羟基-2-丁酮的快速检测模型。从洛阳杜康酒厂选取182个白酒基酒样品为材料,运用气相色谱法测得两种物质的化学值,同时采集其在12 000~4 000 cm-1范围内的光谱数据,采用偏最小二乘法(PLS)结合内部交叉验证建立校正模型。通过对比不同光谱预处理下PLS模型效果对其进行优化,确定2,3-丁二酮和3-羟基-2 丁酮的最佳预处理方法分别为一阶导数+多元散射校正和二阶导数,最佳光谱区间分别为9 403.2~7 497.9 cm-1和9 403.2~7 497.9 cm-1+6 101.7~5 449.8 cm-1。优化后2,3-丁二酮和3 羟基-2-丁酮校正集样品的化学值和近红外预测值的决定系数(R2)分别为0.960 2和0.963 2,交叉验证均方根误差(RMSECV)分别为0.39、0.22 mg/100 mL;通过外部检验,验证集样品的R2分别为0.957 6和0.957 8,预测均方根误差(RMSEP)分别为0.40、0.24 mg/100 mL。结果表明,应用近红外光谱技术结合化学计量学方法所建立的模型有较高的准确度,能够满足白酒生产中酮类物质的快速检测需要。     

应用遗传算法和PLS的近红外光谱预测玉米中淀粉含量的研究

以普通玉米籽粒为试验材料,在应用遗传算法结合偏最小二乘回归法对近红外光谱数据进行特征波长选择的基础上,应用偏最小二乘回归法建立了特征波长测定玉米籽粒中淀粉含量的校正模型．试验结果表明,基于11个特征波长所建立的校正模型,其校正误差（RMSEC）、交叉检验误差（RMSECV）和预测误差（RMSEP）分别为0.30％、0.35％和0.27％,校正数据集和独立的检验数据集的预测值与实际测定值之间的相关系数分别达到0.9279和0.9390,与全光谱数据所建立的预测模型相比,在预测精度上均有所改善,表明应用遗传算法和PLS进行光谱特征选择,能获得更简单和更好的模型,为玉米籽粒中淀粉含量的近红外测定和红外光谱数据的处理提供了新的方法与途径．     

鱼粉近红外光谱模型传递应用研究

为探讨光栅型与傅里叶变换型近红外分析仪之间模型传递的应用效果,选取国产鱼粉为近红外光谱样本,DS2500F型近红外分析仪为源仪器,MPA型近红外分析仪为目标仪器,采用分段直接校正(PDS)方法实现近红外光谱传递。分别建立水分、粗蛋白质、粗脂肪、蛋氨酸和赖氨酸等组分的预测模型,通过交互验证决定系数(R2cv)、交互验证标准误差(RMSECV)、马氏距离(MD)、系统偏差(Bias)、预测均方根误差(RMSEP)和相对分析误差(RPD)等参数,多维度评估光谱传递后所建预测模型的效果。结果表明,DS2500F仪器的近红外光谱传递到MPA型仪器时,所建国产鱼粉的水分、粗蛋白质、粗脂肪、蛋氨酸、赖氨酸的预测模型与MPA型仪器原始预测模型各参数对比无显著差异,预测效果基本一致,说明国产鱼粉在DS2500F仪器上的近红外光谱通过传递可以替代MPA型仪器的原始光谱,间接实现了模型传递,且具有良好的适用性和共享性,可提高近红外预测模型的应用效率。     

Comparison and joint use of near infrared spectroscopy and Fourier transform mid infrared spectroscopy for the determination of wine parameters

A study of the statistic characteristics of the multidetermination of several enological parameters - namely, alcoholic degree, volumic mass, total acidity, glycerol, total polyphenol index, lactic acid and total sulphur dioxide - depending on the spectroscopic zone employed, was carried out. The two techniques used were near infrared spectroscopy (NIRS) and Fourier transform mid infrared spectroscopy (FT-MIRS). The combination of these two regions (sum of their spectra) was also studied. NIRS yielded better results, but the use of both zones improved the determination of glycerol and total sulphur dioxide. The training and validation sets used for developing general equations were built with samples from different apellation d’origine, different wine types, etc. Partial least squares regression was used for multivariate calibration, using systematic cross validation in the calibration stage and external validation in the testing stage. Sample preparation was not required.     

