Challenges in Formulating Sunscreen Products.

Developing efficient sunscreen products with an acceptable sensory feel after application on skin, that meet current regulatory market and consumer requirements, is a major challenge, exacerbated by new restrictions limiting the use of certain ingredients previously considered crucial. This paper outlines a development strategy for -formulating sunscreens along a generic professional development pathway. Each galenic system will be different and must be customized. Development starts with benchmarking, followed by UVA/UVB filter platform selection and in silico calculation/optimization of photoprotection performance for the desired SPF, UVA-PF, and other requested endpoints. Next comes the selection of the emulsifier system and other key formulation ingredients, such as oil components, triplet quenchers, and antioxidants, with sensory, rheological, and film formation functions. Preliminary cost estimation is then performed to -complete the conceptual process before the start of the practical galenic development. The successful development of modern sunscreen products is based on -comprehensive expertise in chemistry, galenic methodology, regulation, and patenting, as well as specific -market and consumer requirements. The selection of the UV filters is the first key decision and constrains later choices. Other properties, such as water resistance and preservation or active ingredients, may need to be considered. The 4 basic requirements of efficacy, safety, registration, and patent freedom become checklist items to ensure that after development, a sunscreen product has a chance of success.

Complex polyfluoride additives in Fmoc-amino acid fluoride coupling processes. Enhanced reactivity and avoidance of stereomutation.

[reaction: see text] Isolated Fmoc amino acid fluorides have previously been shown to be among the most efficient reagents for peptide bond formation. Now, it has been found that anionic, polyhydrogen fluoride additives are capable of diverting many of the classical peptide coupling processes to acid fluoride couplings. Examples include the use of N-HBTU or N-HATU and the carbodiimide technique. As HF-containing species, these additives provide a more suitable medium for the coupling of systems that are sensitive to loss of configuration at the reactive carboxyl function.