Classification of Guizhou Aspidistra Plants by Near-infrared Diffuse Reflectance Spectroscopy

[Objective] This study was conducted to establish a near-infrared diffuse reflectance spectroscopy of Guizhou Aspidistra plants. [Method] Twenty three batch- es of Guizhou Aspidistra plants including A. chishuiensis, A. spinula, A. Caespitosa, A. sichuanensis, A. ebianensis, A. retusa, A. guizhouensis and A. liboensis were subjected to drying, pulverization and sieving and then directly determined for near- infrared reflectance spectrums; and the plants in this genus were classified by clus- ter analysis and principal component analysis （PCA）. [Result] The near-infrared re- flectance spectrums of the 23 batches of Guizhou Aspidistra plants showed very high similarity. The spectrums were processed by first derivative method, and the spectral range of 4 000-7 500 cm-1 was selected as the analytical range. Cluster analysis and PCA were employed to mass spectrum variables of plants in Aspidis- tra, fewer new variables became the linear combination of primary variables, and small differences between different varieties were enlarged, thereby facilitating intu- itive classification of plants in this genus. [Conclusion] Near-infrared diffuse re- flectance spectroscopy is nondestructive and rapid for determination of solid sam- pies, and provides a new method for the classification of Guizhou Aspidistra plants combined by information processing techniques.

Rapid Identification for Drought Resistance of Wheat Using Near-infrared Diffuse Reflectance Spectroscopy

[Objective] This study aimed to establish an identification system for drought-resistance in wheat by using near-infrared diffuse reflectance spectroscopy. [Method] In 2006-2007, 36 wheat varieties with different drought resistance were selected and were classified according to their drought resistance grades determined by the Technical Specification of Identification and Evaluation for Drought Resistance in Wheat （GB/T 21127-2007）. In addition, the harvested wheat seed samples were spectrally analyzed with FOSS NIRSystems5000 near-infrared spectrum analyzer for grain quality （full spectrum analyzer） and then the forecasted regression equations were established. [Result] After the establishment of a database and validation, dis- criminated functions were obtained. The determination coefficient （RSQ） and coeffi- cients of determination for cross validation （1-VR） in the discriminant function built with seed samples from water stress area were 0.846 0 and 0.781 8, respectively, which indicated that the consistency between drought resistance and spectral charac- teristics in wheat varieties was good, and there was high correlation between the near-infrared diffuse reflectance spectra of seeds and the drought resistance in wheat. [Conclusiou] Under water stress condition, it is feasible to establish a conve- nient, rapid and no-damage identification system for the drought resistance in wheat by using the near-infrared diffuse reflectance spectrum technique to scan wheat seeds.

Rapid, Non-Destructive, Textile Classification Using SIMCA on Diffuse Near-Infrared Reflectance Spectra

Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the time at the 95% confidence level (p = 0.05 significance level). In the present study, cotton and silk had a 62% and 24% chance, respectively, of being classified with their own group and also with rayon. SIMCA correctly identified a counterfeit “silk” sample as polyester. When coupled with diffuse NIR reflectance spectroscopy and a large sample library, SIMCA shows considerable promise as a quick, non-destructive, multivariate method for fiber identification. A major advantage is simplicity. No sample pretreatment of any kind was required, and no adjust-ments were made for fiber origin, manufacturing process residues, topical finishes, weave pattern, or dye content. Increasing the sample library should make the models more robust and improve identification rates over those reported in this paper.

RAPID DETERMINATION OF PROTEIN IN MILLET BY FOURIER TRANSFORM NEAR-INFRARED(FTNIR)DIFFUSE REFLECTANCE SPECTROSCOPY

In this paper,the Fourier transform near-infrared(FTNIR)diffuse reflectance spectroscopy is applied for the rapid determination of protein in millet.The partial least-squares(PLS)regression is successfully used as an effective multivariate calibration technique.The calibration set is composed of 20 standard millet samples that the protein contents were determined by the traditional Kjeldahl method.The optimal model dimension is found to be 5 by cross-validation.22 millet samples were determined by the proposed FTNIR-PLS method.The correlation coefficient between the concentration values obtained by the FTNIR-PLS method and the traditional Kjeldahl method is 0.9805.The standard error of prediction(SEP)is 0.28% and the mean recovery is 100.2%.The proposed method has been successfully applied for the routine analysis of protein in about 10,000 grain samples.

