Supramolecular organic photochemistry: incorporating function through molecular design

超分子有机光化学研究光与有机分子组成的超分子组装体的相互作用。经历光诱导过程的超分子组装体正在不断地被开发，以在诸如药物递送、催化和光电分子器件等领域中定制功能。通过超分子组装体实现的功能性是互补的分子间相互作用的结果，所述互补的分子间相互作用指导它们的形成和分子组分的光化学性质。我们正在开发创新的功能性脂质体，通过整合光致变色化合物与脂质互补性和可逆光控的元素。这些光致变色脂质体将经历膜渗透性的可逆变化，这将在包封的化合物释放后恢复膜完整性。我们将实现这一目标，通过纳入跨越整个脂质双层的光致变色剂。到目前为止，光致变色系统缺乏这方面的组织，其光诱导释放的程度一直很小，除了当脂质体稳定性不可逆地受到损害。通过跨越双层，异构化将产生可渗透的通道，捕获的分子将通过该通道扩散，导致光致变色结构的变化。带电荷的系链会将破坏性的光致变色单元锚在适当的位置，直到异构化回到它们更互补的形式，恢复局部脂质秩序。这种方法将开发通过整合脂质类似物与两个光致变色部分。这些二聚体不仅比以前的系统产生更大的膜渗透性增加，而且还恢复膜完整性。此外，我们将开发具有改进的双光子吸收的类似光致变色剂，以增强这些脂质体在实际应用中的空间和时间选择性，例如光调节药物递送，其中递送的剂量将用光精确且可逆地控制。这一战略将通过减少住院时间，带来可申请专利的技术，并为加拿大的医疗保健系统节省资金，从而使公众健康受益。

Supramolecular organic photochemistry examines the interaction of light with supramolecular assemblies composed of organic molecules. Supramolecular assemblies that undergo light-induced processes are continually being developed to custom-tailor functions in areas such as drug delivery, catalysis, and optoelectronic molecular devices. The functionality achieved by supramolecular assemblies is a consequence of complementary intermolecular interactions that direct their formation and the photochemical properties of the molecular components. We are developing innovative, functional liposomes through the integration of photochromic compounds with elements of lipid complementarity and reversible photocontrols. These photochromic liposomes will undergo reversible changes in membrane permeability that will restore membrane integrity following the release of encapsulated compounds. We will achieve this objective by incorporating photochromes that span the entire lipid bilayer. Thus far, photochromic systems have lacked this aspect of organization, and the extent of their photoinduced release has been small, except when liposome stability is irreversibly compromised. By spanning the bilayer, isomerization will produce permeable channels through which entrapped molecules will diffuse, resulting from changes in photochrome structure. Charged tethers will anchor the disruptive, photochromic units in place until isomerization back to their more complementary form restores the local lipid order. This approach will be developed through the integration of lipid analogues with two photochromic moieties. These dimers will not only produce larger increases in membrane permeability than previous systems, but also restore membrane integrity. In addition, we will develop similar photochromes with improved two-photon absorption to enhance the spatial and temporal selectivity of these liposomes in practical applications such as photoregulated drug delivery where the delivered dosage will be precisely and reversibly controlled with light. This strategy will benefit public health through a reduction in hospitalization time, lead to patentable technologies, and generate an overall savings to Canada's health care system.