Hsieh Kai-Ta, Liu Pei-Han, Urban Pawel L
Department of Applied Chemistry, National Chiao Tung University, 1001 University Rd, Hsinchu, 300, Taiwan.
Department of Applied Chemistry, National Chiao Tung University, 1001 University Rd, Hsinchu, 300, Taiwan; Institute of Molecular Science, National Chiao Tung University, 1001 University Rd, Hsinchu, 300, Taiwan.
Anal Chim Acta. 2015 Sep 24;894:35-43. doi: 10.1016/j.aca.2015.08.045. Epub 2015 Sep 1.
Most real samples cannot directly be infused to mass spectrometers because they could contaminate delicate parts of ion source and guides, or cause ion suppression. Conventional sample preparation procedures limit temporal resolution of analysis. We have developed an automated liquid-liquid extraction system that enables unsupervised repetitive treatment of dynamic samples and instantaneous analysis by mass spectrometry (MS). It incorporates inexpensive open-source microcontroller boards (Arduino and Netduino) to guide the extraction and analysis process. Duration of every extraction cycle is 17 min. The system enables monitoring of dynamic processes over many hours. The extracts are automatically transferred to the ion source incorporating a Venturi pump. Operation of the device has been characterized (repeatability, RSD = 15%, n = 20; concentration range for ibuprofen, 0.053-2.000 mM; LOD for ibuprofen, ∼0.005 mM; including extraction and detection). To exemplify its usefulness in real-world applications, we implemented this device in chemical profiling of pharmaceutical formulation dissolution process. Temporal dissolution profiles of commercial ibuprofen and acetaminophen tablets were recorded during 10 h. The extraction-MS datasets were fitted with exponential functions to characterize the rates of release of the main and auxiliary ingredients (e.g. ibuprofen, k = 0.43 ± 0.01 h(-1)). The electronic control unit of this system interacts with the operator via touch screen, internet, voice, and short text messages sent to the mobile phone, which is helpful when launching long-term (e.g. overnight) measurements. Due to these interactive features, the platform brings the concept of the Internet-of-Things (IoT) to the chemistry laboratory environment.
大多数实际样品不能直接注入质谱仪，因为它们可能会污染离子源和导向装置的精密部件，或导致离子抑制。传统的样品制备程序限制了分析的时间分辨率。我们开发了一种自动液液萃取系统，该系统能够对动态样品进行无监督的重复处理，并通过质谱（MS）进行即时分析。它采用了廉价的开源微控制器板（Arduino和Netduino）来指导萃取和分析过程。每个萃取周期的持续时间为17分钟。该系统能够对长达数小时的动态过程进行监测。萃取液通过文丘里泵自动转移到离子源中。该装置的操作已得到表征（重复性，相对标准偏差RSD = 15%，n = 20；布洛芬的浓度范围为0.053 - 2.000 mM；布洛芬的检测限约为0.005 mM；包括萃取和检测）。为了证明其在实际应用中的实用性，我们将该装置应用于药物制剂溶解过程的化学分析。在10小时内记录了市售布洛芬和对乙酰氨基酚片剂的时间溶解曲线。萃取 - MS数据集用指数函数拟合，以表征主要和辅助成分的释放速率（例如布洛芬，k = 0.43 ± 0.01 h⁻¹）。该系统的电子控制单元通过触摸屏、互联网、语音以及发送到手机的短文本消息与操作员进行交互，这在进行长期（例如过夜）测量时很有帮助。由于这些交互功能，该平台将物联网（IoT）的概念引入了化学实验室环境。
