Ultrathin two-dimensional covalent organic framework nanoprobe for interference-resistant two-photon fluorescence bioimaging

Abstract

A two-photon fluorescent covalent organic framework nanopore is designed for the first time for H2S interference-resistant bioimaging.

In vivo therapeutic response monitoring by a self-reporting upconverting covalent organic framework nanoplatform

“…S9 †). We suspected that the sheltering effect from the framework architecture of the COFs could effectively improve the photostability of ICG, 26 which possesses poor photostability and oen results in failure with respect to practical applications. Furthermore, we also demonstrated that the physiological pH conditions and acidic tumor microenvironment have no signicant effects on ICG breakage under 980 nm laser irradiation (Fig.…”

“…Covalent organic frameworks (COFs), entirely consisting of organic building blocks, are promising tools for biosensing and nanomedicine, owing to their diversied functionalities, large surface areas and high porosities. [26][27][28][29][30][31][32] The building blocks of COFs can themselves be designed as active parts, increasing efficiency when functionalizing the materials. 33 However, the use of porphyrin based-COF systems for in vivo applications is still hampered by the following intrinsic limitations.…”

“…Traditional solvothermal synthesis usually results in micron-level COFs. Although COF nanosheets can be obtained via the solventassisted exfoliation of bulk COFs, 26 the acquired COF nanosheet mixtures with various sizes and morphologies are difficult to isolate, inducing lower bioavailability and affecting the photodynamic efficacy. (ii) The photodynamic effects of COFs are stimulated by visible light (less than 700 nm), which can be attenuated by endogenous biomolecules (such as hemoglobin and melanin) and, therefore, has a low tissue penetration depth.…”

Tumor-acidity activated surface charge conversion of two-photon fluorescent nanoprobe for enhanced cellular uptake and targeted imaging of intracellular hydrogen peroxide

“…Another advantage of two-photon probes is the capability of imaging deep inside a tissue. [49][50][51][52] For in vivo bioimaging applications, an exact knowledge about the maximum tissue penetration depth of the nanoprobe was required. Targeted imaging of H 2 O 2 was also assessed in acidic tissues.…”

Electrochemically Facile Hydrogen Evolution Using Ruthenium Encapsulated Two Dimensional Covalent Organic Framework (2D COF)

“…The synthesis of 2D COFs has become important in recent times. The 2D COFs could be tuned structurally . The importance of these COFs lies in the fact that they show good stability and enhanced hydrogen evolution.…”