Application of Short-wave Near-infrared Reflectance Spectroscopy in Controlling Extract of Fructus Cnidii Using Supercritical Carbon Dioxide

Fructus cnidii （Chinese name shechuangzi） is the fruit produced by Cnidium monnieri （L.） Cusson （Umbelliferae）. It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharmacological studies have revealed crude extracts or components isolated from fructus cnidii possess antiallergic, antipruritic, antidermatophytic, antibacterial, antifungal, and antiosteoporotic activities. Osthole and imperatorin are the major compounds present in shechuangzi. They are often used as standards for the evaluation of the quality of shechuangzi products.

Titanium dioxide as an adsorbent to enhance the detection ability of near-infrared diffuse reflectance spectroscopy

A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective enrichment of fsDNA was proved by comparing the adsorption efficiency of bovine serum albumin,tyrosine and tryptophan,and the low adsorption background of TiO2 was illustrated by comparing the spectra of four commonly-used inorganic adsorbents(alkaline aluminium oxide,neutral aluminium oxide,nano-hydroxyapatite and silica).The spectral feature of fsDNA can be clearly observed in the spectrum of the sample.Partial least squares(PLS)model was built for quantitative determination of fsDNA using 28 solutions,and 13 solutions with interferences were used for validation of the model.The results showed that the correlation coefficient(R)between the predicted and the reference concentration is 0.9727 and the recoveries of the validation samples are in the range of 98.2%-100.7%.

Determination of Cysteine Using Near-infrared Diffuse Reflectance Spectroscopy with Enrichment via Thiol-maleimide Click Reaction

Enrichment technique has been proved to be an efficient way to make the near-infrared diffuse reflectancespectroscopy（NIRDRS） suitable for micro analysis. However, low selectivity presented by conventional enrichmentmethods makes the quantitative analysis easy to be affected by the coexisting components. In this study, a specificenrichment method with chemical bonding via thiol-maleimide click reaction was used to achieve the reduction of theinterferences. Taking cysteine as the analyzing target, maleimide-functionalized SiO2 nanoparticles were prepared forthe enrichment of cysteine. Then determination of cysteine in aqueous solution and human serum was studied usingthe partial least squares model built from the NIRDRS spectra of the adsorbate. The results show that the concentra-tion that can be quantitatively detected is as low as 2.0 μg/mL, and the correlation coefficient（R） between thereference and predicted concentration is 0.9871 for the validation samples. The recoveries are in the range of89.5%-113.8% for human serum samples in the concentration range of 0--16.2 μg/mL.

Determination of triglycerides in human serum by near-infrared diffuse reflectance spectroscopy using silver mirror as a substrate

Near infrared diffuse reflectance spectroscopy(NIRDRS) has gained wide attention due to its convenience for rapid quantitative analysis of complex samples. A method for rapid analysis of triglycerides in human serum using NIRDRS with silver mirror as the substrate is developed. Due to the even and high reflectance of the silver mirror, the spectral response is enhanced and the background interference is reduced.Furthermore, both linear and nonlinear modeling strategies were investigated adopting the partial least squares(PLS) and least squares support vector regression(LS-SVR), continuous wavelet transform(CWT)was used for spectral preprocessing, and variable selection was tried using Monte Carlo uninformative variable elimination(MC-UVE), randomization test(RT) and competitive adaptive reweighted sampling(CARS) for optimization the models. The results show that the determination coefficient(R) between the predicted and reference concentration is 0.9624 and the root mean squared error of prediction(RMSEP) is 0.21. The maximum deviation of the prediction results is as low as 0.473 mmol/L. The proposed method may provide an alternative method for routine analysis of serum triglycerides in clinical applications.

