Universidade Federal da Paraíba, Departamento de Química, João Pessoa, PB, Brazil.
Talanta. 2012 Aug 30;98:118-22. doi: 10.1016/j.talanta.2012.06.056. Epub 2012 Jun 29.
A method for the determination of phosphorus in mineralized biodiesel using a micro-flow-batch analyzer (μFBA) with solenoid micro-pumps was proposed. The samples were mineralized using an ashing procedure at 550 °C followed by dissolution of the residue. The determination of phosphorus was performed by employing the well-known molybdenum blue method. The measures of the absorbance were performed at 850 nm using an InfraRed LED integrated into the μFBA. Comparing with the reference method, no statistically significant differences were observed when applying the paired t-test at a 95% confidence level. Recovery study shows results between 97.9% and 105.8%. The proposed microsystem using solenoid micro-pumps presented satisfactory robustness and high sampling rate (190 h(-1)), with satisfactory reproducibility (relative standard deviation <4.5%, n=3), low reagents consumption (32 μL per analysis) and cost to build the device. Moreover, μFBA presents limit of detection (0.014 mg Kg(-1)), precision and accuracy compatible with the biodiesel regulations that establish a maximum concentration of 10 mg Kg(-1) (Brazil, USA, EU), suggesting that it is a good alternative for the determination of phosphorus in biodiesel.
提出了一种使用带有电磁微泵的微流动批处理分析仪 (μFBA) 测定矿化生物柴油中磷的方法。样品采用 550°C 的灰化程序进行矿化，然后溶解残渣。采用著名的钼蓝法测定磷。在 μFBA 中集成的红外 LED 测量吸光度，测量波长为 850nm。在 95%置信水平下应用配对 t 检验时，与参考方法相比，未观察到统计学上显著差异。回收研究表明结果在 97.9%至 105.8%之间。使用电磁微泵的提出的微系统具有令人满意的鲁棒性和高采样率（190 h(-1))，具有令人满意的重现性（相对标准偏差 <4.5%，n=3)），低试剂消耗（每次分析 32 μL) 和设备构建成本。此外，μFBA 具有与生物柴油法规兼容的检测限（0.014 mg Kg(-1))、精密度和准确度，该法规规定了 10 mg Kg(-1) 的最大浓度（巴西、美国、欧盟），表明它是生物柴油中磷测定的一种很好的替代方法。
