Rigid Microenvironment Research Articles

A biomimetic phosphor that can build a rigid microenvironment for its long-lived afterglow in aqueous medium.

Organic phosphorescent materials have great prospects for application, whose performance particularly depends on the preparation method. Inspired by nature's wisdom, we report a phosphor that can utilize monomers in its environment by polymerization to construct a rigid microenvironment under light illumination, leading to a glow-in-the-dark emulsion with a phosphorescence lifetime of 1 s in water. This phosphor can achieve active growth of the aqueous emulsion with the introduction of more monomers. In the presence of trace amounts of oxygen (which has adverse effects on both polymerization and afterglow), this phosphor can still undergo photo-induced polymerization, removing the influence of oxygen and obtaining afterglow emulsion, demonstrating its adaptability to the environment. This phosphor can also catalyze the polymerization of monomers containing yellow fluorophore, obtaining long-lifetime yellow afterglow emulsion through excited state energy transfer. We have also conducted in-depth studies on the photo-catalytic and phosphorescent properties of this phosphor in model systems. This biomimetic intelligent manufacturing provides a new approach for organic phosphorescent materials and is significant for future applications.

Near-infrared TADF-type organic afterglow materials

Because of the energy gap law, as well as the spin-forbidden nature of triplet formation and transformation, it remains formidable task to achieve efficient and long-lived organic afterglow materials with long emission wavelengths, especially in the near-infrared region, under ambient conditions. Here we incorporate TADF-type afterglow mechanism in dopant-matrix systems which features a moderate kRISC of 101-102 s−1 to harvest triplet energies, boost afterglow efficiency and maintain afterglow lifetime. Specifically, we design a series of boron difluoride curcuminoid (CurBF2) compounds to serve as luminescent dopants. Organic matrices of crystalline nature and with carbonyl groups are selected to suppress triplet quenching by their rigid microenvironment and populate triplet states via dipole effect developed in our group. The resultant dopant-matrix systems display near-infrared TADF-type organic afterglow with emission wavelength >700 nm, quantum yield around 10 % and afterglow lifetime >10 ms, which can function as deep-penetrating and background-independent bioimaging probes.

A NIR iridium(III) complex-based luminescence probe for imaging mitochondria pyruvate dehydrogenase kinase 1 in triple-negative breast cancer cells

The aberrant expression of mitochondrial pyruvate dehydrogenase kinase 1 (PDK1) is highly associated with tumorigenesis and metastasis of triple-negative breast cancer (TNBC). However, because of the dearth of highly sensitive and targetable probes for PDK1, the precise imaging of mitochondrial PDK1 in TNBC cells remains challenging. We herein describe the first near-infrared (NIR) luminescence probe for visualizing PDK1 in TNBC living cells through conjugating a PDK1 inhibitor, dichloroacetic acid (DCA), to an iridium(III) complexes. This probe retains not only the favorable optical characteristics of iridium(III) complexes, but also the specific binding ability of DCA for PDK1. The probe can sensitively and specifically detect mitochondria PDK1 in TNBC cells, as verified by cellular thermal shift assay (CETSA), knockdown and selectivity experiments. Moreover, complex 1 has the capability for imaging TNBC spheroids and zebrafish models with good imaging contrast and penetration, presumably benefiting from its PDK1 target ability and NIR property. Importantly, the probe shows negligible luminescence in normal cell lines with low expression of PDK1, demonstrating its ability to discriminate TNBC cells from normal cells. This probe, which acts through the interplay of both low oxygen diffusion and a rigid microenvironment upon binding to PDK1, could provide mechanistic insights into the biological roles of PDK1 in TNBC and support the development of PDK1-based TNBC diagnostic probes in vivo.

Circularly Polarized Room Temperature Phosphorescence through Twisting‐Induced Helical Structures from Polyvinyl Alcohol‐Based Fibers Containing Hydrogen‐Bonded Dyes

