What is the Chemical Fluorescence Probe?
Chemical fluorescent probes are chemical instruments that are most commonly used to label antigens or antibodies in fluorescent immunoassays. They can also be used to detect microscopic properties of microenvironments, such as surfactant micelles, bimolecular membranes, and protein active sites. Chemical fluorescent probes have characteristic fluorescence in the ultraviolet-visible-near-infrared region, and their fluorescence properties (excitation and emission wavelengths, intensity, lifetime, polarization, etc.) can change with the nature of the environment. Chemical fluorescent probes include organic reagents or metal chelates. The probe is usually required to have a large molar absorption coefficient and a high fluorescence quantum yield; the fluorescence emission wavelength is long and has a large Stokes shift; when used in immunoassays, the binding to antigens or antibodies should not affect their activity.
What are the Composition and Function of Chemical Fluorescent Probes?
1. Receptor: Selectively binds to the object (substance to be tested) and causes changes in the chemical or biological microenvironment in which the probe is located.
2. Fluorophore: Converts changes in the chemical or biological microenvironment caused by the binding of the recognition group to the analyte into signals that are easily perceptible by humans (color changes) or easily detected by instruments (fluorescence, etc.). Small molecule fluorescent probes generally use organic small molecule fluorophores, common ones include: anthracene, coumarin, fluorescein, BODIPY, naphthalimide, rhodamine, and cyanine, etc. The emission wavelength range of their derivatives covers almost all visible light regions (400-800 nm). By appropriately modifying these fluorophores, coverage from blue and green light to red and near-infrared light (650-900 nm) can be achieved. . In addition, luminescent quantum dots, upconversion nanomaterials, polymer fluorescent materials, fluorescent proteins, etc. can also be used as signaling groups in fluorescent probes.
3. Spacer: Connect fluorophores and recognition groups to effectively convert recognition information into fluorescence signals (such as changes in fluorescence intensity, shifts in fluorescence spectrum, changes in fluorescence lifetime, etc.), thereby achieving effective detection of the analyte.
What is the Design Mechanism of Fluorescent Probes?
Traditional molecular probe design principles include photoinduced electron transfer (PET), intramolecular charge transfer (ICT), twisted intramolecular charge transfer (TICT), metal to ligand charge transfer (MLCT)，electron energy transfer (EET), fluorescence resonance energy transfer (FRET), excited-stateIntramolecular proton transfer (ESIPT), and excimer/exciplex formation. Emerging mechanisms include aggregation induced emission (AIE), upconversion luminescence (UCL).
What are the Applications of Fluorescent Probes?
In the field of life sciences, fluorescent probes can be used to detect various biological molecules in cells, such as DNA, RNA, proteins, etc. In the field of environmental monitoring, fluorescent probes can be used to detect various substances in water, such as heavy metal ions, organic substances, inorganic substances, etc. In the industrial field, fluorescent probes can be used to detect various chemical substances, such as organic substances, inorganic substances, catalysts, etc. In the medical field, fluorescent probes can be used to detect diseases, such as cancer, viral infections, etc.
