Core-crosslinked nanomicelles based on crosslinkable prodrug and surfactants for reduction responsive delivery of camptothecin and improved anticancer efficacy

Selective Perchlorate Sensing Using Electrochemical Impedance Spectroscopy with Self-Assembled Monolayers of semiaza-Bambusurils

In the last two decades, perchlorate salts have been identified as environmental pollutants and recognized as potential substances affecting human health. We describe self-assembled monolayers (SAMs) of novel semiaza-bambus[6]urils (semiaza-BUs) equipped with thioethers or disulfide (dithiolane) functionalities as surface-anchoring groups on gold electrodes. Cyclic voltammetry (CV) with Fe(CN)6 3-/4- as a redox probe, together with X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and ellipsometry, were employed to characterize the interactions at the interface between the anchoring groups and the metal substrate. Data showed that the anion receptors' packing on the gold strongly depends on the anchoring group. As a result, SAMs of BUs with lipoic amide side chains show a concentration-dependent layer thickness. The BU SAMs are extremely stable on repeated electrochemical potential scans and can selectively recognize perchlorate anions. Our electrochemical impedance spectroscopy (EIS) studies indicated that semiaza-BU equipped with the lipoic amide side chains binds perchlorate (2-100 mM) preferentially over other anions such as F- , Cl- , I- , AcO- , H2 PO4 - , HPO4 2- , SO4 2- , NO2 - , NO3 - , or CO3 2- . The resistance performance is 10 to 100 times more efficient than SAMs containing all other tested anions.

Effect of hydrophilic or hydrophobic interactions on the self-assembly behavior and micro-morphology of a collagen mimetic peptide

Abstract

Peptide self-assembles with bionic properties have been widely utilized for bioactive drugs and biomedical materials. Collagen mimetic peptide (CMP) gains more attention due to its unique advantages in biosecurity and function. Unfortunately, the self-assembly mechanism of CMP, particularly the effect of intermolecular forces on its self-assembly behavior and morphology, is still unrecognized. Herein, the hydrophilic glycidol (GCD) and hydrophobic Y-glycidyl ether oxypropyl trimethoxysilane (GLH) were grafted onto the side chains of CMP through the ring-opening reaction (GCD/CMP, GLH/CMP). Subsequently, the effects of hydrophilic and hydrophobic interactions on the self-assembly behavior and morphology of CMP were further studied. The results substantiated that the GCD/CMP and GLH/CMP self-assembly followed “nucleation-growth” mechanism, and the supererogatory hydrophilic and hydrophobic groups prolonged the nucleation and growth time of CMP self-assembly. Noted that the hydrophilic interaction had stronger driving effects than hydrophobic interaction on the self-assembly of CMP. The GCD/CMP and GLH/CMP self-assembles exhibited fibrous 3D network and microsphere morphology, respectively. Furthermore, the GLH/CMP self-assembles had better resistance to degradation. Consequently, the microtopography and degradation properties of CMP self-assembles could be controlled by the hydrophilic and hydrophobic interactions between CMP, which would further provide a way for subsequent purposeful design of biomedical materials.

Graphical abstract