AbstractRoom temperature phosphorescence (RTP) materials have garnered significant attention owing to its distinctive optical characteristics and broad range of potential applications. However, the challenge remains in producing RTP materials with more simplicity, versatility, and practicality on a large scale, particularly in achieving chiral signals within a single system. Herein, we show that a straightforward and effective combination of wet spinning and twisting technique enables continuously fabricating RTP fibers with twisting‐induced helical chirality. By leveraging the hydrogen bonding interactions between polyvinyl alcohol (PVA) and quinoline derivatives, along with the rigid microenvironment provided by PVA chains, typically, Q‐NH2@PVA fiber demonstrates outstanding phosphorescent characteristics with RTP lifetime of 1.08 s and phosphorescence quantum yield of 24.6 %, and the improved tensile strength being 1.7 times than pure PVA fiber (172±5.82 vs 100±5.65 MPa). Impressively, the transformation from RTP to circularly polarized room temperature phosphorescence (CP‐RTP) is readily achieved by imparting left‐ or right‐hand helical structure through simply twisting, enabling large‐scale production of chiral Q‐NH2@PVA fiber with dissymmetry factor of 10−2. Besides, an array of displays and encryption patterns are crafted by weaving or seaming to exemplify the promising applications of these PVA‐based fibers with outstanding adaptivity in cutting‐edge anti‐counterfeiting technology.

Circularly Polarized Room Temperature Phosphorescence through Twisting-Induced Helical Structures from Polyvinyl Alcohol-Based Fibers Containing Hydrogen-Bonded Dyes.

Room temperature phosphorescence (RTP) materials have garnered significant attention owing to its distinctive optical characteristics and broad range of potential applications. However, the challenge remains in producing RTP materials with more simplicity, versatility, and practicality on a large scale, particularly in achieving chiral signals within a single system. Herein, we show that a straightforward and effective combination of wet spinning and twisting technique enables continuously fabricating RTP fibers with twisting-induced helical chirality. By leveraging the hydrogen bonding interactions between polyvinyl alcohol (PVA) and quinoline derivatives, along with the rigid microenvironment provided by PVA chains, typically, Q-NH2@PVA fiber demonstrates outstanding phosphorescent characteristics with RTP lifetime of 1.08 s and phosphorescence quantum yield of 24.6 %, and the improved tensile strength being 1.7 times than pure PVA fiber (172±5.82 vs 100±5.65 MPa). Impressively, the transformation from RTP to circularly polarized room temperature phosphorescence (CP-RTP) is readily achieved by imparting left- or right-hand helical structure through simply twisting, enabling large-scale production of chiral Q-NH2@PVA fiber with dissymmetry factor of 10-2. Besides, an array of displays and encryption patterns are crafted by weaving or seaming to exemplify the promising applications of these PVA-based fibers with outstanding adaptivity in cutting-edge anti-counterfeiting technology.

Narrow-Band Deep-Blue Emission and Superior Thermal Stability of Fluoroaluminate Phosphor Based on Tungsten Bronze-Type Mineral Structure.

Screening novel narrow-band phosphors inspired by natural mineral structures is urgently demanded for improving the performance of phosphor-converted light-emitting diodes. In this work, a novel narrow-band deep-blue-emitting tungsten bronze-type KCaAl2F9:Eu2+ phosphor with superior thermal stability is successfully synthesized. Structural analysis shows that the representative KCaAl2F9:0.013Eu2+ phosphor crystallizes in an orthorhombic space group C2221 with a rigid network. The rigid [AlF6]3- octahedrons are linked together by sharing corners to build endless [AlF6]3-∞ chains, further stacking with each other in a highly cross-linked way to establish the rigid network of the KCaAl2F9 host. Benefiting from the rigid microenvironment, the developed phosphor not only shows a narrow-band deep-blue emission with a full width at half maximum of 45 nm and a high color purity of 92%, but it also exhibits the superior thermal stability with an emission loss of only 10% at 423 K, demonstrating its application potential in bridging the deep-blue spectral cavity toward sunlight-like full-spectrum lighting. In addition, the concentration/temperature quenching behaviors of KCaAl2F9:Eu2+ phosphor are systematically investigated. By revealing the specific structure-property relationship of tungsten bronze-type KCaAl2F9:Eu2+ phosphor, the present study provides a significant guide for identifying the novel narrow-band deep-blue-emitting component applicable to full-spectrum warm white light-emitting diode devices.

Macroscopic Assembly of Chiral Hydrogen-bonded Metal-free Supramolecular Glasses for Enhanced Color-tunable Ultralong Room Temperature Phosphorescence.

