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12 pages, 5271 KiB

Open AccessArticle

Design, Synthesis, and Evaluation of Small Fluorescent Molecules with a 1,1-Dimethylnaphthalen-2-(1H)-One Core

by Zhengyang Wang, Shuting Wang, Yuexing Zhang and Mingliang Ma

Molecules 2024, 29(14), 3396; https://doi.org/10.3390/molecules29143396 - 19 Jul 2024

Viewed by 690

Abstract

A series of fluorescent molecules with 1,1-dimethylnaphthalene-2(1H)-one as the core were synthesized to overcome aggregation quenching and emit bright green fluorescence. The low molecular weight of these molecules led to them to smoothly pass through the cell membrane and penetrate deep [...] Read more.

A series of fluorescent molecules with 1,1-dimethylnaphthalene-2(1H)-one as the core were synthesized to overcome aggregation quenching and emit bright green fluorescence. The low molecular weight of these molecules led to them to smoothly pass through the cell membrane and penetrate deep into the nucleus to emit the corresponding fluorescence. Among them, NC-4-Br and NC-5-3O have good optical and in vitro properties and showed potential for use as fluorescent probes. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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19 pages, 14588 KiB

Open AccessArticle

Promising Molecular Architectures for Two-Photon Probes in the Diagnosis of α-Synuclein Aggregates

by Stefania Porcu, Riccardo Corpino, Carlo Maria Carbonaro, Pier Carlo Ricci, Attilio Vittorio Vargiu, Anna Laura Sanna, Giuseppe Sforazzini and Daniele Chiriu

Molecules 2024, 29(12), 2817; https://doi.org/10.3390/molecules29122817 - 13 Jun 2024

Viewed by 947

Abstract

The abnormal deposition of protein in the brain is the central factor in neurodegenerative disorders (NDs). These detrimental aggregates, stemming from the misfolding and subsequent irregular aggregation of α-synuclein protein, are primarily accountable for conditions such as Parkinson’s disease, Alzheimer’s disease, and dementia. [...] Read more.

The abnormal deposition of protein in the brain is the central factor in neurodegenerative disorders (NDs). These detrimental aggregates, stemming from the misfolding and subsequent irregular aggregation of α-synuclein protein, are primarily accountable for conditions such as Parkinson’s disease, Alzheimer’s disease, and dementia. Two-photon-excited (TPE) probes are a promising tool for the early-stage diagnosis of these pathologies as they provide accurate spatial resolution, minimal intrusion, and the ability for prolonged observation. To identify compounds with the potential to function as diagnostic probes using two-photon techniques, we explore three distinct categories of compounds: Hydroxyl azobenzene (AZO-OH); Dicyano-vinyl bithiophene (DCVBT); and Tetra-amino phthalocyanine (PcZnNH₂). The molecules were structurally and optically characterized using a multi-technique approach via UV-vis absorption, Raman spectroscopy, three-dimensional fluorescence mapping (PLE), time-resolved photoluminescence (TRPL), and pump and probe measurements. Furthermore, quantum chemical and molecular docking calculations were performed to provide insights into the photophysical properties of the compounds as well as to assess their affinity with the α-synuclein protein. This innovative approach seeks to enhance the accuracy of in vivo probing, contributing to early Parkinson’s disease (PD) detection and ultimately allowing for targeted intervention strategies. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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14 pages, 3866 KiB

Open AccessArticle

A NIR-Fluorochrome for Live Cell Dual Emission and Lifetime Tracking from the First Plasma Membrane Interaction to Subcellular and Extracellular Locales

by Eden Booth, Massimiliano Garre, Dan Wu, Harrison C. Daly and Donal F. O’Shea

Molecules 2024, 29(11), 2474; https://doi.org/10.3390/molecules29112474 - 24 May 2024

Viewed by 1078

Abstract

Molecular probes with the ability to differentiate between subcellular variations in acidity levels remain important for the investigation of dynamic cellular processes and functions. In this context, a series of cyclic peptide and PEG bio-conjugated dual near-infrared emissive BF₂-azadipyrromethene fluorophores with [...] Read more.

