Fluorescent turn-on detection of cysteine using a molecularly imprinted polyacrylate linked to allylthiol-capped CdTe quantum dots

AbstractCdTe quantum dots capped with thioglycolic acid (TGA) display a strong turn-on fluorescence response if exposed to solutions of cysteine (Cys). In order to exploit this effect, a molecularly imprinted polymer (MIP) for Cys was covalently linked to the QDs via allyl mercaptan. The resulting nanomaterials (QDs, MIP-coated QDs, and nonimprint-coated QDs) were characterized by FTIR and scanning electron microscopy. The adsorption of Cys was studied in phosphate buffer (pH 7.4) with respect to equilibration times (5, 15, and 40 min, respectively), binding constants [2.98, 2.42, and 0.96 (×104 M−1)], and Langmuir isotherms (R2 = 0.9995, 0.9999, and 0.9983) in the Cys concentration range between 3.33 μM to 500 μM. The method has a detection limit of 0.85 μM (3σ, blank, for n = 10). The selectivity of the MIP-coated QDs for Cys over 19 other amino acids is similar to that of bare QDs, but MIP-QDs afford better recoveries of Cys from solutions also containing bovine serum albumin (90 %) and fetal bovine serum (97 %), respectively, when compared to the recoveries that are obtained with bare (non-imprinted) QDs (135 % and 120 %). This is probably due to the fact that the outer MIP shell largely reduces protein wrapping, dot aggregation, and matrix inclusion. FigureUsing the turn-on fluorescence detection of cysteine template, quantum dots (QDs) conjugated with MIP via allyl mercaptan were synthesized in a one-pot polymerization and exhibited a higher binding selectivity in the presence of serum matrices compared to bare QDs and non-imprinted polymer-QDs.

[1]  Cuiping Han,et al.  Synthesis of cadmium selenide quantum dots modified with thiourea type ligands as fluorescent probes for iodide ions , 2008 .

[2]  Yunsheng Xia,et al.  Fluorescence-detecting cationic surfactants using luminescent CdTe quantum dots as probes , 2007, Analytical and bioanalytical chemistry.

[3]  Chin I Lin,et al.  Molecularly imprinted polymeric film on semiconductor nanoparticles analyte detection by quantum dot photoluminescence. , 2004, Journal of chromatography. A.

[4]  Adil Denizli,et al.  Quantum dot nanocrystals having guanosine imprinted nanoshell for DNA recognition. , 2008, Talanta.

[5]  A. Abad‐Fuentes,et al.  Applications of quantum dots as probes in immunosensing of small-sized analytes. , 2013, Biosensors & bioelectronics.

[6]  Yingxin Ma,et al.  Correction to Composite QDs@MIP Nanospheres for Specific Recognition and Direct Fluorescent Quantification of Pesticides in Aqueous Media , 2012 .

[7]  Shubhra Gangopadhyay,et al.  Detection of nitroaromatic explosives using a fluorescent-labeled imprinted polymer. , 2010, Analytical chemistry.

[8]  Hongyuan Chen,et al.  CdSe/ZnS quantum dot-Cytochrome c bioconjugates for selective intracellular O2˙⁻ sensing. , 2011, Chemical communications.

[9]  Yanchun Zhao,et al.  A one-step selective fluorescence turn-on detection of cysteine and homocysteine based on a facile CdTe/CdS quantum dots-phenanthroline system. , 2013, Analytica chimica acta.

[10]  Xiu‐Ping Yan,et al.  Surface molecular imprinting on Mn-doped ZnS quantum dots for room-temperature phosphorescence optosensing of pentachlorophenol in water. , 2009, Analytical chemistry.

[11]  M. C. Morant-Miñana,et al.  Quantum dot/cyclodextrin supramolecular systems based on efficient molecular recognition and their use for sensing. , 2012, Chemical communications.

[12]  M. S. Miranda,et al.  Thiolated DAB dendrimers and CdSe quantum dots nanocomposites for Cd(II) or Pb(II) sensing. , 2012, Talanta.

