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Wei Wang - One of the best experts on this subject based on the ideXlab platform.
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ultrasound assisted dispersive liquid liquid microextraction combined with high performance liquid chromatography fluorescence detection for sensitive determination of biogenic amines in rice wine samples
Journal of Chromatography A, 2009Co-Authors: Kejing Huang, Caiyun Wei, Weili Liu, Wanzhen Xie, Junfeng Zhang, Wei WangAbstract:Abstract Ultrasound-assisted dispersive liquid–liquid microextraction coupled with high-performance liquid chromatography-fluorescence detection was used for the extraction and determination of three biogenic amines including octopamine, tyramine and phenethylamine in rice wine samples. Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester was applied for derivatization of biogenic amines. Acetonitrile and 1-octanol were used as disperser solvent and extraction solvent, respectively. Extraction conditions including the type of extraction solvent, the volume of extraction solvent, ultrasonication time and Centrifuging time were optimized. After extraction and Centrifuging, analyte was injected rapidly into high-performance liquid chromatography and then detected with fluorescence. The calibration graph of the proposed method was linear in the range of 5–500 μg mL−1 (octopamine and tyramine) and 0.025–2.5 μg mL−1 (phenethylamine). The relative standard deviations were 2.4–3.2% (n = 6) and the limits of detection were in the range of 0.02–5 ng mL−1. The method was applied to analyze the rice wine samples and spiked recoveries in the range of 95.42–104.56% were obtained. The results showed that ultrasound-assisted dispersive liquid–liquid microextraction was a very simple, rapid, sensitive and efficient analytical method for the determination of trace amount of biogenic amines.
Atanasov Dmitro - One of the best experts on this subject based on the ideXlab platform.
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ORIGINAL EFFECTIVE, SAFE TECHNIQUE OF OBTAINING PLATELET RICH PLASMA BY CENTRIFUGATION OF THE BLOOD PLASMA IN MODIFIED SYRINGE CONTAINERS
Scientific Route OÜ, 2019Co-Authors: Chetverikov Sergiy, Atanasov DmitroAbstract:The aim: to develop, substantiate an effective and safe technology for producing PRP (platelet rich plasma). To quantify the substrate based on the recommended centrifugation protocols.Materials and methods: the effectiveness of the original harvesting protocol was evaluated by quantifying the number of platelets. The proposed technique is formed basing on the basic principles of double centrifugation of whole blood in test tubes with anticoagulant, separation with the release of a plasma layer with a high content of platelets.The Centrifuging mode for quantifying the effectiveness of the substrate was selected according to recommendations based on a study confirming maximum efficiency (160g×10min + 250g×15min).For quantitative evaluation, blood was collected from 10 healthy volunteers (7 men, 3 women) with an average age of 26.0±2.6, and centrifuged in standard mode. Quantitative evaluation of platelets of whole blood and the obtained PRP substrate was carried out with a semi-automatic analyzer.Results: the proposed technique is based on the use as a container for Centrifuging a syringe with a LuerLock design, which is hermetically sealed with a congruent plug, adapted by the external size of the centrifuge rotor bowl. Phase selection after centrifugation was performed by aspiration of the syringe contents after centrifugation is performed through a three-way valve. The substrate was obtained by repeated centrifugation of the contents, which allows obtaining a variable volume and platelet concentration in PRP. The amount of platelets (PLT) of whole blood is 227.0±57.0 thousand per ml. PLT PRP 945.0±279.0 thousand per ml.Conclusions: the proposed method of separation of whole blood with the release of the platelet rich plasma demonstrates high efficiency, which corresponds to the level of increasing the number of platelets in reducing the volume at the level of the best ready-made solutions.The equipment is economical and does not require highly specialized equipment and consumables. The proposed technique provides a wide choice to the performer in the received volume of the substrate
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EVALUATION OF Centrifuging REGIMES FOR THE PURPOSE OF OPTIMIZING THE PLATELET RICH PLASMA HARVESTING PROTOCOL