Molecular probes with the ability to differentiate between subcellular variations in acidity levels remain important for the investigation of dynamic cellular processes and functions. In this context, a series of cyclic peptide and PEG bio-conjugated dual near-infrared emissive BF₂-azadipyrromethene fluorophores with maxima emissions at 720 nm (at pH > 6) and 790 nm (at pH < 5) have been developed and their aqueous solution photophysical properties determined. Their inter-converting emissions and fluorescence lifetime characteristics were exploited to track their spatial and temporal progression from first contact with the plasma membrane to subcellular locales to their release within extracellular vesicles. A pH-dependent reversible phenolate/phenol interconversion on the fluorophore controlled the dynamic changes in dual emission responses and corresponding lifetime changes. Live-cell confocal microscopy experiments in the metastatic breast cancer cell line MDA-MB-231 confirmed the usability of the dual emissive properties for imaging over prolonged periods. All three derivatives performed as probes capable of real-time continuous imaging of fundamental cellular processes such as plasma membrane interaction, tracking endocytosis, lysosomal/large acidic vesicle accumulation, and efflux within extracellular vesicles without perturbing cellular function. Furthermore, fluorescence lifetime imaging microscopy provided valuable insights regarding fluorophore progression through intracellular microenvironments over time. Overall, the unique photophysical properties of these fluorophores show excellent potential for their use as information-rich probes. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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14 pages, 4419 KiB

Open AccessArticle

Synthesis and Application of Salicylhydrazone Probes with High Selectivity for Rapid Detection of Cu²⁺

by Tianzhu Shi, Zhengfeng Xie, Xinliang Mo, Yulong Feng, Tao Peng, Fuyong Wu, Mei Yu, Jingjing Zhao, Li Zhang and Ju Guo

Molecules 2024, 29(9), 2032; https://doi.org/10.3390/molecules29092032 - 28 Apr 2024

Cited by 4 | Viewed by 947

Abstract

Using the aldehyde amine condensation procedure and the triphenylamine group as the skeleton structure, the new triphenylamine-aromatic aldehyde-succinylhydrazone probe molecule DHBYMH was created. A newly created acylhydrazone probe was structurally characterized by mass spectrometry (MS), NMR, and infrared spectroscopy (FTIR). Fluorescence and UV [...] Read more.

Using the aldehyde amine condensation procedure and the triphenylamine group as the skeleton structure, the new triphenylamine-aromatic aldehyde-succinylhydrazone probe molecule DHBYMH was created. A newly created acylhydrazone probe was structurally characterized by mass spectrometry (MS), NMR, and infrared spectroscopy (FTIR). Fluorescence and UV spectroscopy were used to examine DHBYMH’s sensing capabilities for metal ions. Notably, DHBYMH achieved a detection limit of 1.62 × 10⁻⁷ M by demonstrating exceptional selectivity and sensitivity towards Cu²⁺ ions in an optimum sample solvent system (DMSO/H₂O, (v/v = 7/3); pH = 7.0; cysteine (Cys) concentration: 1 × 10⁻⁴ M). NMR titration, high-resolution mass spectrometry analysis, and DFT computation were used to clarify the response mechanism. Ultimately, predicated on DHBYMH’s reversible identification of Cu²⁺ ions in the presence of EDTA, a molecular logic gate was successfully designed. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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12 pages, 6913 KiB

Open AccessArticle

A “Pincer” Type of Acridine–Triazole Fluorescent Dye for Iodine Detection by Both ‘Naked-Eye’ Colorimetric and Fluorometric Modes

by Mei Yu, Lu Jiang, Lan Mou, Xi Zeng, Ruixiao Wang, Tao Peng, Fuyong Wu and Tianzhu Shi

Molecules 2024, 29(6), 1355; https://doi.org/10.3390/molecules29061355 - 19 Mar 2024

Viewed by 1213

Abstract

Iodine, primarily in the form of iodide (I⁻), is the bioavailable form for the thyroid in the human body. Both deficiency and excess intake of iodide can lead to serious health issues, such as thyroid disease. Selecting iodide ions among anions [...] Read more.

