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hydroquinone-derivative
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Optical detection of phenolic compounds based on the surface plasmon resonance band of Au nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 71, Issue 1 , 2008 , Pages 199-203 ; 13861425 (ISSN) ; Alimohammadi, M ; Tashkhourian, J ; Razavian, S. M ; Sharif University of Technology
2008
Abstract
An indirect colorimetric method is presented for detection of trace amounts of hydroquinone (1), catechol (2) and pyrogallol (3). The reduction of AuCl4- to Gold nanoparticles (Au-NPs) by these phenolic compounds in the presence of cetyltrimethylammonium chloride (CTAC) produced very intense surface plasmon resonance peak of Au-NPs. The plasmon absorbance of Au-NPs allows the quantitative colorimetric detection of the phenolic compounds. The calibration curves derived from the changes in absorbance at λ = 568 nm were linear with concentration of hydroquinone, catechol and pyrogallol in the range of 7.0 × 10-7 to 1.0 × 10-4M, 6.0 × 10-6 to 2.0 × 10-4 M and 6.0 × 10-7 to 1.0 × 10-4 M,...
Simultaneous determination of epinephrine and acetaminophen concentrations using a novel carbon paste electrode prepared with 2,2′-[1,2 butanediylbis(nitriloethylidyne)]-bis-hydroquinone and TiO2 nanoparticles
, Article Colloids and Surfaces B: Biointerfaces ; Volume 76, Issue 1 , 2010 , Pages 82-87 ; 09277765 (ISSN) ; Beitollahi, H ; Sheikh Mohseni, M. A ; Benvidi, A ; Naeimi, H ; Nejati Barzoki, M ; Taghavinia, N ; Sharif University of Technology
2010
Abstract
A carbon paste electrode (CPE) modified with 2,2′-[1,2 butanediylbis(nitriloethylidyne)]-bis-hydroquinone (BBNBH) and TiO2 nanoparticles was used for the sensitive voltammetric determination of epinephrine (EP). The electrochemical response characteristics of the modified electrode toward EP and acetaminophen (AC) were investigated by cyclic and differential pulse voltammetry (CV and DPV). The results showed an efficient catalytic activity of the electrode for the electrooxidation of EP, which leads to a reduction in its overpotential by more than 270 mV. The effects of pH and potential sweep rate on the mechanism of the electrode process were investigated. The modified electrode exhibits an...
A mechanistic approach for toxicity and risk assessment of heavy metals, hydroquinone and microorganisms in cosmetic creams
, Article Journal of Hazardous Materials ; Volume 433 , 2022 ; 03043894 (ISSN) ; Shafeeq, A ; Siddiq, U ; Bashir, F ; Ahmad, T ; Athar, M ; Butt, M.T ; Ullah, S ; Mukhtar, A ; Hussien, M ; Lam, S. S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The demand and importance of fairness creams as a major cosmetic have increased significantly in recent years. However, some of these cosmetics contain heavy metals, hydroquinone and microorganism that can cause various health problems. Therefore, the aim of this study is to determine and examine the concentration of metals (i.e. Cd, Pb, Cr, Ni, Zn, Hg), hydroquinone and microorganisms in nine different fairness creams produced by local and international brands. The health risk assessment of the tested substances for consumers was accessed through systemic exposure dosage (SED), margin of safety (MoS), lifetime cancer risk (LCR), hazard quotient (HQ) and hazard index (HI). The concentration...