Question: How to choose the extraction solvent in the study of the extraction performance of contact lens products?
Answer: It is recommended to choose the solvents recommended in Table 2 in GB/T11417.7 “Test Methods for Physical and Chemical Properties of Contact Lenses”. It is recommended to choose different types of solvents, which are mild extraction solvents (such as distilled water), mild extraction solvents (such as ), solvents with strong extraction ability (such as ethanol, etc.). If the recommended solvents in Table 2 above are not applicable, research and demonstration materials that are not applicable should also be provided. The basis and verification data for solvent selection should be provided in the application dossiers, which should be able to verify the applicability of the selected solvents.
Question: The structure of the registered product includes the host and accessories (consumables). Now that the host has been discontinued, can I apply to change the registration to delete the host, and only keep the accessories to meet the needs of the existing host?
Answer: First, it needs to be judged according to the “Guidelines for the Division of Medical Device Registration Units”, whether the attachments retained after the host is deleted can be used as the same registration unit.
If possible, you can apply to change the registration while keeping the original cooperative use relationship unchanged, delete the host from the structural composition, and keep the attachments. At the same time, the product name needs to be modified to be consistent with the name of the accessory; the scope of application of the product needs to be modified to make it clear that it is used in conjunction with the original host model. In the technical requirements of the product, in addition to the content related to the attachments, the performance indicators related to the use of the host must also be retained.