Automatic melting point Digipol-M70 trehalose detection application scheme

I. Introduction Trehalose, as a kind of natural sugar, exists widely in a variety of edible animals, plants and microorganisms. Its unique molecular structure, composed of two glucose molecules with 1, 1-glucoside bond to form a non-reducing sugar, with α,α,β,β and α,β three isomers. Trehalose plays a key role in many fields due to its outstanding ability to maintain the stability and integrity of intracellular biofilms, proteins and active peptides. In the food industry, it can prevent starch aging, protein denaturation, inhibit lipid oxidation, maintain the stability of food tissue, and provide lasting and stable energy for food; In the pharmaceutical industry, it can be used as a stabilizer for reagents and diagnostic drugs, and is used to preserve bioactive substances such as vaccines and haemoglobin. In the cosmetics industry, it has moisturizing, sunscreen and other effects, and is often added to various skin care products; In crop breeding, the introduction of trehalose synthase genes can improve crops and can also be used for seed preservation. Due to the importance of trehalosaccharide, the accurate detection of its melting point is of great significance to ensure the quality and characteristics of the product, and the fully automatic melting point meter Digipol-M70 from Shanghai Jiahang provides a reliable means of detection. 2. Experiment preparation 2.1 Test equipment Digipol-M70, a fully automatic melting point instrument from Shanghai Jiahang, uses advanced optical and electronic technology, with a high-precision temperature control system and intelligent detection function. It is equipped with a high-resolution imaging system, which can clearly capture the state change of the sample during the heating process; Equipped with a high-performance processor, it can process data quickly and accurately determine the melting point. In addition, the instrument operation interface is simple and intuitive, which is easy for users to set and operate parameters. Capillary: Choose a capillary with an outer diameter of 1.1mm, an inner diameter of 0.9mm, and a length of 100mm. This specification of capillary tubes meets the requirements of conventional melting point detection, ensures uniform sample heating, and facilitates the observation of the melting process of the sample. 2.2 Experimental Samples Trehalose (non-reducing disaccharide) with high purity was selected as the experimental sample. Ensure that samples are not contaminated during storage and access, and ensure the accuracy of experimental results. 2.3 Reference Standards "GB/T 23529-2009 trehalose" was used as the reference standard for this experiment. The standard specifies the technical requirements, test methods, inspection rules, marking, packaging, transportation and storage of trehalose, and provides a standard and basis for trehalose melting point detection. 3. Experimental steps 3.1 Sample Test Sample drying: Use a weighing bottle that has been baked to constant weight to accurately weigh the trehalose sample of about 2g. Place the weighing bottle in an electric drying oven at 90 ° C ±1 ° C for 5 hours. The drying process can remove moisture from the sample to avoid interference with the melting point test results. After drying, cover in time to prevent the sample from absorbing moisture in the air, and then cool to room temperature for use. Sample grinding: The dried trehalose sample is placed in a mortar and quickly ground. Through rapid grinding, the sample is made into a uniform and fine powder, which ensures that the sample is heated evenly during loading and heating, and improves the accuracy of the test results. Reserve after grinding. Sample loading treatment: The treated trehalose powder is loaded into a clean, dry capillary tube. Take a dry glass tube about 1 meter long and open at both ends and stand vertically on the glass plate. Insert the capillary tube containing the sample through the upper mouth of the glass tube and let it fall freely in the glass tube several times. In this way, the sample inside the capillary tube is compact and firm, and the loading height is controlled at about 3mm. The appropriate loading height can not only ensure that the sample is fully heated, but also facilitate the observation of the melting of the sample. Instrument parameter setting: Open the automatic melting point Digipol-M70, find the "preset temperature" option on the instrument operation interface, and set the preset temperature to 210℃. The preset temperature is usually set to about 5 ° C lower than the estimated actual melting point, which can reduce the waiting time and improve the detection efficiency. In the heating rate setting option, select a heating rate of 0.5 ° C /min. The lower heating rate allows the sample to heat slowly and evenly, and the melting point can be determined more accurately. Sample melting point determination: Carefully place 3 capillary tubes containing trehalose samples into the furnace core of the instrument. Click the "Temperature rise" button on the instrument operation interface, and the instrument starts to raise the preset temperature to 210 ° C. During the heating process, the instrument will display the core temperature in real time. When the core temperature reaches the preset 210℃, press the "temperature rise" button again, and the instrument continues to heat up at the set rate of 0.5℃/min. At this time, the imaging system of the instrument will capture the melting process of the sample in real time, and the intelligent detection system will automatically judge and record the initial melting point and the final melting point according to the state change of the sample, waiting for the instrument to complete the measurement and display the final result. 4. Results and discussion 4.1 Test Interface The Digipol-M70 automatic melting point tester has a simple and clear test interface, which is easy to operate and observe. Key information such as the current core temperature, preset temperature, start temperature, and end temperature are displayed on the interface in real time. In the sample measurement area, the measurement status of the sample in the three capillary tubes is clearly displayed, including whether it is being measured and the progress of measurement. After the measurement is completed, the initial melting point and final melting point data of each capillary sample are automatically displayed. At the same time, the chart of the measurement results can be generated to directly show the temperature change trend during the sample melting process. In addition, the interface is equipped with data storage, query and print function buttons, which is convenient for users to manage and analyze the measurement data. 4.2 Experimental Results After many measurements (assuming 5 measurements), the following experimental data are obtained: Number of measurements Initial melting final melting 1 214.5 215.4 2 214.4 215.2 3 214.5 215.1 4 214.6 215.2 5 214.5 215.3 4.3 Discussion As one of the important physical properties of substances, melting point is a key method to identify the nature and determine the purity of substances in the field of organic chemistry. For trehalose, accurate melting point data can reflect its purity and quality. If the trehalose contains impurities, it will lead to a lower melting point or a wider melting range. By using Digipol-M70 automatic melting point instrument of Shanghai Jiahang to detect trehalose, precise melting point data was obtained. Using advanced optical imaging and intelligent detection technology, the instrument can measure samples in three capillary tubes at the same time, which effectively improves the detection efficiency and the accuracy of results. The function of automatically recording the melting image and calculating the average melting point reduces the human error. The temperature control system adopts a high-precision temperature sensor to ensure the stability and accuracy of the heating process, further improving the reliability of the melting point detection. The instrument has a variety of measurement modes and flexible parameter setting functions, which can meet the measurement needs of different users and samples, and provide strong support for the quality control and research of trehalose.