- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Free-label dual-signal responsive optical sensor by combining resonance Rayleigh scattering and colorimetry for sensitive detection of glutathione based on ultrathin MnO2 nanoflakes
摘要： Glutathione (GSH) plays a critical role in the living system and its abnormalities are closely associated with numerous clinical diseases. Thus, monitoring and detecting the content of GSH in the living system is still of great importance. Herein, a novel dual-signal responsive optical sensor is developed by using resonance Rayleigh scattering (RRS) and colorimetry for sensitive detection of GSH. In this sensor, MnO2 nanoflakes are used as both GSH recognizer and signal transducer of RRS and colorimetry. The solution of MnO2 nanoflakes shows strong RRS and absorption signals because MnO2 nanoflakes possess a large surface area and high molar extinction coefficient. However, MnO2 can be reduced to Mn2+ and MnO2 nanoflakes can be etched to small nanoparticles by GSH, causing both the RRS and absorption signals to decrease. Based on the change of RRS signal and absorbance of MnO2 nanoflakes, a novel dual-signal responsive optical sensor is successfully constructed to detect the content of GSH. The as-developed optical sensor toward GSH presents a favorable sensitivity with a detection limit of 0.033 and 0.67 μM for RRS and colorimetry, respectively. Furthermore, the as-developed approach is straightforward, quickly responsive, free-label, and cost-effective. More significantly, this method combines the advantages of RRS and colorimetry for the detection of GSH. Beyond this, the proposed RRS method has also been successfully utilized to detect the content of GSH in glutathione injection samples.
关键词： Glutathione,Resonance Rayleigh scattering,MnO2 nanoflakes,Colorimetry,Dual-signal
更新于2025-11-14 17:04:02
-
Surface functionalized quantum dots as biosensor for highly selective and sensitive detection of ppb level of propafenone
摘要： Monodispersed CdTe quantum dots (QDs) were prepared by using thioglycolic acid as surfactants in aqueous solution. The thioglycolic acid was chemically adsorbed on the surface of CdTe QDs that enables the QDs positively charged. In week acidic media, propafenone is positively charged, which can combine with the CdTe QDs to form larger ion-association complex via electrostatic attraction and hydrogen bond. Moreover, the formed ion-association complex could increase the intensity of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling-scattering (FDS) of CdTe QDs, and quench the CdTe QDs fluorescence. Importantly, under optimal experimental conditions, the increased RRS, SOS and FDS intensity, and quenched fluorescence intensity of CdTe QDs were in direct proportion to the propafenone concentration in a certain range, respectively. Among them, the RRS method exhibited the highest sensitivity. In a wide concentration range of propafenone from 0.003 to 7.0 mg mL?1, the detection limit could reach 0.96 ng mL?1, which was much lower than previously reported methods. To simulate practical applications, the possible foreign interfering substances were also investigated, such as common ions, amino acid, and glucide. The proposed method here is rapid, sensitive and shows promising application for detection of ppb level of propafenone in human serum.
关键词： Propafenone,CdTe quantum dots,Ion-association complex,Resonance Rayleigh scattering
更新于2025-09-16 10:30:52
-
Study on Resonance Rayleigh Scattering Spectra, Non-linear Scattering Spectra of Alizarin Red-Cetylpyridinium Bromide-Lead System and its Analytical Application
摘要： In pH 7.6 NH3·H2O medium, Alizarin red and cetylpyridinium bromide could react with lead to form ternary ion-association complex. As a result, the intensities of resonance Rayleigh scattering and the resonance non-linear scattering such as second-order scattering and frequency-doubling scattering were enhanced greatly. The maximum wavelength of resonance Rayleigh scattering, second-order scattering and frequency-doubling scattering was located at 288, 544 and 390 nm, respectively. The enhancement of the three scattering intensity (?I) was directly proportional to the concentration of lead in the range of 0.12-3.78 μg/mL for resonance Rayleigh scattering, 0.09-2.86 μg/mL for second-order scattering and 0.07-2.86 μg/mL for frequency-doubling scattering] and the detection limits (3σ) were 2.1ng/mL for resonance Rayleigh scattering method, 7.4 ng/mL for second-order scattering and 8.6 ng/mL for frequency-doubling scattering], respectively. Therefore, a new, high-sensitive method of resonance Rayleigh scattering and resonance non-linear scattering was developed to determine trace amount of lead. In this work, the characteristic of resonance Rayleigh scattering, second-order scattering and frequency-doubling scattering] spectra of the Alizarin red-cetylpyridinium bromide-Pb(II) system has been studied. Meanwhile, the influence of pH, resonance probe dosage, coexisting substances and other factors were investigated. The results show that the method exhibits a good selectivity, high sensitivity and easy operation. In addition, the mechanism of the enhancement of scattering spectra was discussed.
关键词： Resonance Rayleigh scattering,Lead,Cetylpyridinium bromide,Frequency doubling scattering,Alizarin red
更新于2025-09-04 15:30:14