Fluorescence Sensing of Glutathione Thiyl Radical by BODIPY‐Modified β‐Cyclodextrin

Abstract

Comprehensive Summary The fluorescence sensing of intracellular glutathione thiyl radical (GS•) is in great demand to seek the GS•‐related pathophysiological events. Herein, boron−dipyrromethene (BODIPY)‐modified β‐cyclodextrin was developed for high‐efficiency sensing of GS•, accompanied by a fast response time (t1/2 = 218 s), with the detection limit of 468 nmol/L. Cell experiments indicated that the BODIPY‐ modified β‐cyclodextrin could be applied to detect the GS• in live A549 cells.

Multicharged cyclodextrin supramolecular assemblies

“…[310][311][312][313] Introducing small-molecule fluorescent probes into CDs can not only provide highly efficient molecular recognition capability but also endow the fluorescent probes with excellent biocompatibility. [314][315][316][317] Pu and co-workers reported the use of real-time near-infrared fluorescence (NIRF) imaging and urinalysis for the detection of bladder cancer. 318 The authors prepared a fluorescent macromolecular reporter (CyP1) composed of a specific biomarker-reactive group sensitive to aminopeptidase N (APN), a hemicyanine-based NIRF signaling moiety, and (2-hydroxypropyl)-b-cyclodextrin (HP-b-CD) (Fig.…”

Macrocyclic Supramolecular Assemblies Based on Hyaluronic Acid and Their Biological Applications

“…In addition to directly assembling with host–guest complexes through multiple hydrogen bonding and electrostatic interactions, HA can also be modified with macrocyclic compounds (e.g., cyclodextrins (CDs), cucurbit­[ n ]­urils (CB­[ n ]­s)) or functional guest molecules (e.g., pyridinium, adamantane, and peptide) through amidation to form multifunctional biomacromolecules for further assembly. CDs are macrocyclic oligosaccharides linked by d -glucose through α-1,4-glycosidic bonds, and the commonly used CDs contain six, seven, and eight d -glucose units, which are named α-, β- and γ-CD, respectively. − Due to the different cavity volumes, CDs can encapsulate different kinds of size-matched guest molecules through hydrophobic interactions. − CB­[ n ]­s are formed by condensation of glycoluril with formaldehyde under the condition of acid catalysis and contain a robust skeleton, a hydrophobic cavity, and two identical ports filled with carbonyl groups. , The commonly used CB­[ n ]­s are CB[6], CB[7], and CB[8], which can not only provide potential inclusion sites for nonpolar molecules but also bind cationic guests via ion–dipole interactions with carbonyl groups. − In terms of the interaction between macrocycle host and functional guest, the association constant is important in the process of self-assembly and release, − which directly affects the time frame of drug release, such as a photocontrolled system for different association constants of trans- and cis- azobenzene with cyclodextrin and the stability of a formed polymer–polymer hydrogel system through multivalent interactions. − With the aid of specific macrocycle host–guest, hydrophobic, and electrostatic interactions, many functional guests can be integrated into supramolecular assemblies; the formed host–guest complexes not only endow the assemblies with a responsiveness to multiple stimuli (e.g., enzymes, light, electricity, magnetism) but also enhance the luminescence intensity of molecules and improve the loading of drugs. − On the other hand, the nanosupramolecular assembly formed with HA can also improve its biocompatibility, reduce drug toxicity and side effects, and enhance cell permeability and accumulation in tumors, which has extensive application value in biomedical research.…”

Revealing Formaldehyde Fluxes in Alzheimer's Disease Brain by an Activity‐Based Fluorescence Probe

“…By contrast, molecular probe‐based fluorescence imaging methods, featured with high sensitivity and selectivity, real‐time and noninvasive in vivo visualizing abilities, have drawn tremendous interest in biological and life sciences. [ 14‐18 ] Thanks to the rapid evolution of activity‐based sensing (ABS), [ 19‐22 ] several kinds of efficient FA‐participated reactions, such as amino/hydrazine‐FA condensation, [ 23‐26 ] FA‐induced aza‐Cope rearrangement, [ 27‐34 ] and FA‐induced spiroaminal formation, [ 35‐36 ] have been widely harnessed to construct a great body of fluorescence probes for the detection of FA in vitro and in vivo . Regrettably, to the best of our knowledge, none of these probes can satisfy the requirements for FA detection in the AD brain due to the poor blood‐brain barrier (BBB) crossing ability.…”