Iodine, primarily in the form of iodide (I⁻), is the bioavailable form for the thyroid in the human body. Both deficiency and excess intake of iodide can lead to serious health issues, such as thyroid disease. Selecting iodide ions among anions has been a significant challenge for decades due to interference from other anions. In this study, we designed and synthesized a new pincer-type acridine–triazole fluorescent probe (probe 1) with an acridine ring as a spacer and a triazole as a linking arm attached to two naphthol groups. This probe can selectively recognize iodide ions in a mixed solvent of THF/H₂O (v/v, 9/1), changing its color from colorless to light yellow, making it suitable for highly sensitive and selective colorimetric and fluorescent detection in water systems. We also synthesized another molecular tweezer-type acridine–triazole fluorescent probe (probe 2) that exhibits uniform detection characteristics for iodide ions in the acetonitrile system. Interestingly, compared to probe 2, probe 1 can be detected by the naked eye due to its circulation effect, providing a simple method for iodine detection. The detection limit of probe 1 is determined to be 10⁻⁸ mol·L⁻¹ by spectrometric titration and isothermal titration calorimetry measurements. The binding stoichiometry between probe 1 and iodide ions is calculated to be 1:1 by these methods, and the binding constant is 2 × 10⁵ mol·L⁻¹. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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19 pages, 11135 KiB

Open AccessArticle

A Comparative Study of New Fluorescent Anthraquinone and Benzanthrone α-Aminophosphonates: Synthesis, Spectroscopy, Toxicology, X-ray Crystallography, and Microscopy of Opisthorchis felineus

by Armands Maļeckis, Marija Cvetinska, Muza Kirjušina, Ligita Mežaraupe, Sanita Kecko, Inese Gavarāne, Vladimir Kiyan, Lyudmila Lider, Veronika Pavlova, Marina Savicka, Sergey Belyakov and Elena Kirilova

Molecules 2024, 29(5), 1143; https://doi.org/10.3390/molecules29051143 - 4 Mar 2024

Viewed by 1518

Abstract

In this research, we explore the synthesis of and characterize α-aminophosphonates derived from anthraquinone and benzanthrone, focusing on their fluorescence properties and potential applications in confocal laser scanning microscopy (CLSM). The synthesized compounds exhibit notable solvatochromic behavior, emitting fluorescence from green to red [...] Read more.

In this research, we explore the synthesis of and characterize α-aminophosphonates derived from anthraquinone and benzanthrone, focusing on their fluorescence properties and potential applications in confocal laser scanning microscopy (CLSM). The synthesized compounds exhibit notable solvatochromic behavior, emitting fluorescence from green to red across various solvents. Spectroscopic analysis, including ¹H-, ¹³C-, and ³¹P-NMR, FTIR, and mass spectrometry, confirms the chemical structures. The compounds’ toxicity is evaluated using etiolated wheat sprouts, revealing varying degrees of impact on growth and oxidative damage. Furthermore, the study introduces these α-aminophosphonates for CLSM imaging of the parasitic flatworm Opisthorchis felineus, demonstrating their potential in visualizing biological specimens. Additionally, an X-ray crystallographic study of an anthraquinone α-aminophosphonate provides valuable structural insights. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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17 pages, 23200 KiB

Open AccessArticle

A Novel Fluorescence Probe Based on Azamonardine for Detecting and Imaging Cysteine in Cells and Zebrafish with High Selectivity and Sensitivity

by Yixu Zhao, Ting Wang, Ahmed Mohammed Ali Abdulkhaleq, Zhongfu Zuo, Yongjin Peng and Xibin Zhou

Molecules 2023, 28(17), 6246; https://doi.org/10.3390/molecules28176246 - 25 Aug 2023

Viewed by 1405

Abstract

A novel fluorescent probe based on azamonardine (Aza) fluorophore was designed and synthesized for the highly selective detection of cysteine (Cys) in vivo and in vitro. After reacting with acryloyl chloride, the fluorescence of Aza is effectively quenched, resulting in the formation of [...] Read more.