Glassy materials, with desirable mechanical rigidity, shaping ability, high transparency, are attracting great interest in diverse fields. However, optically bulk molecule-based glasses are still rare, mainly due to limited monomeric species and harsh preparation conditions. Herein, we report a facile bottom-up solution fabrication process to obtain metal-free supramolecular glasses (SMGs) at the macroscopic scale using L-Histidine and hexamethylenetetramine as building blocks. The chiral SMGs possess color-tunable ultralong room temperature phosphorescence (decay lifetime up to 141.2 ms) and circular polarized luminescence (g factor up to 8.7×10-3 ). The strong hydrogen bonds effectively drive the formation of SMGs, and provide a rigid microenvironment to boost triplet exciton generation. By virtue of excitation- and temperature-dependent ultralong phosphorescence of the SMGs, applications including multicolored displays, visual UV detection, and persistently luminescent thermometer are demonstrated.

Macroscopic Assembly of Chiral Hydrogen‐bonded Metal‐free Supramolecular Glasses for Enhanced Color‐tunable Ultralong Room Temperature Phosphorescence

AbstractGlassy materials, with desirable mechanical rigidity, shaping ability, high transparency, are attracting great interest in diverse fields. However, optically bulk molecule‐based glasses are still rare, mainly due to limited monomeric species and harsh preparation conditions. Herein, we report a facile bottom‐up solution fabrication process to obtain metal‐free supramolecular glasses (SMGs) at the macroscopic scale using L‐Histidine and hexamethylenetetramine as building blocks. The chiral SMGs possess color‐tunable ultralong room temperature phosphorescence (decay lifetime up to 141.2 ms) and circular polarized luminescence (g factor up to 8.7×10−3). The strong hydrogen bonds effectively drive the formation of SMGs, and provide a rigid microenvironment to boost triplet exciton generation. By virtue of excitation‐ and temperature‐dependent ultralong phosphorescence of the SMGs, applications including multicolored displays, visual UV detection, and persistently luminescent thermometer are demonstrated.

Red Room‐Temperature Afterglow Emissions of Polymer‐Based Doped Materials by Phosphorescence Förster‐Resonance Energy Transfer

AbstractA newly emerged and attractive strategy to obtain afterglow is the use of the Förster‐resonance energy transfer (FRET) from an energy donor with room‐temperature phosphorescence (RTP) to an energy acceptor with fluorescence. Due to the transfer of energy between molecules with different emissions, it is possible to develop the ultralong and long‐wavelength afterglow materials. However, there are few reports on red afterglow materials with emission wavelengths up to 650 nm because of the difficulty of accurate design of chemical structures. Herein, a series of red afterglow materials with emission wavelengths of 650 nm are constructed using polyvinylpyrrolidone as the host, multisubstituted isoquinolines as the guests, and triphenylamine‐based dicyanomethylene‐4H‐pyran derivative as the energy acceptor. Two‐component host‐guest materials exhibit yellow‐green, yellow, and orange RTP with delayed lifetimes of 205‐301 ms and phosphorescence quantum yields of 5.3‐13.2%, which originate from the guests in a rigid microenvironment provided by the host polymer. Three‐component doped materials exhibit red afterglow with a delayed lifetime of 11‐83 ms and an emission quantum yield of 16.2‐22.1%, which is determined to be delayed fluorescence caused by triplet‐to‐singlet FRET from isoquinolines to dicyanomethylene‐4H‐pyran derivative. This work provides inspiration for the development of doped materials with long‐wavelength room‐temperature afterglow.

Manipulation of Organic Afterglow in Fluoranthene-Containing Dopant-Matrix Systems: From Conventional Room-Temperature Phosphorescence to Efficient Red TADF-Type Organic Afterglow.

It remains challenging to fabricate highly-efficient and long-lived organic afterglow materials, especially in the case of red afterglow systems. Here we develop advanced charge transfer (CT) technology to boost afterglow efficiency and lifetimes in fluoranthene-containing dopant-matrix systems. First, organic CT molecules possess singlet-triplet splitting energy (ΔEST ) of around 0.5 eV, much smaller than localized excitation systems. Second, upon doping into suitable organic matrices, dipole-dipole interactions between 1 CT states and organic matrices reduce 1 CT levels with less effect on 3 CT levels, and thus further narrow ΔEST and enhance intersystem crossing. Third, the rigid planar structure of fluoranthene groups and the rigid microenvironment provided by organic matrices can suppress phosphorescence quenching. Forth, the multiple donor design enables spectral red-shifts to red region and switches on TADF mechanism to improve afterglow efficiency to 13.1 % and maintain afterglow lifetime of 0.1 s. Such high-performance afterglow materials have been rarely explored in reported studies.