'OU Scientific Route', 2019Co-Authors: Chetverikov Sergiy, Atanasov DmitroAbstract:Aim: Based on the classical principles, to determine the optimal conditions for centrifugation, PRP harvesing (platelet-rich plasma). To conduct a quantitative assessment of the substrate obtained under different conditions of centrifugation. Materials and methods. Based on the basic principles of obtaining platelet-rich plasma (PRP) by Centrifuging in containers with an anticoagulant followed by phase separation to obtain the final substrate, the efficiency of the technique under the conditions of single and double centrifugation as well as under different conditions of acceleration and centrifugation was evaluated. Blood for follow-up was collected from 20 healthy volunteers (11 men, 9 women) average 25.3±4.1 in syringes of LuerLock design with ACD-A anticoagulant solution, and centrifuged. Centrifugation was carried out under controlled conditions using a centrifuge with rotating bowls of the rotor. Centrifugation was performed at an acceleration of 100-400g in time intervals up to 20 minutes. Activation of the substrate was performed with calcium chloride solution. Quantitative evaluation of platelets of whole blood and the final substrate of PRP was carried out with a semi-automatic analyzer. Results. The obtained results demonstrate the maximum level of harvesting efficiency when performing double centrifugation in the 150g×15 min+250g×10 min mode. Subject to this centrifugation protocol, it is possible to obtain a substrate that complies with the standardized requirements for PRP. The maximum level of an increase in the number of platelets in the substrate in comparison with whole blood is determined at the level of ×4.36 with concentration (volume reduction) x5 in comparison with the volume of whole blood. Conclusions. This study demonstrated the advantage of double Centrifuging modes over single modes. According to the results of the study, it was possible to determine the conditions for an optimal double-centrifugation mode (acceleration and duration), which allows us to achieve the most efficient concentration of the substrate
Chetverikov S. - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Centrifuging regimes for the purpose of optimizing the platelet rich plasma harvesting protocol
2019Co-Authors: Chetverikov S., Atanasov D.Abstract:Aim: Based on the classical principles, to determine the optimal conditions for centrifugation, PRP harvesing (platelet-rich plasma). To conduct a quantitative assessment of the substrate obtained under different conditions of centrifugation. Based on the basic principles of obtaining platelet-rich plasma (PRP) by Centrifuging in containers with an anticoagulant followed by phase separation to obtain the fnal substrate, the effciency of the technique under the conditions of single and double centrifugation as well as under different conditions of acceleration and centrifugation was evaluated. Blood for follow-up was collected from 20 healthy volunteers (11 men, 9 women) average 25.3±4.1 in syringes of LuerLock design with ACD-A anticoagulant solution, and centrifuged. Centrifugation was carried out under controlled conditions using a centrifuge with rotating bowls of the rotor. Centrifugation was performed at an acceleration of 100–400 g in time intervals up to 20 minutes. Activation of the substrate was performed with calcium chloride solution. Quantitative evaluation of platelets of whole blood and the fnal substrate of PRP was carried out with a semi-automatic analyzer. The obtained results demonstrate the maximum level of harvesting effciency when performing double centrifugation in the 150g × 15 min+250g × 10 min mode. Subject to this centrifugation protocol, it is possible to obtain a substrate that complies with the standardized requirements for PRP. The maximum level of an increase in the number of platelets in the substrate in comparison with whole blood is determined at the level of ×4.36 with concentration (volume reduction) ×5 in comparison with the volume of whole blood. This study demonstrated the advantage of double Centrifuging modes over single modes. According to the results of the study, it was possible to determine the conditions for an optimal double-centrifugation mode (acceleration and duration), which allows us to achieve the most effcient concentration of the substrate
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Original effective, safe technique of obtaining platelet rich plasma by centrifugation of the blood plasma in modified syringe containers
