Browsing by Author "Chan, Yang-Hsiang"

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Colorimetric and Fluorescent Dual-Mode Immunoassay Based on Plasmon-Enhanced Fluorescence of Polymer Dots for Detection of PSA in Whole Blood
(2019-03-13)
You, Pei-Yun
;
Li, Fang-Chu
;
Liu, Ming-Ho
;
Chan, Yang-Hsiang
;
應用化學系
Although enormous efforts have been devoted to the development of new types of fluorometric immuno-chromatographic test strip (ICTS) with improved sensitivity over the past years, it still remains a big challenge to design ICTS with colorimetric and fluorescent bimodal signal readout for rapid yet accurate detection of cancer markers in a clinic. Scientists have tried to prepare bimodal reporters by combining fluorescent dyes with metal nanomaterials, but their fluorescence was easily quenched by metal nanomaterials through surface energy transfer, making dual colorimetric and fluorometric ICTS very difficult to be achieved. As compared to conventional fluorescent probes, semiconducting polymer dots (Pdots) exhibit extraordinary fluorescence brightness and facile surface functionalization, which are very suitable to be engineered as bimodal signal reporting reagents. Here, we integrated highly fluorescent Pdots with strongly plasmonic Au nanorods to form Pdot-Au hybrid nanocomposites with dual colorimetric and fluorescent readout abilities. We further utilized these nanohybrids in ICTS for qualitatively fast screening (colorimetry) as well as quantitatively accurate determination (fluorometry) of prostate-specific antigen (PSA) within 10 min. By taking advantage of the plasmon-enhanced fluorescence of Pdots on Au nanorods, this immunoassay possesses much better detection sensitivity of 1.07 pg/mL for PSA, which is at least 2 orders of magnitude lower than that of conventional fluorometric ICTS. Moreover, the direct detection of PSA from human whole blood collected without sample pretreatment makes this Pdot-based ICTS platform promising for on-site point-of-care diagnostics.
FRET-Created Traffic Light Immunoassay Based on Polymer Dots for PSA Detection
(2020-01-07)
Yang, Yong-Quan
;
Yang, Yu-Chi
;
Liu, Ming-Ho
;
Chan, Yang-Hsiang
;
交大名義發表
There have been enormous efforts for developing the next generations of fluorometric lateral flow immunochromatographic strip (ICTS) owing to the great advances in fluorescent materials in these years. Here we developed one type of fluorometric ICTS based on ultrabright semiconducting polymer dots (Pdots) in which the traffic light-like signals were created by energy transfer depending on the target concentration. This platform was successfully applied for qualitatively rapid screening and quantitatively precise analysis of prostate-specific antigen (PSA) in 10 min from merely one drop of the whole blood sample. This FRET-created traffic light ICTS possesses excellent specificity and an outstanding detection sensitivity of 0.32 ng/mL for PSA. Moreover, we conducted proof-of-concept experiments to demonstrate its potential for multiplexed detection of cancer biomarkers at the same time in an individual test strip by taking advantage of the traffic light signals. To the best of our knowledge, it is the first model of a traffic light-like immunoassay test strip based on Pdots with multiplexing ability. These results would pave an avenue for designing the next generation of point-of-care diagnostics.
Low-toxic cycloplatinated polymer dots with rational design of acceptor comonomers for enhanced photocatalytic efficiency and stability
(2020-07-05)
Chang, Chih-Li
;
Lin, Wei-Cheng
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Jia, Chuan-Yu
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Ting, Li-Yu
;
Jayakumar, Jayachandran
By mimicking nature photosynthesis, a library of cycloplatinated polymer dots (Pdots) and pristine Pdots are presented and investigated the importance of selecting acceptor comonomers. A clear design strategy for the selection of acceptor comonomers of Pdots to achieve environmental-friendly, high efficiency, and long stability of photocatalytic reaction can be understood. The active PFTBTA-PtPy Pdots provide the excellent hydrogen evolution rates up to 7.34 +/- 0.82 mmol h(-1) g(-1) under a methanol-free solution and visible-light-driven system. MTT assay experiments confirm the use of the cycloplatinated Pdots as photocatalysts can minimize the toxicity, relative to the conventional approach that directly adding Pt into a solution system. Furthermore, the Pdots can be reactivated for hydrogen generation by the recycling process. The result proves that the use of cycloplatinated Pdots can not only enhance the HER efficiency and stability but also reduce the toxicity.