Supramolecular modulation in photophysical features of berberine and its application towards ATP sensing

In this study we report supramolecular interaction of the cationic dye berberine (BBR) with the highly substituted polyanionic cyclodextrin derivative, sulfobutylether beta cyclodextrin (SBE10βCD). Though interaction of BBR with parent β-cyclodextrin (βCD) host is very weak, its interaction with SBE10βCD host is significantly strong with an association constant Ka as large as ∼2.67 × 105 M−1. Strong binding of BBR with SBE10βCD is governed by cooperative effect of electrostatic attraction and enhanced hydrophobic interaction caused by extended SBE10βCD cavity for bound BBR dye. In the BBR-SBE10βCD complex, lower micropolarity and rigid microenvironment of host cavity cause a large decrease both in structural agility and intramolecular charge transfer (ICT) state formation of bound BBR. Accordingly, the non-radiative de-excitation of excited BBR in the dye-host complex is reduced significantly, causing its emission intensity to increase quite largely. The BBR-SBE10βCD complex is found to be highly sensitive towards ionic strength of the medium. This property is further explored to form a ternary complex, BBR-SBE10βCD-Cd2+, with largely reduced fluorescence intensity. Interestingly, this ternary complex exhibits selective fluorescence turn-on in response to an important bio-analyte, adenosine triphosphate (ATP). Present study, thus, demonstrates a very strong supramolecular complex, BBR-SBE10βCD, which is found to be very useful in the ATP detection in the presence of Cd2+, involving the ATP responsive fluorescence.

Highly tunable ultralong room-temperature phosphorescence from ionic supramolecular adhesives for multifunctional applications

• This is the first example of supramolecular adhesives with long-afterglow property. • The solvent molecules act as comonomers to promote the formation of adhesives. • The adhesives show high adhesion ability to glass and tile up to 2.86 MPa. • Smart applications are demonstrated by integrating adhesion and afterglow properties. Molecular Room-temperature phosphorescent (RTP) materials with ultralong-lived excited states have attracted extensive attention in both academia and industry. However, the soft and flexible RTP materials with facile processability are still very limited. In this work, we report the first example of supramolecular adhesives (SAs) with tunable ultralong RTP lifetime as high as 638.9 ms, based on the self-assembly of low-molecular-weight sodium m-carboxyphenylborate and solvent molecules. Interestingly, the fabricated SAs show strong adhesion performance to various substrates, especially for glass and tile. Both experimental and theoretical studies indicate that multiple intermolecular interactions (such as hydrogen-bonding, π - π interaction, and electrostatic force) efficiently promote the formation of cross-linked network structure, which helps to construct a rigid microenvironment to boost the RTP emission. Moreover, multifunctional applications including product labeling, positioning adhesion, encryption, and decoration are well-demonstrated by integrating the strong adhesion and long-afterglow properties. Therefore, this work provides an effective strategy to design and synthesize novel SAs with ultralong RTP by combining low-molecular-weight phosphors and readily available solvents, which have great practical application prospects in information safety and anti-counterfeiting fields.

Polyacrylamide-Based Binary Luminescent Copolymer Materials Exhibit Color-Tunable and Efficient Long-Lived Room Temperature Phosphorescence.

Polymer-based pure organic room temperature phosphorescence (RTP) materials have garnered considerable interest, among which RTP systems with prolonged lifetimes and tunable emission colors are promising for applications in sensing, flexible electronics, bioassay, anti-counterfeiting, and data encryption. Herein, facile doping method is reported based on two types of copolymers with benzene/biphenyl-based light-emitting cores as their side chains, whereby the two copolymers are robustly crosslinked via noncovalent interactions including hydrogen bonding and halogen bonding that occur between the light-emitting cores and polyacrylamide backbones. Persistent RTP emission with prolonged lifetime up to 1.9 s and phosphorescence quantum yield as high as 40.1% are obtained in single copolymers, attributed to the conformation restriction of phosphorescent dyes originating from the rigid microenvironment. Furthermore, multicolor phosphorescence signals are observed in the doped binary luminescent copolymer systems that can be effectively regulated by the feed ratio of luminescent cores and irradiation wavelengths. Possible mechanisms for this efficient and long-lived color-tunable RTP system are discussed on the basis of the experimental data and theoretical calculations. In addition, it is also demonstrated that the color-tunable RTP emission of the doped copolymer systems under ambient conditions allows for further exploitation in the application of dynamic information encryption.