不同种丹参药材的近红外漫反射光谱模式识别法鉴别

目的 :建立近红外漫反射光谱 (NIRDRS)鉴别不同种丹参药材的方法。 方法 :对 9个产地的丹参药材和同属其他 9种植物 ,采用模式识别法中的聚类分析和判别分析方法进行定性鉴别。 结果 :丹参药材的 NIRDRS原谱及一、二阶导数光谱较为相似 ,无法直观鉴别 ;聚类分析发现同种不同产地的丹参较同属不同种药材具有更大的 NIRDRS相似性 ;判别分析发现 ,特征向量投影法映射图可以直观鉴别不同种丹参药材 ,结果与化学成分测定相一致。 结论 :该方法简便、快速 。

蝼蛄的近红外光谱鉴别研究

目的 :对蝼蛄的不同种和异地的同一种以及混乱品种进行鉴定、分析。方法 :应用傅立叶变换近红外光谱仪。结果 :聚类分析表明不同的蝼蛄种间聚类关系较远 ;虽异地但为同一种的蝼蛄聚类关系较近 ;相近地理位置所产蝼蛄 ,其聚类关系较近 ;混乱品种蟋蟀和东方蝼蛄的聚类关系较近。结论 :近红外分析法可应用于蝼蛄种的分类以及蝼蛄药材的分析、鉴定。

近红外漫反射光谱法快速检测谷子蛋白质和淀粉含量

建立近红外漫反射光谱法测定谷子中的蛋白质和淀粉含量,提供一种快速、简便、无损的分析方法进行谷子品种资源鉴定和筛选。以191份山西核心谷子种质为材料,采用近红外漫反射光谱法建立谷子蛋白质和淀粉含量的快速检测模型。结果表明,采用一阶导数+矢量归一化光谱预处理,分别建立谷子蛋白质和淀粉含量的校正模型,模型的校正决定系数(R^2_(cal))分别为0.977 0和0.907 3,交叉验证均方根误差分别为0.203%和0.466%,外部验证决定系数(R~_(2val))分别为0.989 6和0.977 2,预测均方根误差分别为0.225%和0.368%。对于谷子蛋白质和淀粉的预测,化学法和近红外仪器法测定间无显著差异,近红外测定结果是准确可靠的。说明采用近红外漫反射光谱分析技术能够满足对谷子蛋白质和淀粉含量的检测。

近红外漫反射光谱聚类分析用于中药红曲的鉴别

目的:建立用近红外漫反射光谱法鉴别中药红曲的方法。方法:采用聚类分析方法进行定性鉴别。结果:有效地鉴别了不同种的红曲,结果与形态学、扫描电镜的检验结果一致。结论:近红外漫反射光谱法快速、简便、低耗,可用于红曲等中药的质量控制。

氨酚伪麻片中对乙酰氨基酚和盐酸伪麻黄碱的近红外法测定

采用近红外漫反射光谱法结合小波变换-人工神经网络算法,用于氨酚伪麻片中对乙酰氨基酚和盐酸伪麻黄碱的无损含量测定。光谱预处理采用一阶导数,于8000～4000cm-1波段建模。对乙酰氨基酚和盐酸伪麻黄碱预示集平均回收率分别为99.6%和98.8%,RSD分别为2.0%和3.3%。t检验结果显示,本法所得结果与HPLC法无显著性差异。

复合近红外光谱法在牛奶测定中的应用

研究了用于快速测定牛奶主要成分含量的近红外透射光谱法和漫反射光谱法,分析了两种方法在实际测量中的差异,并提出将两种方法结合形成复合光谱法用于牛奶成分含量的检测。结果表明:复合光谱法的应用有效地提高了多变量回归分析中牛奶成分含量的预测精度。

近红外漫反射光谱聚类分析法在通光藤鉴别中的应用

目的研究中药通光藤的有效鉴别方法。方法利用近红外漫反射光谱法,采用聚类分析方法进行定性鉴别。结果在此条件下可实现通光藤不同产地、不同部位的有效鉴别。结论本法是一种快速、简便、低耗的新型分析技术,为科学评价通光藤药材质量提供了依据。

