Polyethylene glycol modified rhBNP and preparation method thereof

The invention provides polyethylene glycol modified rhBNP and a preparation method thereof. Specifically, the invention provides a new polyethylene glycol modified rhBNP preparation method, and a corresponding polyethylene glycol modified rhBNP pharmaceutical composition is prepared on the basis of the method. According to the method disclosed by the invention, the specificity of N-terminal mono-pegylation of rhBNP and the product purity can be improved, and a basically uniform N-terminal single PEG modified rhBNP product can be obtained. 本发明提供了一种聚乙二醇修饰的rhBNP及其制备方法。具体地，本发明提供了一种新的聚乙二醇修饰的rhBNP制备方法，并基于该方法制备了相应的聚乙二醇修饰的rhBNP的药物组合物。本发明的方法可以提高rhBNP的N-末端单聚乙二醇化的专一性及产品纯度，可以得到基本均一的N-末端单PEG修饰的rhBNP产品。