Pancreatic Adenocarcinoma Therapeutics Targeting RTK and TGF Beta Receptor.

Despite the improved overall survival rates in most cancers, pancreatic cancer remains one of the deadliest cancers in this decade. The rigid microenvironment, which majorly comprises cancer-associated fibroblasts (CAFs), plays an important role in the obstruction of pancreatic cancer therapy. To overcome this predicament, the signaling of receptor tyrosine kinases (RTKs) and TGF beta receptor (TGFβR) in both pancreatic cancer cell and supporting CAF should be considered as the therapeutic target. The activation of receptors has been reported to be aberrant to cell cycle regulation, and signal transduction pathways, such as growth-factor induced proliferation, and can also influence the apoptotic sensitivity of tumor cells. In this article, the regulation of RTKs/TGFβR between pancreatic ductal adenocarcinoma (PDAC) and CAFs, as well as the RTKs/TGFβR inhibitor-based clinical trials on pancreatic cancer are reviewed.

Exonuclease I-assisted fluorescence aptasensor for tetrodotoxin.

A fluorescence aptasensor for the highly specific and sensitive determination of tetrodotoxin was established with tetrodotoxin-aptamer as the recognition unit, berberine as the signal reporter and exonuclease I as the elimination agent for the background. Berberine has a weak fluorescence emission at 540nm, and it can form the tetrodotoxin-aptamer/berberine complex, resulted in an increased fluorescence. After introducing exonuclease I, it can degrade the single strand oligonucleotides of tetrodotoxin-aptamer into the single nucleotide in the absence of tetrodotoxin, which lead to dramatic fluorescence quenching, and reduce the background signal of sensing system. Once tetrodotoxin is in the presence, tetrodotoxin-aptamer is converted into the stable neck ring conformation, which resists the degradation of exonuclease I and provides a more rigid micro-environment for the excited state of berberine, and then the strong fluorescence is observed. Based on the above properties, an ultrasensitive label-free fluorescence aptasensor for tetrodotoxin is established. The fluorescence aptasensor shows good analytical performance with the linear increase of fluorescence intensity at the tetrodotoxin concentration from 0.030nM to 6.0×103nM. The detection limit of 11.0 pM is much lower than that of other reported sensor methods.

Enhanced oxygen sensing sensitivity by eliminating the protection of triplet phosphorescence.

High oxygen sensitivity (the slope of the Stern-Volmer plot reaches 0.73/μM) is achieved with a phosphorescence indicator, gadolinium-hematoporphyrin monomethyl ether (Gd-HMME), by decreasing the extent of its protection. In air-saturated solution, the phosphorescence quantum efficiency (QE) of Gd-HMME in a non-rigid microenvironment is lower than that in a rigid microenvironment. In contrast, when oxygen is removed, the QE of Gd-HMME in the non-rigid microenvironment was found to be same as that of Gd-HMME in the rigid microenvironment. This indicates that Gd-HMME is much more sensitive to oxygen in the non-rigid microenvironment. The oxygen sensitivity of Gd-HMME was found to increase as the rigidity of its microenvironment decreases. The oxygen response of Gd-HMME without any protection reaches 240 (0-374 μM oxygen), whereas that in the rigid microenvironment is only 3 in this range. The measurement precision of Gd-HMME without any protection is lower than that in the rigid microenvironment. These results indicate that the measurement of oxygen in different concentration ranges would require the rigidity of the microenvironment to be varied. Gd-HMME without any protection can be applied to detect oxygen as low as 0.1 μM. The detection limit of oxygen was evaluated to be as low as 20 nM based on Gd-HMME without any protection.

Modulation of Fluorescent Protein Chromophores To Detect Protein Aggregation with Turn-On Fluorescence.

We present a fluorogenic method to visualize misfolding and aggregation of a specific protein-of-interest in live cells using structurally modulated fluorescent protein chromophores. Combining photophysical analysis, X-ray crystallography, and theoretical calculation, we show that fluorescence is triggered by inhibition of twisted-intramolecular charge transfer of these fluorophores in the rigid microenvironment of viscous solvent or protein aggregates. Bioorthogonal conjugation of the fluorophore to Halo-tag fused protein-of-interests allows for fluorogenic detection of both misfolded and aggregated species in live cells. Unlike other methods, our method is capable of detecting previously invisible misfolded soluble proteins. This work provides the first application of fluorescent protein chromophores to detect protein conformational collapse in live cells.