A novel fluorescent probe based on azamonardine (Aza) fluorophore was designed and synthesized for the highly selective detection of cysteine (Cys) in vivo and in vitro. After reacting with acryloyl chloride, the fluorescence of Aza is effectively quenched, resulting in the formation of the Aza-acryl probe. Upon the addition of Cys, the ester bond of Aza-acryl is cleaved, releasing a new compound (Compound 1) with strong fluorescence, thereby achieving fluorescence turn-on detection of Cys. The structure of Aza-acryl was characterized using X-ray crystallography and NMR spectroscopy. Additionally, density functional theory was employed to elucidate the quenching mechanism of the acyl group on the Aza. Aza-acryl exhibits high selectivity towards Cys and distinguishes it from other biothiols such as homocysteine (Hcy) and glutathione (GSH). The mechanism of Aza-acryl for detecting Cys was investigated through HPLC, NMR spectroscopy, high-resolution mass spectrometry, and reaction kinetics experiments. Aza-acryl demonstrates excellent imaging capabilities for Cys in cells and zebrafish, providing a reliable and selectable tool for the detection and imaging of Cys in biological systems. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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13 pages, 5549 KiB

Open AccessArticle

Reversible Luminescent Switching Induced by Heat/Water Treatment in a Zero-Dimensional Hybrid Antimony(Ⅲ) Chloride

by Ying-Chen Peng, Hao-Wei Lin, Sheng-Hua Zhou, Jian-Ce Jin, Ting-Hui Zhuang, Abdusalam Ablez, Ze-Ping Wang, Ke-Zhao Du and Xiao-Ying Huang

Molecules 2023, 28(4), 1978; https://doi.org/10.3390/molecules28041978 - 19 Feb 2023

Cited by 8 | Viewed by 2641

Abstract

Recently zero-dimensional (0-D) inorganic–organic metal halides (IOMHs) have become a promising class of optoelectronic materials. Herein, we report a new photoluminescent (PL) 0-D antimony(III)-based IOMH single crystal, namely [H₂BPZ][SbCl₅]·H₂O (BPZ = benzylpiperazine). Photophysical characterizations indicate that [H [...] Read more.

Recently zero-dimensional (0-D) inorganic–organic metal halides (IOMHs) have become a promising class of optoelectronic materials. Herein, we report a new photoluminescent (PL) 0-D antimony(III)-based IOMH single crystal, namely [H₂BPZ][SbCl₅]·H₂O (BPZ = benzylpiperazine). Photophysical characterizations indicate that [H₂BPZ][SbCl₅]·H₂O exhibits singlet/triplet dual-band emission. Density functional theory (DFT) calculations suggest that [H₂BPZ][SbCl₅]·H₂O has the large energy difference between singlet and triplet states, which might induce the dual emission in this compound. Temperature-dependent PL spectra analyses suggest the soft lattice and strong electron–phonon coupling in this compound. Thermogravimetric analysis shows that the water molecules in the lattice of the title crystal could be removed by thermal treatment, giving rise to a dehydrated phase of [H₂BPZ][SbCl₅]. Interestingly, such structural transformation is accompanied by a reversible PL emission transition between red light (630 nm, dehydrated phase) and yellow light (595 nm, water-containing phase). When being exposed to an environment with 77% relative humidity, the emission color of the dehydrated phase was able to change from red to yellow within 20 s, and the red emission could be restored after reheating. The red to yellow emission switching could be achieved in acetone with water concentration as low as 0.2 vol%. The reversible PL transition phenomenon makes [H₂BPZ][SbCl₅]·H₂O a potential material for luminescent water-sensing. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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13 pages, 3016 KiB

Open AccessArticle

GSH-Activatable Aggregation-Induced Emission Cationic Lipid for Efficient Gene Delivery

by Yue-Rui Yuan, Qiang Liu, Deyu Wang, Yu-Dan Deng, Ting-Ting Du, Wen-Jing Yi and Sheng-Tao Yang

Molecules 2023, 28(4), 1645; https://doi.org/10.3390/molecules28041645 - 8 Feb 2023

Cited by 2 | Viewed by 2067

Abstract

The key to gene therapy is the design of biocompatible and efficient delivery systems. In this work, a glutathione (GSH)-activated aggregation-induced-emission (AIE) cationic amphiphilic lipid, termed QM-SS-KK, was prepared for nonviral gene delivery. QM-SS-KK was composed of a hydrophilic biocompatible lysine tripeptide headgroup, [...] Read more.

