使用NRS-4100拉曼分光光度计测量嵌入异物

目前，红外显微镜被广泛用作识别样品基质中微观污染或异物的方法之一。红外光谱法已经建立了一个庞大的已鉴定样品光谱数据库，是鉴定未知异物的理想方法。然而，红外显微镜的缺点是，测量的空间分辨率仅限于几微米，并且如果目标材料埋在样品内，则可能需要大量的样品制备。激光拉曼光谱是一种与红外显微镜相结合被广泛用于测量异物的技术。本应用中总结：NRS-4100可以以非接触和无损的方式测量包埋样品，而不需要广泛和困难的样品制备。利用拉曼结合红外显微镜，可以更容易地完成对更复杂的异物的分析。Application Note 2/5Application NoteMeasurement of embedded foreign material using an NRS-4100 UAS.G O Measurement of embedded forei g n material usin g an NRS-4100Raman Spectrophotomete r Introduction Currently， infrared microscopy is used extensively as one of the method s for ident i fying microscopic contamination or foreign materials in a sample matrix . Infrared spectroscopy has well established and l a rge database o f identified sample spectra and is ideal for the identificat i on of unk n own foreign materials. However， the drawbacks of in f rared microscopy are that the measurement has a spatial resolution limited to only a few micrometers and extensive sample preparation can be required if the target material is buried inside the sample. Laser Raman spectroscopy is a technique being widely adopted for measurement of foreign materials in combination with infrared microscopy. Keyword ： Raman， Confocal Raman Analysis Polymer analysis， NRS-4100， Terpene resin Cellulose， Glass 28600 Mary's Court， E a ston， MD 21601 USA Raman spectroscopy is similar to IR microscopy in that i t can identify molecular structures by analyzi n g molecular vibrations， but Raman spectroscopy offers several key advantages . 1. Excellent spat i al resolution down to 1 pm using a visible laser. 2. Raman spectroscopy offers quick and easy non-destructive measurement without sample pretreatment. 3. Identi f ication of inorganic samples is s i mpli f ied because sample measurements can be obtained i n a low wavenumber range (below 400 cm-1). The potential for measuring foreign materials using Raman spectroscopy is expanding， and JASCO has developed a new， compact， easy to use l aser Raman spectrometer.T he JASCO NRS-4100 is designed to be used as a complement a ry technique to FTIR microscopy. I n this application note， we wil l illustrate some of the key features of the NRS-4100 for the ident i fication of foreign materials buried in a polymer film. Features of the NRS-4100 The NRS-4100， as shown in Fig . 1， is a Raman spectrometer， incorporating a high performance spectrograph， sample compartment， detector and lase r l ight source in a very small optical bench just 60 cm square， which can be installed on a standard laboratory bench (no requirement for an ant i -vibration table).The instrument requires no extra space as the sample compartment door moves up and down for open/close operations. In addition， the NRS-4100 meets t h e Class 1 laser safety standard. Up t o three lasers， including the standard conf i guration o f 532/785 nm plus a compact 457 nm laser can be installed inside the instrument . The spatial resolution for the NRS -4100 is as small as only 1 pm in the XY and 1.5 pm in the Z direction， enabling high spatial resolut i on and fluorescence min i mization， which are important for the measurement of foreign materials. The “Measurement Assist” function aids the user in sett i ng up the NRS-4100 for sample measurement； a s i mple sequence guide takes the user through setup and optimization of measurement parameters with helpful advice and t ips， such as a warning if the laser intensity set too high. The new“Sample Search”func t ion is used with the automated XYZ stage. A new a l gorithm developed by JASCO (patent pending)analyzes the microscopic i mage and automatically selects measurement position(s) based on the size，contrast and/or color of the target material d e scribed by the user， then simply click the measurement button to execute spec t ral measurements o f the automat i cally identif i ed sample positions. Spectra Manager II incl u des a weal t h of user-selectab l e options for data analysis ， as well as the usual tools like opening single or multiple spectr a ， zooming， normalization ， a variety of ari t hmetic data processing functions and in c ludes an array of Raman specific tools and analysis functions. System configuration NRS-4100 Raman Spectrometer Automatic imaging system Foreign material measurement/Analysis The foreign material embedded in the m ult i layer substrate (glass/adhes i on layer/transparent f ilm) shown in Fig. 3 was measured. I t is difficult to measure such foreign material using an infrared microscope because i t is difficult to cut t h e foreign mater i al into a cross-section due to the presence of glass and the adhesion layer， which may resul t i n the two materials being sampled together. On the other hand， a Raman instrument with a confocal optical system can select i vely obtain a spectrum of the sample at the focused laser point. As a result， i t is possible to measure the inside of the sample i n a non-contact and non-d e struct i ve mann e r without dif f icul t and t ime-consuming sample treatment . In this report ， the posi ti on where the target foreign material is located was measured by depth profiling (Z axis direction) and the spectral information for each layer was obtained. The major spectra obtained from each l ayer is shown i n Fig. 4. Measurement parameters 532 nm 900 gr/mm Fig . 3 Observat io n i mage Fig.4 Spec t rum fo r each la y er In the spectrum obtained of the foreign material ， a C-H peak at around 3000 cm-1 is not shown and thus it is quite different from the spectra of the t ransparent film and adhesion layers. In order to analyze the result in further detail ， the spec t rum o f the foreign material was searched and identified using a database as shown in Fig. 5， and the foreign mater i al was found to be talc (hydrated magnesium silicate). In addi t ion， it is known that the transparent f ilm is made of cellulose and the adhesion layer is made o f a terpene resin. Fi g. 5 Search r e s u l t of the database Summary NRS-4100 can measure embedded samples in a non-contact and non-destructive manner without the requirement for extensive and difficult sample preparation. By using Raman i n combination with an I n frared microscope， the an a lysis of more complex foreign mater i als can be easily accomplished.