Modulation of Fluorescent Protein Chromophore to Detect Protein Aggregation

While green fluorescent protein (GFP) has countless applications in biology, the utilization of its chromophore outside the protein is rarely reported for other purposes, possibly due to its extremely low fluorescence. Herein, we structurally modulated FP chromophore to selectively report on the misfolding and aggregation of a protein-of-interest (POI) in both purified in vitro systems and live cells. These fluorophores remain non-fluorescent after conjugating to a folded POI, and emit fluorescence quantitatively in the misfolded and aggregated POI. The excitation and emission wavelengths are well aligned with common laser sources and filters for microscopic detections. We demonstrated their capability of detecting the aggregation of purified proteins in in vitro assays and Halo-tagged pathogenic proteins in mammalian cell lines. Our work not only provides the first fluorogenic tool to detect protein aggregation, but also opens a new avenue for fluorescent protein chromophore mimics. Support or Funding Information This work was supported by the Burroughs Wellcome Fund Career Award at the Scientific Interface, Paul Berg Early Career Professorship, Lloyd and Dottie Huck Early Career Award. (a) Structural modulations of the chromophore in green fluorescent protein (HBI) to detect protein misfolding and aggregation. The fluorogenicity originates from restriction of non-radiative bond rotations in the non-polar and rigid micro-environment of misfolded and aggregated proteins. (b) Concept of using FP mimics to detect a protein-of-interest's misfolding and aggregation both in vitro and in vivo. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effects of matrix stiffness on epithelial to mesenchymal transition-like processes of endometrial epithelial cells: Implications for the pathogenesis of endometriosis

Endometriosis is defined as the presence of endometrial glands and stroma within extrauterine sites. Our previous study revealed an epithelial to mesenchymal transition (EMT)-like process in red peritoneal endometriosis, whereas membrane localization of E-cadherin was well maintained in epithelial cells of deep infiltrating endometriosis (DIE). Here we show that endometrial epithelial cells (EEE) grown on polyacrylamide gel substrates (PGS) of 2 kilopascal (kPa), a soft matrix, initiate a partial EMT-like process with transforming growth factor-β1 (TGF-β1) stimulation. Increasing matrix stiffness with TGF-β1 stimulation reduced the number of cell-cell contacts. Cells that retained cell-cell contacts showed decreased expression of E-cadherin and zonula occludens 1 (ZO-1) to cell-cell junctions. Few deep endometriotic epithelial cells (DEE) grown on 30-kPa PGS, which may mimic in vivo tissue compliance of DIE, retained localization of E-cadherin to cell-cell junctions with TGF-β1 treatment. Immunohistochemical analysis showed no phosphorylated Smad 2/3 nuclear localization in E-cadherin+ epithelial cells of DIE. We hypothesize that EEE may undergo an EMT-like process after attachment of endometrium to peritoneum in a TGF-β1–rich microenvironment. However, TGF-β1 signaling may be absent in DIE, resulting in a more epithelial cell-like phenotype in a rigid microenvironment.

RETRACTED: Polymer immobilization effect on restricting excited state structural distortion: Preparation and characterization of electrospinning fibers doped with a [Cu(N-N)(P-P)] complex

Abstract This effort was devoted to a diamine ligand derived from an electron-pulling oxadiazole. With PPh 3 as an auxiliary ligand of steric hindrance, corresponding Cu(I) complex was prepared. Its single crystal structure, electronic structure and photophysical parameters were analyzed and discussed in detail. It was found that this complex took a distorted tetrahedral coordination structure which suffered from structural distortion badly. To limit its structural distortion and thus improve its emissive performance, this complex was doped into a polymer host (PVP) through electrospinning method. Polymer immobilization effect on restricting excited state structural distortion was confirmed by a systematical comparison between solid sample, bulk sample and polymer-doped fibrous samples. This polymer framework offered a rigid and protective microenvironment for dopant molecules so that their structural distortion in excited state could be restricted, showing improved photophysical performance such as emission blue shift, long emissive lifetime and better photostability.