[13]  Chunwei Yuan,et al.  CdTe nanocrystals as luminescent probes for detecting ATP, folic acid and l-cysteine in aqueous solution , 2009 .

[14]  T. Nyokong,et al.  A Comparative Study on the Sensitive Detection of Hydroxyl Radical Using Thiol-capped CdTe and CdTe/ZnS Quantum Dots , 2012, Journal of Fluorescence.

[15]  Yuming Dong,et al.  Ultrasensitive cysteine sensing using citrate-capped CdS quantum dots. , 2011, Talanta.

[16]  Mei-Hwa Lee,et al.  Optical recognition of salivary proteins by use of molecularly imprinted poly(ethylene-co-vinyl alcohol)/quantum dot composite nanoparticles , 2010, Analytical and bioanalytical chemistry.

[17]  Arunkumar Kathiravan,et al.  Investigation on the Photoinduced Interaction Between Water Soluble CdTe Quantum Dots and Certain Antioxidants , 2011 .

[18]  Liguang Xu,et al.  Recent developments in analytical applications of quantum dots , 2011 .

[19]  Fangfang Liu,et al.  A novel dual-function molecularly imprinted polymer on CdTe/ZnS quantum dots for highly selective and sensitive determination of ractopamine. , 2013, Analytica chimica acta.

[20]  Igor L. Medintz,et al.  Active cellular sensing with quantum dots: transitioning from research tool to reality; a review. , 2012, Analytica chimica acta.

[21]  Jing Liu,et al.  A simple and sensitive method for L-cysteine detection based on the fluorescence intensity increment of quantum dots. , 2009, Analytica chimica acta.

[22]  Yingxin Ma,et al.  Composite QDs@MIP nanospheres for specific recognition and direct fluorescent quantification of pesticides in aqueous media. , 2012, Analytical chemistry.

[23]  Ricardas Rotomskis,et al.  Interaction of Water-Soluble CdTe Quantum Dots with Bovine Serum Albumin , 2010, Nanoscale research letters.

[24]  W. Tan,et al.  Aptamer-conjugated optical nanomaterials for bioanalysis , 2012 .

[25]  Angel Orte,et al.  Fluorescent nanoparticles for intracellular sensing: a review. , 2012, Analytica chimica acta.

[26]  Z. Rosenzweig,et al.  Luminescent CdS quantum dots as selective ion probes. , 2002, Analytical chemistry.

[27]  Highly sensitive detection of lead(II) ion using multicolor CdTe quantum dots , 2011, Microchimica Acta.

[28]  G. M. Greetham,et al.  Photophysical studies of CdTe quantum dots in the presence of a zinc cationic porphyrin. , 2012, Dalton transactions.

[29]  G. Wulff.  Fourty years of molecular imprinting in synthetic polymers: origin, features and perspectives , 2013, Microchimica Acta.

[30]  Sergey A Piletsky,et al.  Advances in the manufacture of MIP nanoparticles. , 2010, Trends in biotechnology.

[31]  Cuicui Liu,et al.  Molecularly imprinted polymer on ionic liquid-modified CdSe/ZnS quantum dots for the highly selective and sensitive optosensing of tocopherol , 2012 .

[32]  Maria Jose Ruedas-Rama,et al.  Azamacrocycle activated quantum dot for zinc ion detection. , 2008, Analytical chemistry.

[33]  Hydrophilic ionic liquid-passivated CdTe quantum dots for mercury ion detection. , 2013, Biosensors & bioelectronics.

[34]  Xiwen He,et al.  Molecularly imprinted polymer anchored on the surface of denatured bovine serum albumin modified CdTe quantum dots as fluorescent artificial receptor for recognition of target protein. , 2012, Biosensors & bioelectronics.

[35]  Jinghua Yu,et al.  Development of a novel deltamethrin sensor based on molecularly imprinted silica nanospheres embedded CdTe quantum dots. , 2011, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.