使用NIR快速识别非法药物（MDMA片剂的识别）

与中红外分析相比，近红外（NIR）光谱具有独特的能力，中红外分析通常需要大量的样品制备才能获得可识别的光谱。因此，根据所需的分析，NIR可用于特定样品区域的非破坏性分析或提供较大样品区域的平均值。近年来，近红外光谱已被广泛用于生物样品的检测以及食品和医疗产品的质量控制/分析。漫反射技术是这种方法的理想选择，因为样品处理极其简单，因此可以通过使用使用近红外漫反射创建的搜索数据库来快速识别非法药物，如MDMA。漫反射附件（VIR-NRF-N）与便携式傅里叶变换近红外光谱仪（VIR-9650）结合使用，然后简单地将MDMA直接放置在样品支架上，可以在不需要进一步的样品制备的情况下进行测量。一种InGaAs探测器被用于提供增强的灵敏度和快速扫描能力。采用主成分分析（PCA）来简化MDMA片剂的阳性鉴定。通过对算法、计算参数和对随机选择的药片搜索结果的比较所建立的阈值的研究，验证了简单识别系统的实用性。应用中图1显示了安装在VIR-9650中的漫反射系统的照片。将药片直接放置在样品架上，如应用中图2所示。如果是非常小的药片，不能放置在支架上，则将样品放置在如应用中图3所示的试管中，并进行测量。我们已经证明了利用主成分分析鉴别的近红外分析方法用于鉴定各种药物制剂。近红外系统展示了一种用于各种片剂的快速、无损分析方法，该方法可以扩展到提供药物浓度的定量分析。Application NoteNo.200DR0188-E No.200DR0188-E UAS.C O Rapid Identification of an Illegal Drug using NIR (Identification of MDMA Tablet) Introduction Near-Infrared (NIR) spectroscopy has unique capabilities as compared to mid-infrared analysis which can often require extensive sample preparation to obtain an identi f iable spectrum. As such， NIR can be useful for the non-destructive analysis of a specif i c sample area or provide an average of a larger sample area， depending upon the required analysis. In recent years， NIR spectroscopy has been widely used for the examination of biological samples and quali t y control/analysis of food and medical products. The diffuse reflectance technique i s ideal for this method due to extremely simple sample handling such that rapid identificat i on of illegal drugs， such as MDMA， can be accomplished by using a search data l ibrary created using NIR diffuse reflectance. A d dif f use reflection accessory (VIR-NRF-N) is used 1in combination with a portable Fourier Transform Near-Infrared Spectrometer (VIR-9650) and then by simply placing a t ablet，such as MDMA， directly on the sample holder， a measurement can be performed without further sample preparation.An InGaAs detector i s used to provide enhanced sensitiv i ty and a rapid scanning capabi l ity. Principal Components Analysis (PCA) was performed to simplify positive i dentification of an MDMA tablet. When the possible grouping of spectral data was confirmed based on the PCA program， a library was established. For establishing the PCA data l i brary， 40 t ypes of tablets were analyzed， namely 25 types of over-the-counter pharmaceuticals， such as gastrointestinal drugs， one type of amphetamine (AP)， eight types of MDMA (street name：ecstasy)， three types of methamphetamine (MA)， and three types of MDA (street name： the love drug). The utility of a simple e identificationsystem Wa L s Sexamined by the investigation of the algorithm， the calculation parameters and a threshold established from comparison of the search results from randomly selected t ablets. Figure 1 shows a photo of the diffuse reflection system installed i n the VIR-9650. The tablets were placed on t he sample holder directly， as shown i n Figure 2. In t he case of an extremely small tablet ， unable to be placed on the holder， the sample was placed in a test tube like the one shown i n Figure 3， and measured. Figure 2： Measurement of a tablet Figure 1： VIR-9650 and the diffuse reflection accessory Figure 3： Measurement of crushed and powdered samples Figure 4 illustrates the PCA analysis results for an MDMA tablet . Figure 5 includes examples of the Near-Infrared spectra for the 4 classes of i llegal drugs. Sample identification can be accomplished by using the region (indicated by the arrow)where t he spectral absorptions can provide specific peaks depending on the t ablet component. The PCA method， however，les dist i nct discrimination between the various drug components due to subtle variations in the NIR spectra. Since NIR spectra do not provide specific discriminatory peaks l i ke mid-IR spectra， the PCA A method 1offersan nenhanced discrimination of the various drug components， strengthening the identification of the ‘unknown’drug tablet. The NIR diffuse reflection system i s ideal as a rapid analysis method because the tablet is simply placed on the accessory platform and the CESSOIY required sample measurement time is only 10 seconds. This method wi l l become more powerful for sample identi f ication as the library data is expanded with additional standard sample data. Figure 6 demonstrates a calibration model i llustrating the correlation between tablets containing MDMA and quantitative results of these tablets using GC analysis. With a correlation coefficient of R=0.966， these results demonstrate a sufficient correlation for performing sample quantitation.This would make it possible to analyze the amount of MDMA in i llicit tablets by l inking t he search results of the ident i fication program with the calibration model developed using GC analysis. Figure 7 i s an example of the program developed for the identification of the drug formulations using the PCA search method. Conclusions We have demonstrated the use of a NIR analysis method uti l izing PCA discrimination for the ident i fication of various drug formulations. The NIR system demonstrates a rapid， non-destructive analysis method for various drug tablets that can be extended t I o O provide quantitative analysis of the e drug concentration. Figure 5： Diffuse reflectance spectra of various street drugs Figure 4： PCA analysis results for street drugs Figure 6： Calibration curve of NIR and GC results for MDMA Figure 7： Confirmation t est and quantitative analysis results