Unearthing the Real-Time Excited State Dynamics from Antenna to Rare Earth Ions Using Ultrafast Transient Absorption.

The conventional energy transfer pathway in organic lanthanide complexes is purported to be from the excited singlet state of the chromophore to the triplet state and subsequently directly to the emitting state of the trivalent lanthanide ion. In this work, we found that the energy transfer occurs from the triplet state to the nearest energy level, instead of directly to the emitting state of the lanthanide ion. The triplet decay rate for different lanthanide ions follows an energy gap law from the triplet level to the receiving level of the lanthanide ion.

Facile Peptide Macrocyclization and Multifunctionalization via Cyclen Installation.

Cyclen-peptide bioconjugates are usually prepared in multiple steps that require individual preparation and purification of the cyclic peptide and hydrophilic cyclen derivatives. An efficient strategy is discovered for peptide cyclization and functionalization toward lanthanide probe via three components intermolecular crosslinking on solid-phase peptide synthesis with high conversion yield. Multifunctionality can be conferred by introducing different modular parts or/and metal ions on the cyclen-embedded cyclopeptide.

Direct Construction of Corrole-Peptide Conjugates by Controllable Bilane Formation on Resin.

Corroles have attracted increasing research interests in recent decades owing to their unique properties over porphyrins. However, the relatively inefficient and tedious synthetic procedures of corrole building blocks with functional groups for bioconjugation hindered their bioapplications. Herein, we report a highly efficient protocol to synthesize corrole-peptide conjugates with good yields (up to 63 %) without using prepared corrole building blocks.

Versatile Synthesis of Multivalent Porphyrin-Peptide Conjugates by Direct Porphyrin Construction on Resin.

Multifunctional porphyrin-peptide conjugates with different propensities for self-assembly into various supramolecular nanoarchitectures play important roles in advanced materials and biomedical research. However, preparing prefunctionalized core porphyrins by traditional low-yielding statistical synthesis and purifying them after peptide ligation through many rounds of HPLC purification is tedious and unsustainable. Herein, we report a novel integrated solid-phase synthetic protocol for the construction of porphyrin moieties from simple aldehydes and dipyrromethanes on resin-bound peptides directly to form mono-, cis/trans-di-, and trivalent porphyrin-peptide conjugates in a highly efficient and controllable manner; moreover, only single final-stage HPLC purification of the products is needed.