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Papers by Ali Barati

Analytica Chimica Acta, 2021

Intrinsic dual-emissive carbon dots for efficient ratiometric detection of Cu 2+ and aspartic aci... more Intrinsic dual-emissive carbon dots for efficient ratiometric detection of Cu 2+ and aspartic acid, Analytica Chimica Acta,

Microchemical Journal, 2020

In this work, L-cysteine-capped CdTe quantum dots (L-Cys/CdTe QDs) were used as novel chiral prob... more In this work, L-cysteine-capped CdTe quantum dots (L-Cys/CdTe QDs) were used as novel chiral probes for in enantioselective recognition and quantitative determination of tyrosine (Tyr) enantiomers using both fluorescence and circular dichroism (CD) spectroscopies. Different quenching percentages in fluorescence of L-Cys/ CdTe QDs in the presence of similar concentrations of Tyr enantiomers were clearly observed. Quantum mechanical (QM) calculations were also used to confirm such different interactions of Land D-Tyr enantiomers with L-Cys/CdTe QDs. However, the CD spectroscopy exhibited higher capability and sensitivity, compared to fluorescence spectroscopy, to distinguish between these enantiomers. While, Tyr enantiomers provided no sensible CD signals at micromolar concentration levels, they exhibited remarkable and opposite CD spectra at these concentration levels in the presence of L-Cys/CdTe QDs. Under the optimized conditions, the CD signals of Land D-Tyr enantiomers showed good linear relationships with the concentrations of both enantiomers over the range of 10-80 µM with limit of detections (LODs) of 1.5 and 1.6 µM, respectively. This method was also successfully applied to enantiomeric excess determination of Tyr at the total concentration of 50 μM with a LOD of 1.2%.

Sensors and Actuators B: Chemical, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Cellular and Molecular Biology, 2018

Reviewing the mode of interaction between this kind of active pharmaceutical ingredients and DNA ... more Reviewing the mode of interaction between this kind of active pharmaceutical ingredients and DNA has received much more attention in current years. Anthracycline drugs such as Epirubicin are frequently used in cancer treatment for breast cancer treatment. In the present study, the Epirubicin -calf thymus DNA interaction was investigated by using spectroscopic, fluorimetric and molecular docking methods. Water-soluble quantum dots (QDs) with nanometric particle size fabricated and characterized by transmission electron microscope and photon correlation spectroscopy. The binding constant value and the free energy change for this interaction were obtained to be 3.00í—106 M-1 and -42.26 kJ mol-1, using the spectroscopic method and docking investigations, respectively. Additionally, fluorescent thioglycolic acid-capped CdTe QDs were used for investigation of EPI and DNA interaction. Epirubicin as a quencher quenched the fluorescence of CdTe QDs after electrostatic adsorption on the surfa...

Analytica chimica acta, Jan 8, 2017

In the present study, we developed a sensitive method based on fluorescence resonance energy tran... more In the present study, we developed a sensitive method based on fluorescence resonance energy transfer (FRET) for the determination of the BCR/ABL fusion gene, which is used as a biomarker to confirm the clinical diagnosis of both chronic myelogenous leukemia (CML) and acute lymphocytic leukemia (ALL). For this purpose, CdTe quantum dots (QDs) were conjugated to amino-modified 18-mer oligonucleotide ((N)DNA) to form the QDs-(N)DNA nanosensor. In the presence of methylene blue (MB) as an intercalator, the hybridization of QDs-(N)DNA with the target BCR/ABL fusion gene (complementary DNA), brings the MB (acceptor) at close proximity of the QDs (donor), leading to FRET upon photoexcitation of the QDs. The enhancement in the emission intensity of MB was used to follow up the hybridization, which was linearly proportional to concentration of the target complementary DNA in a range from 1.0 × 10(-9) to 1.25 × 10(-7) M. The detection limit of the proposed method was obtained to be 1.5 × 10(...

Journal of the Iranian Chemical Society, 2014

Anal. Methods, 2014

The overall fluorescence of a hybrid of two non-selective quantum dots (CQDs and CdTe QDs) has be... more The overall fluorescence of a hybrid of two non-selective quantum dots (CQDs and CdTe QDs) has been used for pattern-based discrimination of different analytes and simultaneous determination in a binary mixture of analytes.

Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 5, 2014

In this work, the kinetic fluorescence behavior of CdS quantum dots (QDs) in the presence of Cu(I... more In this work, the kinetic fluorescence behavior of CdS quantum dots (QDs) in the presence of Cu(II) was investigated. In contrast to some other transition metal ions such as Ag(I), Ni(II), and Hg(II), a gradual red-shift in the emission spectrum of CdS QDs was observed for Cu(II) during the reaction course. More investigations revealed the existence of two chemical components in the recorded kinetic data in the presence of Cu(II). Multivariate curve resolution-alternating least squares (MCR-ALS) method was applied in order to extract pure emission spectra and time-dependent profiles of these two components at different concentrations of Cu(II). The results obtained from resolving the data by MCR-ALS got some information about the mechanism of the interaction between CdS QDs and Cu(II) ions which were in good agreement with those reported in the literature. Moreover, the multivariate method of analysis, partial least-squares (PLS) method, was used to develop a multivariate calibratio...

Analytical Methods, 2014

ABSTRACT A simple, sensitive and efficient method known as manual shaking-enhanced, ultrasound-as... more ABSTRACT A simple, sensitive and efficient method known as manual shaking-enhanced, ultrasound-assisted dispersive liquid-liquid microextraction (MS-UADLLME) combined with high-performance liquid chromatography (HPLC) was developed for the extraction and determination of low concentrations of betamethasone (BM) and dexamethasone (DM) in serum and urine samples. A central composite chemometrics design was used for multivariate optimization of the effects of four different parameters influencing the extraction efficiency of the method. Response surface methodology (RSM) was applied to investigate the individual effects and possible interactions between the most effective variables, including volume of disperser and extraction solvent, ultrasound and manual shaking time on the chromatogram peak area of BM and DM. The respective linear range, detection limit (S/N = 3), and precision (n = 5) obtained were 0.4-550 ng mL−1, 0.18 ng mL−1 and 3.5-5.2% (for BM) and 0.2-430 ng mL−1, 0.09 ng mL−1 and 3.8-5.1% (for DM).