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Benefits of forced degradation test The degradation pathway of the drug is closely related to the molecular structure of the drug. The ester group or amide bond in the molecular structure may be hydrolyzed under acid-base catalysis conditions. Provide support for drug safety. When toxicologically relevant impurities are not readily available, toxicological evaluation of samples degraded to a certain extent can provide a supportive basis for drug safety and impurity limit determination. It is helpful for metabolite research. Some degradation products are also metabolites, and the metabolites produced by degrading test samples can be used for confirmatory studies and analysis. Contribute to the development of active pharmaceutical ingredient (API) technology, formulation process, and the screening of drug salt and crystal forms. When the degradation impurities have toxic structures, the production of impurities can be avoided by changing the process route. The process parameters can also be controlled to ensure that the impurities are at an acceptable level. The forced degradation results of different crystalline and salt forms of drugs can indicate their stability. Guide the development of drug packaging systems and determine storage conditions. Degradation test results can suggest drug susceptibility factors. The results of forced degradation testing, influencing factor testing, accelerated testing, and long-term testing together support drug packaging and storage conditions. Purpose of forced degradation test The purpose of the forced degradation study is to understand the degradation products and degradation pathways of drugs under different destruction conditions. The forced degradation test can provide a useful reference for the establishment of analytical methods, the formulation of instructions and the determination of formulation design. Degradation pathways Aggregation Non-covalent aggregates are usually the result of mechanical stress (like shaking, stirring, rotating, pumping), and aggregation can also occur after repeated freezing and thawing, heating, or exposure to acidic pH environments. Aggregation can also be covalent in nature, such as chemical bonding between molecules, which are not dissociable during buffer exchange. These chemical bonds are usually formed by rearranged disulfide bonds or other altered intramolecular chemical linkages. They are usually the result of amino acid residues reacting with trace metals (copper or iron) or incomplete protein reduction. Oxidation The side chains of methionine, cysteine, histidine, tryptophan or tyrosine residues are prone to oxidation, with methionine being the most reactive residue. Oxidation can alter the physicochemical properties of proteins, such as folding and subunit association. Oxidative conditions are formed primarily by exposure to atmospheric oxygen, in the presence of light, heat, moisture, agitation or exposure to oxidants. Deamidation is the hydrolysis of asparagine or glutamine into free carboxylic acid residues, usually due to changes in pH, ionic strength, temperature and humidity of lyophilized proteins. The overall effect of chemical modifications to a single amino acid residue depends on its location in the protein and the specific role of the residue in the protein's functional and active site. Illumination photolysis by exposure to light involves and affects free radicals of many functional groups, such as carbonyl groups, which can lead to oxidation, aggregation, or cleavage of peptide bonds. Photolysis is caused by exposure to a certain amount of photoradiation, usually in the form of ultraviolet radiation. Hydrolysis Hydrolysis (cleavage) is the breaking of peptide bonds between amino acid residues, releasing smaller peptide chains. The peptide bonds of Asp-Pro and Asp-Gly are the most easily hydrolyzed. Hydrolysis is mainly caused by exposure to acidic or basic pH. CD Formulation is a leading manufacturer of a large variety of excipients. Driven by the latest science and technology, it has grown to be a reliable source for the pharmaceutical industry, offering not only rich collection excipients but also a wide range of preformulation, formulation, analytical and custom pharmaceutical excipients services. Always at the forefront of innovation, CD Formulation aims to address the challenges arising from pharmaceutical formulation, and in a much broader sense, hopes to advance the global medical business. ... View more

Plants are amazing chemical factories. They take sunlight and use it and carbon dioxide to make energy for themselves. They also make oxygen, which we breathe. But they also make substances that can help heal us. Traditional Chinese medicine, for instance, makes use of herbs that are thought to have healing properties. And some drug companies use plant substances to make medicines — the breast cancer drug tamoxifen comes from the bark of the Pacific Yew tree. Now comes word that plants could be even more useful. Researchers are reporting an advance in re-engineering photosynthesis to transform plants into solar-driven “bio-factories.” The result? The plants end up making ingredients, not only for medicines, but also for fabrics, fuels and other products, when exposed to sunlight. Poul Erik Jensen and colleagues point out that photosynthesis does more than generate oxygen and energy. It also produces a wealth of natural chemical compounds, many of which have potential uses in medicines and other commercial products. However, evolution has cordoned off those functions into separate areas of the plant’s cells. Chloroplasts, the packets of chlorophyll that make plants green, generate the energy, sugar and oxygen. Another structure, the “endoplasmic reticulum,” produces a wide range of natural chemicals. Their report describes how they moved an entire metabolic pathway needed to make natural bioactive chemicals to the chloroplast. “This opens the avenue for light-driven synthesis of a vast array of other natural chemicals in the chloroplast,” they say. In a nutshell, they could make cool compounds by just shining light on some cells. What do you think? Could this have a real impact on how we make many chemicals? Do you think this could be scaled-up easily? What are some challenges that this research could face? “Redirecting Photosynthetic Reducing Power toward Bioactive Natural Product Synthesis,” ACS Synthetic Biology *Journalists can request a PDF of the journal article by emailing newsroom@acs.org. Credit: iStockphoto/Thinkstock  Follow us: Twitter, Facebook ... View more

Carbon nanomaterials have been speedily developed due to their unique electronic, optical, thermal, mechanical, and chemical nature. ... View more

DIY-ing a mug with sublimation printing is a fun and easy project that allows you to personalize a plain ceramic mug with your own design or photo. Sublimation printing is a process that uses heat and pressure to transfer a special type of ink onto a polyester or polymer coated surface. The end result is a vibrant, long-lasting image that won't crack or fade over time. Here is a step-by-step guide on how to DIY a mug with sublimation printing. What are the benefits of sublimation ink Materials Needed: White ceramic mug Sublimation ink Sublimation paper Heat press machine or home oven Heat resistant tape Teflon sheet or baking paper Design or photo (printed on sublimation paper) Step 1: Preparing the Mug Clean the mug thoroughly to ensure that there is no residue or oil on the surface. Wrap the handle of the mug with heat resistant tape to protect it from the heat during the sublimation process. Step 2: Printing the Design Choose the design or photo you want to use for the mug and print it onto sublimation paper using a sublimation ink printer. Make sure the design is sized appropriately for the mug and is printed mirror image (reversed) so that it will appear correctly when transferred onto the mug. Step 3: Sublimating the Design Place the printed design face-down onto the surface of the mug, making sure that it is centered and straight. Place the mug with the design onto a Teflon sheet or baking paper to protect the surface of the heat press machine or oven. Close the heat press machine or place the mug and Teflon sheet or baking paper into the oven. Set the heat press machine or oven to the appropriate temperature and time settings for sublimation (usually around 400°F for 2-3 minutes). Once the time has elapsed, carefully remove the mug from the heat press machine or oven and let it cool. Step 4: Finishing the Mug Carefully peel off the heat resistant tape from the handle of the mug. Your DIY sublimation printed mug is now ready to use! Note: It is important to use a high-quality sublimation ink and paper to ensure the best results. Always follow the manufacturer's instructions for your heat press machine or oven and use caution when handling hot surfaces. In conclusion, DIY-ing a mug with sublimation printing is a fun and easy way to create a personalized, one-of-a-kind mug. With the right materials and a little bit of patience, you can create a unique, high-quality image that will last for years to come. ... View more

Pharmaceutical excipients are substances formulated together with active pharmaceutical ingredients (APIs) of the drug, and excipients account for most of the drug composition. ... View more