The key to gene therapy is the design of biocompatible and efficient delivery systems. In this work, a glutathione (GSH)-activated aggregation-induced-emission (AIE) cationic amphiphilic lipid, termed QM-SS-KK, was prepared for nonviral gene delivery. QM-SS-KK was composed of a hydrophilic biocompatible lysine tripeptide headgroup, a GSH-triggered disulfide linkage, and a hydrophobic AIE fluorophore QM-OH (QM: quinoline-malononitrile) tail. The peptide moiety could not only efficiently compact DNA but also well modulate the dispersion properties of QM-SS-KK, leading to the fluorescence-off state before GSH treatment. The cleavage of disulfide in QM-SS-KK by GSH generated AIE signals in situ with a tracking ability. The liposomes consisted of QM-SS-KK, and 1,2-dioleoylphosphatidylethanolamine (DOPE) (QM-SS-KK/DOPE) delivered plasmid DNAs (pDNAs) into cells with high efficiency. In particular, QM-SS-KK/DOPE had an enhanced transfection efficiency (TE) in the presence of 10% serum, which was two times higher than that of the commercial transfection agent PEI25K. These results highlighted the great potential of peptide and QM-based fluorescence AIE lipids for gene delivery applications. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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12 pages, 3932 KiB

Open AccessArticle

A Novel Near-Infrared Ytterbium Complex [Yb(DPPDA)₂](DIPEA) with Φ = 0.46% and τ_obs = 105 μs

by Guozhu Ren, Danyang Zhang, Hao Wang, Xiaofang Li, Ruiping Deng, Shihong Zhou, Long Tian and Liang Zhou

Molecules 2023, 28(4), 1632; https://doi.org/10.3390/molecules28041632 - 8 Feb 2023

Viewed by 2221

Abstract

The luminescent performances of near-infrared (NIR) lanthanide (Ln) complexes were restricted greatly by vibration quenching of X-H (X = C, N, O) oscillators, which are usually contained in ligands and solvents. Encapsulating Ln³⁺ into a cavity of coordination atoms is a feasible [...] Read more.

The luminescent performances of near-infrared (NIR) lanthanide (Ln) complexes were restricted greatly by vibration quenching of X-H (X = C, N, O) oscillators, which are usually contained in ligands and solvents. Encapsulating Ln³⁺ into a cavity of coordination atoms is a feasible method of alleviating this quenching effect. In this work, a novel ytterbium complex [Yb(DPPDA)₂](DIPEA) coordinated with 4,7-diphenyl-1,10-phenanthroline-2,9-dicarboxylic acid (DPPDA) was synthesized and characterized by FT-IR, ESI-MS and elemental analysis. Under the excitation of 335 nm light, [Yb(DPPDA)₂](DIPEA) showed two emission peaks at 975 and 1011 nm, respectively, which were assigned to the characteristic ²F_5/2 → ²F_7/2 transition of Yb³⁺. Meanwhile, this ytterbium complex exhibited a plausible absolute quantum yield of 0.46% and a luminescent lifetime of 105 μs in CD₃OD solution. In particular, its intrinsic quantum yield was calculated to be 12.5%, and this considerably high value was attributed to the near-zero solvent molecules bound to Yb³⁺ and the absence of X-H oscillators in the first coordination sphere. Based on experimental results, we further proposed that the sensitized luminescence of [Yb(DPPDA)₂](DIPEA) occurred via an internal redox mechanism instead of an energy transfer process. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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15 pages, 4973 KiB

Open AccessArticle

Dextran Fluorescent Probes Containing Sulfadiazine and Rhodamine B Groups

by Bi-Jie Bie, Xiao-Rui Zhao, Jia-Rui Yan, Xi-Jun Ke, Fan Liu and Guo-Ping Yan

Molecules 2022, 27(19), 6747; https://doi.org/10.3390/molecules27196747 - 10 Oct 2022

Cited by 5 | Viewed by 2263

Abstract

Fluorescent imaging has been expanded, as a non-invasive diagnostic modality for cancers, in recent years. Fluorescent probes in the near-infrared window can provide high sensitivity, resolution, and signal-to-noise ratio, without the use of ionizing radiation. Some fluorescent compounds with low molecular weight, such [...] Read more.

