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![Research paper thumbnail of [The analysis of Gynostemma pentaphyllum (Thunb) Makino for Chinese crude drug by FTIR and FT-Raman]](https://a.academia-assets.com/images/blank-paper.jpg)
](Guang pu xue yu guang pu fen xi = Guang pu, 2004
The Gynostemma pentaphyllum is an important plant for Chinese crude drug. To qualitatively analys... more The Gynostemma pentaphyllum is an important plant for Chinese crude drug. To qualitatively analyse the Gynostemma pentaphyllum (Thunb) Makino, FTIR and FT-Raman were used to identify the contents of it. The results show, that the trough of each absorption in the picture of FTIR spectrum and the characteristic wave crest of each dispersion in the picture of FT-Raman spectrum had parallelism at their position, their relation pairs with each other. This is useful for the further on-line quantitative analysis and quality control of the Gynostemma pentaphyllum (Thunb) Makino. This approach provide a quickly and accurately determination method of crude drug without extraction and separation.
Biosensors and Bioelectronics, 2011
A simple electrochemical aptasensor for sensitive detection of thrombin was fabricated with Gquad... more A simple electrochemical aptasensor for sensitive detection of thrombin was fabricated with Gquadruplex horseradish peroxidase-mimicking DNAzyme (hemin/G-quadruplex system) and blocking reagent-horseradish peroxidase as dual signal-amplification scheme. Gold nanoparticles (nano-Au) were firstly electrodeposited onto single wall nanotube (SWNT)-graphene modified electrode surface for the immobilization of electrochemical probe of nickel hexacyanoferrates nanoparticles (NiHCFNPs). Subsequently, another nano-Au layer was electrodeposited for further immobilization of thrombin aptamer (TBA), which later formed hemin/G-quadruplex system with hemin. Horseradish peroxidases (HRP) then served as blocking reagent to block possible remaining active sites and avoided the non-specific adsorption. In the presence of thrombin, the TBA binded to thrombin and the hemin released from the hemin/G-quadruplex electrocatalytic structure, increasing steric hindrance of the aptasensor and decomposing hemin/G-quadruplex electrocatalytic structure, which finally decreased the electrocatalytic efficiency of aptasensor toward H 2 O 2 in the presence of NiHCFNPs with a decreased electrochemical signal. On the basis of the synergistic amplifying action, a detection limit as low as 2 pM for thrombin was obtained.
Analytica Chimica Acta, 2011
Vitamin C derivatives (VCDs) have been widely used as the alternative and stable sources of vitam... more Vitamin C derivatives (VCDs) have been widely used as the alternative and stable sources of vitamin C, and accordingly exhibit many new applications, such as anti-tumor and central nervous system drug delivery. In this study, their Ru(bpy) 3 2+ electrochemiluminescence (ECL) properties have been investigated for the first time using well-known ascorbyl phosphate and ascorbyl palmitate as representative VCDs. Ascorbyl phosphate and ascorbyl palmitate are VCDs with different substituted positions. Both of them increase Ru(bpy) 3 2+ ECL, indicating that other VCDs may also enhance Ru(bpy) 3 2+ ECL signal. The calibration plot for ascorbyl phosphate is linear from 3 × 10 −6 to 1.0 × 10 −3 M with a detection limit of 1.4 × 10 −6 M at a signal-to-noise ratio of 3. The relative standard deviation is 3.6% for six replicate measurements of 0.01 mM ascorbyl 2-phosphate solution. The proposed method is about one order of magnitude more sensitive than electrochemical and UV-vis methods for the determination of ascorbyl phosphate, and is used successfully for the determination of ascorbyl phosphate in whitening and moisturising body wash.
Guang pu xue yu guang pu fen xi = Guang pu, 2004
The Gynostemma pentaphyllum is an important plant for Chinese crude drug. To qualitatively analys... more The Gynostemma pentaphyllum is an important plant for Chinese crude drug. To qualitatively analyse the Gynostemma pentaphyllum (Thunb) Makino, FTIR and FT-Raman were used to identify the contents of it. The results show, that the trough of each absorption in the picture of FTIR spectrum and the characteristic wave crest of each dispersion in the picture of FT-Raman spectrum had parallelism at their position, their relation pairs with each other. This is useful for the further on-line quantitative analysis and quality control of the Gynostemma pentaphyllum (Thunb) Makino. This approach provide a quickly and accurately determination method of crude drug without extraction and separation.
Biosensors and Bioelectronics, 2011
A simple electrochemical aptasensor for sensitive detection of thrombin was fabricated with Gquad... more A simple electrochemical aptasensor for sensitive detection of thrombin was fabricated with Gquadruplex horseradish peroxidase-mimicking DNAzyme (hemin/G-quadruplex system) and blocking reagent-horseradish peroxidase as dual signal-amplification scheme. Gold nanoparticles (nano-Au) were firstly electrodeposited onto single wall nanotube (SWNT)-graphene modified electrode surface for the immobilization of electrochemical probe of nickel hexacyanoferrates nanoparticles (NiHCFNPs). Subsequently, another nano-Au layer was electrodeposited for further immobilization of thrombin aptamer (TBA), which later formed hemin/G-quadruplex system with hemin. Horseradish peroxidases (HRP) then served as blocking reagent to block possible remaining active sites and avoided the non-specific adsorption. In the presence of thrombin, the TBA binded to thrombin and the hemin released from the hemin/G-quadruplex electrocatalytic structure, increasing steric hindrance of the aptasensor and decomposing hemin/G-quadruplex electrocatalytic structure, which finally decreased the electrocatalytic efficiency of aptasensor toward H 2 O 2 in the presence of NiHCFNPs with a decreased electrochemical signal. On the basis of the synergistic amplifying action, a detection limit as low as 2 pM for thrombin was obtained.
Analytica Chimica Acta, 2011
Vitamin C derivatives (VCDs) have been widely used as the alternative and stable sources of vitam... more Vitamin C derivatives (VCDs) have been widely used as the alternative and stable sources of vitamin C, and accordingly exhibit many new applications, such as anti-tumor and central nervous system drug delivery. In this study, their Ru(bpy) 3 2+ electrochemiluminescence (ECL) properties have been investigated for the first time using well-known ascorbyl phosphate and ascorbyl palmitate as representative VCDs. Ascorbyl phosphate and ascorbyl palmitate are VCDs with different substituted positions. Both of them increase Ru(bpy) 3 2+ ECL, indicating that other VCDs may also enhance Ru(bpy) 3 2+ ECL signal. The calibration plot for ascorbyl phosphate is linear from 3 × 10 −6 to 1.0 × 10 −3 M with a detection limit of 1.4 × 10 −6 M at a signal-to-noise ratio of 3. The relative standard deviation is 3.6% for six replicate measurements of 0.01 mM ascorbyl 2-phosphate solution. The proposed method is about one order of magnitude more sensitive than electrochemical and UV-vis methods for the determination of ascorbyl phosphate, and is used successfully for the determination of ascorbyl phosphate in whitening and moisturising body wash.