Tissue Imprinting on 2D Nanoflakes-Capped Silicon Nanowires for Lipidomic Mass Spectrometry Imaging and Cancer Diagnosis

Abstract

Spatially resolved tissue lipidomics is essential for accurate intraoperative and postoperative cancer diagnosis by revealing molecular information in the tumor microenvironment. Matrix-free laser desorption ionization mass spectrometry imaging (LDI-MSI) is an emerging attractive technology for label-free visualization of metabolites distributions in biological specimens. However, the development of LDI-MSI technology that could conveniently and authentically reveal molecular distribution on tissue samples is still a challenge. Herein, we present a tissue imprinting technology by retaining tissue lipids on 2D nanoflakes-capped silicon nanowires (SiNWs) for further mass spectrometry imaging and cancer diagnosis. The 2D nanoflakes were prepared by liquid exfoliation of molybdenum disulfide (MoS2) with nitrogen-doped graphene quantum dots (NGQDs), which serve as both intercalation agent and dispersant. The obtained NGQD@MoS2 nanoflakes were then decorated on the tip of vertical SiNWs, forming a hybrid NGQD@MoS2/SiNWs nanostructure, which display excellent lipid extraction ability, enhanced LDI efficiency and molecule imaging capability. The peak number and total ion intensity of different lipids species on animal lung tissues obtained by tissue imprinting LDI-MSI on NGQD@MoS2/SiNWs were ∼4–5 times greater than those on SiNWs substrate. As a proof-of-concept demonstration, the NGQD@MoS2/SiNWs nanostructure was further applied to visualize phospholipids on sliced non small cell lung cancer (NSCLC) tissue along with the adjacent normal tissue. On the basis of selected feature lipids and machine learning algorithm, a prediction model was constructed to discriminate NSCLC tissues from the adjacent normal tissues with an accuracy of 100% for the discovery cohort and 91.7% for the independent validation cohort.

A reagentless electrochemical immunosensor for sensitive detection of carcinoembryonic antigen based on the interface with redox probe-modified electron transfer wires and effectively immobilized antibody

“…At the same time, methylene blue (MB), a commonly used cationic redox probe (p K 1 = 11.2), was used as the electrochemical probe. ( Zhang et al, 2022b ; Liu et al, 2022 ; Prado et al, 2022 ; Suo et al, 2022 ). Since the redox peaks of MB are at a negative potential, the electrochemical interference of redox small molecules (for example, ascorbic acid-AA, uric acid-UA, dopamine-DA, tryptophan, etc) in biological samples (for example, serum) can be effectively avoided because of their positive redox potentials.…”

“…In comparison with other detection strategies (for example, optical Analysis), electrochemical detection has advantages including fast detection speed, a simple instrument, easy integration, and miniaturization. ( Cui et al, 2020 ; Cui et al, 2021 ; Duan et al, 2021 ; Liu et al, 2022 ). The immobilization of redox probes on the electrode surface was investigated by detecting the electrochemical signals of MB.…”

Vertically-Ordered Mesoporous Silica Films Grown on Boron Nitride-Graphene Composite Modified Electrodes for Rapid and Sensitive Detection of Carbendazim in Real Samples

“…Porous materials have aroused growing attention in the construction of rapid and portable sensors ( Cui et al, 2020 ; Cui et al, 2021 ; Duan et al, 2021 ; Liu et al, 2022 ; Wei et al, 2022 ). Especially, vertically-ordered mesoporous silica films (VMSF) are a kind of porous material with perpendicularly ordered nanochannels and uniform pore size on a nanometer scale ( Walcarius, 2021 ; Ma et al, 2022a ).…”

Vertically-Ordered Mesoporous Silica Films for Electrochemical Detection of Hg(II) Ion in Pharmaceuticals and Soil Samples

“…Recently, porous materials as functional building blocks have been widely used for the construction of high-performance sensors, taking advantage of their ease of hybridization ( Cui et al, 2020 ; Cui et al, 2021 ; Duan et al, 2021 ; Liu et al, 2022 ), efficient enrichment ( Liang et al, 2021 ; Yan et al, 2021 ), and rapid mass transfer ( Zhou et al, 2022a ; Gong et al, 2022 ). Especially, vertically-ordered mesoporous silica films (VMSF) have been proven to be powerful preconcentration materials for electrochemical detection of metal ions, such as Cu 2+ ( Cheng et al, 2018 ; Lu et al, 2018 ), Hg 2+ ( Lu et al, 2018 ), Ag + ( Herzog et al, 2013 ), Pb 2+ ( Fernández et al, 2014 ; Cheng et al, 2018 ; Li et al, 2021 ), and Cd 2+ ( Cheng et al, 2018 ; Lu et al, 2018 ; Li et al, 2021 ).…”