Enzyme catalytic processes, as an important part of modern biotechnology, play a crucial role in the fields of chemical engineering and medicine. 

The enzymatic catalytic process typically uses whole cells, enzyme preparations, or cell homogenates as catalysts to react with substrates. Most of these reactions are also accompanied by a coenzyme regeneration system, ultimately generating intermediate products such as chiral amines, chiral alcohols, or oxidizing a single chiral alcohol to form ketones. The ultimate goal is to achieve resolution or transformation. Currently, the common enzymatic catalytic intermediates or products on the market include: D-amino acids, L-tert-leucine, sitagliptin intermediates, chiral sacubitril intermediates, the chiral side chain of paclitaxel, L-carnitine, L-dopa, L-clopyralid, florfenicol, methionine, etc. 

The enzyme-catalyzed process has the advantages of safe, environmentally friendly and green synthesis. However, the enzymes, host proteins produced by microorganisms, host DNA, and other components used in the production process may be transferred to the final product raw materials, thereby causing potential sensitization effects. To ensure the safety, effectiveness and controllability of the products, the National Medical Products Administration has strict regulatory requirements for the production processes of pharmaceutical intermediates and raw materials, especially for the strict control limits of enzyme proteins and host proteins.

Controlling protein residue is a crucial step in ensuring product quality. Membrane filtration technology, due to its high efficiency, energy saving, and simple operation, has become one of the effective methods for removing enzymes and proteins by ultrafiltration. Through physical sieving, membrane filtration separates target substances based on molecular size, effectively retaining large protein molecules; the permeate liquid is collected to obtain small-molecule products without proteins. 

By using membrane filtration, most of the pigments and large molecular impurities can be removed. The step of recrystallization can be eliminated, reducing the usage of acids, bases and activated carbon, shortening the processing time, and minimizing the loss of products. As a result, products with high content, high yield and high purity can be obtained.

Wuhan Bona, as a leading enterprise in the field of biological technology separation and purification, has significant advantages in membrane filtration technology. Based on its many years of engineering experience, the company uses advanced membrane materials and optimized filtration processes to provide customized filtration solutions for customers. It can not only effectively remove protein residues in pharmaceutical intermediates to ensure that the products meet the high standards of the pharmaceutical industry, but also, by considering the properties of the materials, the characteristics of the liquid, the selection of membranes and equipment, it can ensure the continuous and stable operation of the production process and realize the commercial production of industrialized products.