偏最小二乘近红外光谱法测定瘦肉脂肪酸组成的研究

利用偏最小二乘将瘦肉的近红外光谱数据分别与其棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸含量建立校正模型,并用交互校验和外部检验来考查模型的可靠性.各脂肪酸模型的校正相关系数分别为0.9998、0.9844、0.9963、0.9754、0.9969,均方估计残差(RMSEC)分别为0.0231、0.0485、0.111、0.373、0.311,交互校验均方残差(RMSECV)分别为0.509、0.115、0.225、0.848、0.649.应用所建立的各脂肪酸近红外模型对瘦肉脂肪酸组成进行预测,并对各脂肪酸的预测值与气相色谱法测定值进行配对t-检验,结果表明两者差异均不显著(p>0.05).     

Ex-vivo determination of blood glucose by microdialysis in combination with infrared attenuated total reflection spectroscopy

Several biosensors have been developed for continuous monitoring of human blood glucose, which is desirable for insulin-dependent diabetic patients. Developments in the field of quantitative assays using infrared attenuated total reflection spectroscopy allow the determination of metabolites at low concentrations. The microdialysis technique can provide a continuous sampling of extracellular body fluids. As only compounds of low molecular weight are passed on, infrared spectrometric quantitation is eased considerably. Samples were obtained by microdialysis of human blood plasma and aqueous glucose solutions. Multivariate calibration by partial least-squares was evaluated for its analytical performance in ex-vivo blood glucose monitoring. Mean squared prediction errors obtained by cross validation were 5.4 mg/dL for dialysate samples from different patients and 1.3 mg/ dL for dialysates from glucose solutions. Further investigations were carried out to achieve miniaturization of the measuring and detection device. Received: 5 December 1996 / Revised: 20 March 1997 / Accepted: 29 March 1997     

Ex-vivo determination of blood glucose by microdialysis in combination with infrared attenuated total reflection spectroscopy

Several biosensors have been developed for continuous monitoring of human blood glucose, which is desirable for insulin-dependent diabetic patients. Developments in the field of quantitative assays using infrared attenuated total reflection spectroscopy allow the determination of metabolites at low concentrations. The microdialysis technique can provide a continuous sampling of extracellular body fluids. As only compounds of low molecular weight are passed on, infrared spectrometric quantitation is eased considerably. Samples were obtained by microdialysis of human blood plasma and aqueous glucose solutions. Multivariate calibration by partial least-squares was evaluated for its analytical performance in ex-vivo blood glucose monitoring. Mean squared prediction errors obtained by cross validation were 5.4 mg/dL for dialysate samples from different patients and 1.3 mg/ dL for dialysates from glucose solutions. Further investigations were carried out to achieve miniaturization of the measuring and detection device.     

近红外光谱技术定量分析连作滁菊土壤中的阿魏酸含量

应用近红外光谱(NIRS)技术定量分析连作滁菊土壤样品中阿魏酸的含量.通过标准杠杆值、学生残差和马氏距离判断异常光谱,经二阶导数和Norris平滑滤噪预处理后,在6000~4000 cm-1范围,最佳因子数为7,采用偏最小二乘法(PLS)构建数学模型.结果表明,模型校正集和验证集与高效液相色谱仪(HPLC)测定的参考值之间均呈现良好相关关系,校正相关系数Rc为0.9914,交叉验证相关系数Rcv为0.9935,校正集误差均方根(RMSEC)为0.484,预测误差均方根(RMSEP)为0.539,交叉验证误差均方根(RMSECV)为0.615.研究结果表明,NIRS分析技术能够实现连作土壤中阿魏酸的快速检测,结果准确可靠.     

Measurement of lactate in whole human blood with near-infrared transmission spectroscopy

We have evaluated the potential of near-infrared spectroscopy (NIRS) as a technique for rapid analysis of lactate in whole blood. To test the NIRS technique, a comparison was made with a standard clinical method using whole blood samples taken from five exercising human subjects at three different stage of exercise. To expand lactate concentration within the physiological range, standard additions method was used to generate 45 unique data points. Spectra were collected over the 2050-2400 nm spectral range with a 1 mm optical path length quartz cell. Reference lactate concentrations in the samples were determined by enzymatic measurements. Estimates and calibration of the lactate concentration with NIRS was made using partial least squares (PLS) regression analysis and leave-N-out cross validation on second derivative spectra. Separate calibrations were determined from each of the subject samples and cumulative PRESS was used to determine the number of PLS factors in the final model. The results from the PLS model presented are generated from the five individual calibration coefficient vectors and provided a correlation coefficient of 0.978 and a standard error of cross validation of 0.65 mmol l⁻¹ between the enzymatic assay and the NIRS technique. To study the parameters that impact the spectra baseline and the correlation between the calculated model and the data, referenced measurements of lactate against baseline spectrum were made for each individual. A correlation coefficient of 0.992 and a standard error of cross validation of 0.21 mmol l⁻¹ were found. The results suggest that NIRS may provide a valuable tool to assess physiological status for both research and clinical needs.