Molecular design of near-infrared fluorescent Pdots for tumor targeting: aggregation-induced emission versus anti-aggregation-caused quenching
(2019-01-07)
Tsai, Wei-Kai
;
Wang, Chun-I.
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Liao, Chia-Hsien
;
Yao, Chun-Nien
;
Kuo, Tsai-Jhen
Semiconducting polymer dots (Pdots) have recently emerged as a new type of ultrabright fluorescent probe that has been proved to be very useful for biomedical imaging. However, Pdots often suffer from serious fluorescence aggregation-caused quenching (ACQ) especially for near-infrared (NIR) fluorescent Pdots. This article compared two strategies to overcome the ACQ effect in near-infrared emissive Pdot systems: aggregation-induced emission (AIE) and anti-aggregation-caused quenching (anti-ACQ). The results show that the anti-ACQ platform outperforms the AIE system. The fluorescence quantum yield of anti-ACQ-based Pdots can be over 50% and the average per-particle brightness of the Pdots is about 5 times higher than that of the commercially available quantum dots. To help understand why the monomer conformations could greatly affect the optical properties of Pdots, molecular dynamics simulations were performed for the first time in such complicated Pdot systems. To demonstrate applications for in vivo fluorescence imaging, both microangiography imaging on living zebrafish embryos and specific tumor targeting on mice were performed. We anticipate that these studies will pave the way for the design of new highly fluorescent Pdot systems.
Semiconducting polymer dots as near-infrared fluorescent probes for bioimaging and sensing
(2019-01-01)
Tsai, Wei-Kai
;
Chan, Yang-Hsiang
;
應用化學系
;
Department of Applied Chemistry
In recent years, semiconducting polymer dots (Pdots) have emerged as a new type of ultrabright fluorescent probes, which have been proved to be very useful for biomedical imaging. Pdots possess several exceptional advantages including high fluorescence brightness, fast radiative rate, excellent photostability, and negligible cytotoxicity. Among these new types of Pdots, the near-infrared (NIR) fluorescent Pdots appear to be the most urgent and important owing to their promising deep-tissue imaging in the clinic. This mini-review highlights the recent progress in the design of NIR-emitting Pdots and their biomedical applications both in vitro and in vivo.
Ultrabright Fluorescent Polymer Dots with Thermochromic Characteristics for Full-Color Security Marking
(2019-08-14)
Yang, Jyun-Chi
;
Ho, Yu-Chieh
;
Chan, Yang-Hsiang
;
交大名義發表
;
應用化學系
Innovative and scalable security technologies are in high demand to deter increasing counterfeiting in modern society. Here, we report the first example of thermochromic-fluorescent ink based on semiconducting polymer dots (Pdots) by taking advantage of the unique optical properties of Pdots. We designed and synthesized two types of thermochromic molecules and then incorporated them with multicolor fluorescent Pdots. The resulting Pdots exhibited colorimetric and fluorescent dual-readout abilities in response to different temperatures which greatly increase the security level for anticounterfeiting applications. These multifunctional Pdots can be easily doped into flexible substrates or prepared as inks. These full-color inks can be further loaded into marker pens for handwriting or cartridges for inkjet printing with excellent signal-to-background contrast. Moreover, complex and delicate full-color images can be printed on security documents or currency for practical use. We anticipate that this first example of thermoresponsive dual-readout methodology based on Pdots will have broad use in advanced security marking technologies.