Fluorescent imaging has been expanded, as a non-invasive diagnostic modality for cancers, in recent years. Fluorescent probes in the near-infrared window can provide high sensitivity, resolution, and signal-to-noise ratio, without the use of ionizing radiation. Some fluorescent compounds with low molecular weight, such as rhodamine B (RhB) and indocyanine green (ICG), have been used in fluorescent imaging to improve imaging contrast and sensitivity; however, since these probes are excreted from the body quickly, they possess significant restrictions for imaging. To find a potential solution to this, this work investigated the synthesis and properties of novel macromolecular fluorescent compounds. Herein, water-soluble dextran fluorescent compounds (SD-Dextran-RhB) were prepared by the attachment of RhB and sulfadiazine (SD) derivatives to dextran carrier. These fluorescent compounds were then characterized through IR, ¹H NMR, ¹³C NMR, UV, GPC, and other methods. Assays of their cellular uptake and cell cytotoxicity and fluorescent imaging were also performed. Through this study, it was found that SD-Dextran-RhB is sensitive to acidic conditions and possesses low cell cytotoxicities compared to normal 293 cells and HepG2 and HeLa tumor cells. Moreover, SD-Dextran-RhB demonstrated good fluorescent imaging in HepG2 and HeLa cells. Therefore, SD-Dextran-RhB is suitable to be potentially applied as a probe in the fluorescent imaging of tumors. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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13 pages, 2602 KiB

Open AccessArticle

Partnered Excited-State Intermolecular Proton Transfer Fluorescence (P-ESIPT) Signaling for Nitrate Sensing and High-Resolution Cell-Imaging

by Pan Ma, Fuchun Gong, Hanming Zhu, You Qian, Lingzhi He, Jiaoyun Xia and Zhong Cao

Molecules 2022, 27(16), 5164; https://doi.org/10.3390/molecules27165164 - 13 Aug 2022

Cited by 6 | Viewed by 2153

Abstract

Nitrite (NO₂⁻) is a common pollutant and is widely present in the environment and in human bodies. The development of a rapid and accurate method for NO₂⁻ detection is always a very important task. Herein, we synthesized a [...] Read more.

Nitrite (NO₂⁻) is a common pollutant and is widely present in the environment and in human bodies. The development of a rapid and accurate method for NO₂⁻ detection is always a very important task. Herein, we synthesized a partnered excited-state intermolecular proton transfer (ESIPT) fluorophore using the “multi-component one pot” method, and used this as a probe (ESIPT-F) for sensing NO₂⁻. ESIPT-F exhibited bimodal emission in different solvents because of the solvent-mediated ESIPT reaction. The addition of NO₂⁻ caused an obvious change in colors and tautomeric fluorescence due to the graft of NO₂⁻ into the ESIPT-F molecules. From this basis, highly sensitive and selective analysis of NO₂⁻ was developed using tautomeric emission signaling, achieving sensitive detection of NO₂⁻ in the concentration range of 0~45 mM with a detection limit of 12.5 nM. More importantly, ESIPT-F showed the ability to anchor proteins and resulted in a recognition-driven “on-off” ESIPT process, enabling it to become a powerful tool for fluorescence imaging of proteins or protein-based subcellular organelles. MTT experimental results revealed that ESIPT-F is low cytotoxic and has good membrane permeability to cells. Thus, ESIPT-F was further employed to image the tunneling nanotube in vitro HEC-1A cells, displaying high-resolution performance. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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Review