小波变换-人工神经网络用于烟酸片的近红外快速、无损定量测定

目的：研究采用近红外漫反射光谱法结合小波变换-人工神经网络算法用于烟酸片的无损含量测定。方法：所有光谱通过载有InGaAs检测器和光纤探头的傅立叶变换近红外装置获得。所有样品在12000cm^-1到4000cm^-1扫描，每个样品光谱扫描64次，光谱预处理采用一阶导数。特定波段7999．599～3999．8cm^-1用于建模，线性范围：50％～150％。结果：预示集平均回收率100．06％，RSD％为1．5。为确证近红外漫反射光谱法应用的可行性，预示集与参比方法紫外分光光度法测定结果进行比较，采用配对比较t检验，近红外法与紫外光谱法比较无显著性差异。结论：近红外漫反射光谱法快速，简便，无损，能够用于烟酸片含量测定。

近红外漫反射光谱法非侵入式定量分析盐酸氨溴索片剂

目的 建立非侵入式检测盐酸氨溴索片剂待压颗粒、裸片及铝塑包装片的方法。方法 应用傅立叶变换近红外光谱仪和外接积分球、旋转测样器及固体光纤探头 ,颗粒样品采用PbS检测器 ,裸片及铝塑包装片采用InGaAs检测器 ,在 12 0 0 0～ 4 0 0 0cm- 1 ,每份样品扫描 6 4次求平均值 ,通过PLS法建立模型 ,待压颗粒、裸片、铝塑包装片建模采用波段分别为 4 6 0 2～ 4 2 4 7,12 0 0 0～ 74 98和 6 10 2～ 5 4 4 6 ,12 0 0 0～ 5 4 4 6cm- 1 。结果 交互证实法确定待压颗粒、裸片及铝塑包装片最佳主成分数均为 6 ,均方误分别为 0 30 6 ,0 972和 1 4 92。待压颗粒、裸片及铝塑包装片预示集主药盐酸氨溴索平均回收率分别为 10 0 % ,10 0 %和 10 2 % ,回收率RSD分别为 1 17% ,1 70 %和 1 78%。结论 近红外漫反射光谱法简便、快速、可靠 ,完全可应用于盐酸氨溴索片剂待压颗粒、裸片及铝塑包装片的快速无损定量分析 。

近红外漫反射光谱聚类分析用于血竭的鉴别

建立用近红外漫反射光谱法鉴别血竭的方法,采用聚类分析方法进行分类鉴别,快速、准确地鉴别了不同产地的血竭。近红外漫反射光谱法快速、简便、无损,可用于血竭等中药的分类鉴别。

酚咖片中对乙酰氨基酚和咖啡因的近红外漫反射光谱法测定

建立了近红外漫反射光谱法测定酚咖片中对乙酰氨基酚和咖啡因的含量。以HPLC法所得结果作参比,采用偏最小二乘(PLS)回归法建立了一阶导数光谱与两组分含量间的定量校正模型。并从光谱范围、导数光谱及PLS主因子阶数对模型进行了优化。

格尔木地区沙尘气溶胶铁氧化物漫反射光谱分析

格尔木地区沙尘气溶胶漫反射光谱分析显示该地区沙尘气溶胶反射光谱的一阶导数曲线分别在波长430,560 nm处存在两个明显的特征峰值,可用于指示粉尘样品中的赤铁矿和针铁矿的相对含量.红色、橙色和黄色反射率随赤铁矿和针铁矿可见光谱一阶导数特征值增加而增大,而蓝色、紫色和绿色反射率则相应减小,表明赤铁矿和针铁矿是格尔木沙尘的重要致色矿物,对沙尘气溶胶光学特性产生重要影响.格尔木地区沙尘气溶胶中赤铁矿和针铁矿相对含量变化受沙尘过程影响,沙尘天气时赤铁矿和针铁矿可见光谱一阶导数特征值明显增高,指示铁氧化物的相对含量增高.赤铁矿和针铁矿可见光谱一阶导数特征值及两者比值在不同地区粉尘样品中有很大差异,表明赤铁矿和针铁矿可见光谱一阶导数特征值及两者比值具有较强的源区指示意义.