2019Co-Authors: Chetverikov S.Abstract:The aim: to develop, substantiate an effective and safe technology for producing PRP (platelet rich plasma). To quantify the substrate based on the recommended centrifugation protocols. The effectiveness of the original harvesting protocol was evaluated by quantifying the number of platelets. The proposed technique is formed basing on the basic principles of double centrifugation of whole blood in test tubes with anticoagulant, separation with the release of a plasma layer with a high content of platelets. The Centrifuging mode for quantifying the effectiveness of the substrate was selected according to recommendations based on a study confrming maximum effciency (160 g×10 min + 250 g×15 min). For quantitative evaluation, blood was collected from 10 healthy volunteers (7 men, 3 women) with an average age of 26.0±2.6, and centrifuged in standard mode. Quantitative evaluation of platelets of whole blood and the obtained PRP substrate was carried out with a semi-automatic analyzer. The proposed technique is based on the use as a container for Centrifuging a syringe with a LuerLock design, which is hermetically sealed with a congruent plug, adapted by the external size of the centrifuge rotor bowl. Phase selection after centrifugation was performed by aspiration of the syringe contents after centrifugation is performed through a three-way valve. The substrate was obtained by repeated centrifugation of the contents, which allows obtaining a variable volume and platelet concentration in PRP. The amount of platelets (PLT) of whole blood is 227.0±57.0 thousand per ml. PLT PRP 945.0±279.0 thousand per ml. The proposed method of separation of whole blood with the release of the platelet rich plasma demonstrates high effciency, which corresponds to the level of increasing the number of platelets in reducing the volume at the level of the best ready-made solutions. The equipment is economical and does not require highly specialized equipment and consumables. The proposed technique provides a wide choice to the performer in the received volume of the substrate
Kejing Huang - One of the best experts on this subject based on the ideXlab platform.
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ultrasound assisted dispersive liquid liquid microextraction combined with high performance liquid chromatography fluorescence detection for sensitive determination of biogenic amines in rice wine samples
Journal of Chromatography A, 2009Co-Authors: Kejing Huang, Caiyun Wei, Weili Liu, Wanzhen Xie, Junfeng Zhang, Wei WangAbstract:Abstract Ultrasound-assisted dispersive liquid–liquid microextraction coupled with high-performance liquid chromatography-fluorescence detection was used for the extraction and determination of three biogenic amines including octopamine, tyramine and phenethylamine in rice wine samples. Fluorescence probe 2,6-dimethyl-4-quinolinecarboxylic acid N-hydroxysuccinimide ester was applied for derivatization of biogenic amines. Acetonitrile and 1-octanol were used as disperser solvent and extraction solvent, respectively. Extraction conditions including the type of extraction solvent, the volume of extraction solvent, ultrasonication time and Centrifuging time were optimized. After extraction and Centrifuging, analyte was injected rapidly into high-performance liquid chromatography and then detected with fluorescence. The calibration graph of the proposed method was linear in the range of 5–500 μg mL−1 (octopamine and tyramine) and 0.025–2.5 μg mL−1 (phenethylamine). The relative standard deviations were 2.4–3.2% (n = 6) and the limits of detection were in the range of 0.02–5 ng mL−1. The method was applied to analyze the rice wine samples and spiked recoveries in the range of 95.42–104.56% were obtained. The results showed that ultrasound-assisted dispersive liquid–liquid microextraction was a very simple, rapid, sensitive and efficient analytical method for the determination of trace amount of biogenic amines.
Shouzhuo Yao - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous determination of melamine and related compounds by capillary zone electrophoresis
Food Control, 2010Co-Authors: Jingen Xia, Naiyuan Zhou, Yujun Liu, Bo Chen, Shouzhuo YaoAbstract:Abstract A simple, rapid and accurate method for the simultaneous determination of melamine and related compounds (ammeline, ammelide and cyanuric acid) by capillary zone electrophoresis with diode array detection (CZE–DAD) was developed and successfully applied in egg, dairy products and pet feed. Real samples were extracted with acetonitrile/water/diethylamine (80/18/2, v/v/v) and analyzed by CZE method directly after Centrifuging and filtering. Separation was performed by CZE using 40 mM disodium hydrogen phosphate buffer (pH 9.0) as running buffer, an applied voltage of +30 kV, and UV detection at 214 nm. Four targets were separated completely within 10 min. The optimized method demonstrated good performance concerning linearity ( r ⩾ 0.9964), precision (⩽4%), accuracy (82.2–101.6%), and enough sensitivity. And the proposed method was proved to have the merits of good separation, easy operation, short analysis time and low cost.