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19 pages, 8933 KiB

Open AccessReview

A Review for In Vitro and In Vivo Detection and Imaging of Gaseous Signal Molecule Carbon Monoxide by Fluorescent Probes

by Can Xie, Kun Luo, Libin Tan, Qiaomei Yang, Xiongjie Zhao and Liyi Zhou

Molecules 2022, 27(24), 8842; https://doi.org/10.3390/molecules27248842 - 13 Dec 2022

Cited by 7 | Viewed by 2592

Abstract

Carbon monoxide (CO) is a vital endogenous gaseous transmitter molecule involved in the regulation of various physiological and pathological processes in living biosystems. In order to investigate the biological function of CO, many technologies have been developed to monitor the level of endogenous [...] Read more.

Carbon monoxide (CO) is a vital endogenous gaseous transmitter molecule involved in the regulation of various physiological and pathological processes in living biosystems. In order to investigate the biological function of CO, many technologies have been developed to monitor the level of endogenous CO in biosystems. Among them, the fluorescence detection technology based on the fluorescent probe has the advantages of high sensitivity, excellent selectivity, simple operation, especially non-invasive damage to biological samples, and the possibility of real-time in situ detection, etc., which is considered to be one of the most effective and applicable detection techniques. Therefore, in the last few years, a lot of work has been carried out on the design, synthesis and in vivo fluorescence imaging studies of CO fluorescent probes. Furthermore, using fluorescent probes to detect the changes in CO concentrations in living cells and tissues as well as in organisms has been one of the hot research topics in recent years. However, it is still a challenge to rationally design CO fluorescent probe with excellent optical performance, structural stability, low background interference, good biocompatibility, and excellent water solubility. Therefore, this review focuses on the research progress of CO fluorescent probes in the detection mechanism and biological applications in recent years. However, this popular and leading topic has rarely been summarized comprehensively to date. Thus, the research progress of CO fluorescent probes in recent years is reviewed in terms of their design concept, detection mechanism, and their biological applications. In addition, the relationship between the structure and performance of the probes was also discussed. More significantly, we hope that more excellent optical properties fluorescent probes for gaseous transmitter molecule CO detection and imaging will overcome the current problems of high biotoxicity and limited water solubility in future. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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21 pages, 8244 KiB

Open AccessReview

Fluorescent Organic Small Molecule Probes for Bioimaging and Detection Applications

by Yufei Yang, Fucheng Gao, Yandong Wang, Hui Li, Jie Zhang, Zhiwei Sun and Yanyan Jiang

Molecules 2022, 27(23), 8421; https://doi.org/10.3390/molecules27238421 - 1 Dec 2022

Cited by 43 | Viewed by 5331

Abstract

The activity levels of key substances (metal ions, reactive oxygen species, reactive nitrogen, biological small molecules, etc.) in organisms are closely related to intracellular redox reactions, disease occurrence and treatment, as well as drug absorption and distribution. Fluorescence imaging technology provides a visual [...] Read more.

The activity levels of key substances (metal ions, reactive oxygen species, reactive nitrogen, biological small molecules, etc.) in organisms are closely related to intracellular redox reactions, disease occurrence and treatment, as well as drug absorption and distribution. Fluorescence imaging technology provides a visual tool for medicine, showing great potential in the fields of molecular biology, cellular immunology and oncology. In recent years, organic fluorescent probes have attracted much attention in the bioanalytical field. Among various organic fluorescent probes, fluorescent organic small molecule probes (FOSMPs) have become a research hotspot due to their excellent physicochemical properties, such as good photostability, high spatial and temporal resolution, as well as excellent biocompatibility. FOSMPs have proved to be suitable for in vivo bioimaging and detection. On the basis of the introduction of several primary fluorescence mechanisms, the latest progress of FOSMPs in the applications of bioimaging and detection is comprehensively reviewed. Following this, the preparation and application of fluorescent organic nanoparticles (FONPs) that are designed with FOSMPs as fluorophores are overviewed. Additionally, the prospects of FOSMPs in bioimaging and detection are discussed. Full article

(This article belongs to the Special Issue Design and Preparation of Organic Fluorescent Materials for Detection and Bio-Imaging)

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