Fluorometric method based on molecular recognition solid-phase extraction for determination of riboflavin in milk and infant formula

Riboflavin (vitamin B₂) is involved in several biological processes, particularly in energy production, and it is acquired from food ingestion, principally from supplemented food during the first years of life. Therefore, a simple, fast and cost-effective high-throughput method for determination of riboflavin in milk and infant formula is proposed, based on selective extraction using commercially available molecularly imprinted polymers targeted to riboflavin, followed by direct fluorometric determination. Several aspects were studied, namely microplate assay conditions, the composition of eluting solution and the stability of riboflavin in the eluate. Hence, elution using 1% (v/v) acetic acid in methanol or in acetonitrile is recommended, followed by immediate analysis or solvent evaporation, with reconstitution and analysis within 24 h. The proposed method provided a LOD of 0.03 mg L⁻¹, with working range for undiluted samples between 0.125 and 2 mg L⁻¹, and sample throughput of 24 h⁻¹. It was successfully applied to certified reference material NIST-1846 and also to commercial milk and infant formula samples.     

中国生育政策的文本量化分析——基于政策工具、政策包容性、政策力度的三维分析框架

目的：对我国实施全面二孩政策以来的生育政策进行文本量化分析,为完善我国生育政策提供建议。方法：检索2016年以来发布的国家层面的生育政策文本,构建政策工具、政策包容性、政策力度三维分析框架,并对政策文本进行多维度及交叉对比分析。结果：本文共纳入45份政策文本,命令及规制性工具、能力建设性工具、激励性工具和信息及劝诫性工具占比依次为50.90%、39.16%、9.34%和9.94%;政策文本在尊重生育理念、促进生育公平、提升社会福祉三个政策包容性类型上分别占比12.14%、20.39%、67.48%;我国生育政策力度平均得分为2.67。结论：生育政策的政策工具内部均衡性不足,激励性与信息及劝诫性工具的使用有待加强;政策包容性类型丰富但使用不均衡,需要进一步促进性别平等和生育公平;政策力度整体偏弱,且与政策主体协调性不足,应进一步深化多部门参与协作,从财政、教育、文化等多个层面落实好生育配套措施,创建生育友好型社会。