Themed collection Most popular 2021 analytical chemistry articles, 2021

In recent years, DNA has been widely noted as a kind of material that can be used to construct building blocks for biosensing, in vivo imaging, drug development, and disease therapy because of its advantages of good biocompatibility and programmable properties.

Small-molecule based fluorescent probes are increasingly important for the detection and imaging of biological signaling molecules due to their simplicity, high selectivity and sensitivity, whilst being non-invasive, and suitable for real-time analysis of living systems.

Near-infrared fluorescent molecular probes with improved imaging depth and optimized biodistribution have been reviewed, showing great potential for diagnosis of nephro-urological diseases.

Fluorescence imaging in the second near-infrared (NIR-II, 1000–1700 nm) window has exhibited advantages of high optical resolution at deeper penetration (ca. 5–20 mm) in bio-tissues owing to the reduced photon scattering and tissue autofluorescence.

This minireview describes the development of NIR chemical probes for various protein-tag systems.

Structural and process controls of NIR-II AIEgens realize manipulating of radiative (R) and nonradiative (NR) decay for precise theranostics.

This review highlights the molecular design strategy of β-galactosidase-activatable probes from turn-on mode to ratiometric mode, from ACQ to AIE-active probes, from NIR-I to NIR-II imaging and dual-mode of chemo-fluoro-luminescence imaging.

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated (Cas) protein systems revolutionize genome engineering and advance analytical chemistry and diagnostic technology.

The recent development in phosphorescent iridium, ruthenium and rhenium complexes as theranostic anticancer agents is summarized.

The chronological evolution of small organic molecular fluorescent probes for thiols: from separation dependency analysis to cellular specific analysis, what's next?

HSA lysine-161 covalent bound quinoxaline–coumarin based fluorescent dye realized in situ blood drug concentration monitoring and tumor visualization.

We rationally designed a leucine aminopeptidase (LAP) activated fluorogenic probe hCy-CA-LAP with high hepatocyte-targeting ability for accurate and sensitive imaging of DILI.

Systematic investigation of various homoallylamines reveals N-p-methoxybenzyl homoallylamine as the optimal 2-aza-Cope reaction moiety for development of highly efficient formaldehyde fluorescent probes for in vitro and in vivo imaging.

Rather than tracking aging using the resting state, ROKS, an optical probe, was developed for evaluating the degree of aging dynamically by precisely monitoring the stress response of individuals under stress.

Acridonylalanine (Acd) is photostable, with a high quantum yield and long fluorescence lifetime in water. An evolved tRNA synthetase (RS) enables genetic incorporation of Acd in mammalian cells and its use in fluorescence lifetime imaging microscopy.

The pollutant reactive red 2 was employed to synthesize fluorescent carbon nanodots allowing biological imaging in vitro and in vivo.

In this contribution, based on a “step-by-step” molecular design strategy, a novel NIR amphiphilic AIEgen TPA-S-TPP with a triplet lifetime of 11.43 μs and surmounting the shackle of MMP was successfully fabricated for amplified tumor ablation.

A Cell Endocytosis-Activated Fluorescent (CEAF) probe triggered by disaggregation and protonation is designed for high contrast in vivo bioimaging and diagnostics in the second near-infrared window (1000–1700 nm).

A series naphthalimide-based fluorophores were designed by alkyl spacer length engineering to discover a pH-tolerant lysosomal marker. This approach also allows to probe lysosome-related organelles in C. elegans and communication between organelles.

COVID-19 glucose test: translating SARS-CoV-2 detection into a glucose test is achieved by incorporating target-responsive rolling circle amplification and a CRISPR-based collateral cleavage module with a portable glucose meter.

Ion clustering of dilute chromium species was unexpectedly revealed in a high-temperature molten chloride salt, challenging several long-held assumptions regarding specific ionic interactions and transport in molten ionic media.

A series of NIR-emissive phospha-xanthene dyes bearing an ethynyl group are reported. The late-stage functionalisation of the NIR dyes enables creation of multi-functionalised fluorescent probes that can be designed to target organelles of interest.

An AIEgen-functionalized cucurbit[7]uril was synthesized for the first time and spontaneously self-assembled into nanoaggregates in aqueous solutions and allowed subcellular imaging of the lysosome and photodynamic therapy and chemotherapy of cancer.

This study introduces a new electrochemical sensing strategy for the rapid detection of circulating tumor DNA (ctDNA) from whole blood in combination with a network of DNA-Au@MNPs with high sensitivity and excellent selectivity.

A ratiometric photoacoustic imaging probe activated by selenol was developed for visual monitoring of pathological progression of autoimmune hepatitis.

We report on a study that combines advanced fluorescence methods with molecular dynamics simulations to cover timescales from nanoseconds to milliseconds for a large protein, the chaperone Hsp90.

Fluorescent nucleoside analogue ABN is readily detected at the single-molecule level and retains a quantum yield >50% in duplex DNA oligonucleotides.

Microdroplets display distinctive interfacial chemistry, manifested as accelerated reactions relative to those observed for the same reagents in bulk.

A new type of purely organic light-harvesting PET supramolecular assembly is constructed with efficient energy transfer and ultrahigh antenna effect. Moreover, the assembly could be used for mitochondria targeted imaging in A549 cancer cells.

Small-molecule subcellular organelle-targeting theranostic probes are crucial for early disease diagnosis and treatment.