Prior João A V, Santos João L M, Lima José L F C
CEQUP/Departamento de Química-Física, Faculdade de Farmácia da Universidade do Porto, Rua Aníbal Cunha 164, 4050, Porto, Portugal.
Anal Bioanal Chem. 2003 Apr;375(8):1234-9. doi: 10.1007/s00216-003-1813-5. Epub 2003 Mar 29.
In this work new strategies were exploited to implement multi-pumping flow systems relying on the utilisation of multiple devices that act simultaneously as sample-insertion, reagent-introduction, and solution-propelling units. The solenoid micro-pumps that were initially used as the only active elements of multi-pumping systems, and which were able to produce pulses of 3 to 25 microL, were replaced by syringe pumps with the aim of producing pulses between 1 and 4 microL. The performance of the developed flow system was assessed by using distinct sample-insertion strategies like single sample volume, merging zones, and binary sampling in the spectrophotometric determination of isoniazid in pharmaceutical formulations upon reaction with 1,2-naphthoquinone-4-sulfonate, in alkaline medium. The results obtained showed that enhanced sample/reagent mixing could be obtained with binary sampling and by using a 1 microL per step pump, even in limited dispersion conditions. Moreover, syringe pumps produce very reproducible flowing streams and are easily manipulated and controlled by a computer program, which is greatly simplified since they are the only active manifold component. Linear calibration plots up to 18.0 microg mL(-1), with a relative standard deviation of less than 1.48% (n=10) and a throughput of about 20 samples per hour, were obtained.
在这项工作中，开发了新策略来实现多泵流动系统，该系统依赖于多种装置的协同作用，这些装置同时充当样品注入、试剂引入和溶液推进单元。最初用作多泵系统唯一活性元件的电磁微型泵能够产生3至25微升的脉冲，为了产生1至4微升的脉冲，将其替换为注射泵。在碱性介质中，异烟肼与1,2-萘醌-4-磺酸盐反应后，采用不同的样品注入策略，如单一样品体积、合并区和二元采样，对所开发的流动系统在分光光度法测定药物制剂中异烟肼的性能进行了评估。所得结果表明，即使在有限的分散条件下，二元采样和使用每步1微升的泵也能实现样品/试剂的更好混合。此外，注射泵产生的流动流非常可重复，并且易于通过计算机程序进行操作和控制，由于它们是唯一的活性歧管组件，这大大简化了操作。获得了高达18.0微克/毫升的线性校准曲线，相对标准偏差小于1.48%（n = 10），每小时的通量约为20个样品。
