UV/VIS Excellence Spectrophotometers: How-to Videos

Welcome from our Mettler Toledo application lab in Switzerland. In this video I will demonstrate you how to set up the photometric method for measuring the absorbance at several wavelengths and how to calculate multiple results. As an example I have chosen the analysis of olive oil samples from our application library. Let's start with a method configuration. To create a new method, click Methods and select Fixed Wavelength. By clicking New, the method configuration is started. If we want to measure multiple samples, we can activate multiple determination and define whether we want to measure a closed or open sample series. Now we can see the method editor. In the first step, we have to define our wavelength of interest. For this application, we need the absorbance at four different wavelength: 232 266 270 and 270 and 409 liters. Since the absorption coefficient calculation formula takes into account the concentration of olive oil sample, we need to define a sample factor to change this value for each sample. To do so, we can click SAMPLE and define one sample factor with the name CONCENTRATION. This sample factor can be used later in the calculations as a flexible value. We confirm with OK to go back to the method editor. A new fixed wavelength method always contains one method function called Calculation. We have now to adjust and add further calculations according to the norm. We can click Calculation and first change the name to K232. The unit is 100 milliliter per gram and centimeter. To calculate the extinction coefficient The measured absorbance is divided by the concentration and the path length. The concentration is the previously defined sample factor. Under proposal various predefined calculation can be found. Further details can be found in our formula collection. Please ask your local Mettler Toledo sales representative for additional support. The number of decimal places can be adjusted to two. We can confirm our input with clicking OK. The norm requires three more extinction coefficients at the additional wavelength. To add further calibration steps, we can click on Insert and behind R1 again on Insert. The new calculation will be performed at this point within the method. The definition is the same as before and will be skipped in this video. Now you can see in the method editor four method functions calculation. To fulfill the norm, a fifth calculation has to be done. For this, we can insert again a calculation step. The result name is Delta K. And the unit is 100 mL per gram in centimetre. To calculate delta K we have to use the results of the previous calculations. Here you can see which result corresponds to which abbreviation. With this information, we can now set up the last calculation, R3 minus the sum of R2 plus R4 divided by 2. The number of decimals can be reduced to 2 again. Now we have defined all calculations. We can now select which result should be shown on the screen. We have calculated five results and all of them can be shown on the results screen after the measurement using five result fields. After saving we are ready to start the method. You can click start and have to define our concentration. which is 0 .992, based on my sample preparation. You have the possibility now to save the method to your home screen with Add to Home. This will create a shortcut on the home screen and is highly recommended for frequently used methods as they can be started with one click. For this, you have to define a name, for example olive oil. By saving it you will end up on the home screen. Just click the shortcut, returning to the same screen as before. Now you can define sample ID and change the dilution and correction factor if you need to. After clicking you are guided through the workflow. First we have to insert the blank case. By clicking OK, the blank determination starts. Afterwards, we are asked to insert the sample cuvette. By confirming this pop-up, the measurement starts again, and the results are shown on the screen. I hope this short video was helpful understanding how to set up a fixed wavelength method with several calculation steps. The workflow is always similar, independent from the application. Thank you for watching this video. Don't miss our other videos explaining more measurement categories and how to get methods from our application library on mp.com.

嗯哼。 欢迎来到我们位于瑞士的 Mettler Toledo 应用实验室。在本视频中，我将向您演示如何使用 Mettler Toledo 的 UV7 excellent 分光光度计和 LabX UV-VIS 软件，轻松且正确地按照药典测定颜色。作为今天的示例，我将通过一个逐步教程，带您了解如何按照欧洲药典进行颜色测定。 在我们的 Pharma Color Guide 中，我会更详细地讲解颜色测定的理论。下载该指南后，您还将获得可直接使用的 LabX 方法，用于按照两部药典测量颜色。您可以在此下载该指南。那么现在让我们来到实验台，开始设置仪器。首先，我们需要将方法导入 LabX UV-VIS 软件。 为此，我们选择 Import LabX Method，并从目标文件夹中标记所需的方法。成功导入后，所选方法会显示在这里的分析选项卡中。由于欧洲药典颜色标尺是基于将测得的 CIE Lab 值与颜色标准的 CIE Lab 值进行比较，因此我们首先需要将所有参考值导入 LabX 数据库。 为此，我们需要执行相应的 Caleb table 方法。在这个示例中，我将只与标准棕色 P_ 进行比较。我们选择方法 EOP Caleb table B_，并在已连接的 UV7 分光光度计上启动任务。在任务编辑器中，我们上传棕色的任务参数文件。 任务参数文件是方法包的一部分，包含所有棕色色卡标准的参考值。点击 OK 后，该方法会在仪器上启动，参考值将存储到 Levix 数据库中。这些初始步骤只需执行一次。之后，这些数值将保留在数据库中。现在设置已经完成，我们可以按照欧洲药典测量样品了。 要开始样品分析，我们启动方法 UP 00B 并定义样品列表。确认后，方法会在仪器上启动。首先我们需要测量空白。我这里使用蒸馏水。空白确定后，系统会提示操作员插入第一个样品。 测量完成后，系统会显示与样品值最接近的颜色标准作为结果。希望这个简短的视频能帮助您了解如何按照欧洲药典测定颜色。美国药典的工作流程非常相似，而我们的 Pharma Color Guide 还提供了详细说明以及一些背景理论。 感谢您观看本视频，也别错过我们其他视频，其中介绍了各种测量类别，以及如何从 mt.com 上的应用库下载更多可直接使用的方法。