Droplet-Based Analytical Chemistry Platforms Using Superhydrophobic and Superamphiphobic Surfaces

我们的实验室对开发用于化学分析的新型分离和检测方法感兴趣。化学分析构成了各种学科（例如环境，医学和“组学”相关研究领域）发现的基础。不断需要开发更快、需要更少样品且灵敏度增加的分析系统，这对于探测各种基质中的生物和化学系统至关重要。我们的实验室将开发基于液滴的（数字）微流体平台，将低摩擦表面（超疏水和超双疏）与基于磁性和重力的液滴驱动相结合，并将其应用于快速/灵敏的化学分析。我的计划将涉及新型无机和聚合物基材料的合成和表征，用于低摩擦表面涂层和探测新型微制造方法，以实现简易的设备制造（例如激光微加工）。超疏水/双疏表面的特征在于当液滴（例如水）置于其表面上时具有极高的接触角（150 °）。超疏水性/两亲性是通过表面化学和表面形貌的组合产生的。最小的表面粘附力使得能够通过在液滴上施加小的力（< 1 µN）来操纵液滴。可以通过将超顺磁性颗粒引入低摩擦表面上的水性液滴并施加磁场（速度超过50 cm/sec）来快速致动液滴。或者，我们已经表明，液滴可以使用溶解的顺磁性盐来操纵，即使它们的磁化率比超顺磁性颗粒的磁化率低约10，000倍。顺磁性颗粒可以用蛋白质、固定相或抗体功能化，以在单个液滴内进行化学反应。以这种方式，可以在化学分析之前进行多重样品制备（例如固相萃取、免疫捕获或衍生化）。我们将利用我的研究小组和我们的合作者在质谱法（MALDI和SDS-MS），荧光，电化学和吸光度检测方面的经验来分析各种分析物（例如生物标志物，生物合成酶，环境污染物等）。在样品制备后的液滴内。我们的实验室与许多学术和工业合作伙伴（例如NSERC Engage，Strategic和CREATE计划）合作，以进一步增强和国际化参与我的研究计划的研究人员的培训。在微加工，微流体，质谱和表面科学的经验相结合，将为学生提供相关的工业，政府和学术部门的技能。

Our laboratory is interested in the development of novel separation and detection methods for chemical analysis. Chemical analysis forms the basis for discovery in a wide variety of disciplines (e.g. environmental, medical and “omics” related research areas). The development of analysis systems that are faster, require less sample with increased sensitivity are in constant demand and become critical to probing e.g. biological and chemical systems in a variety of matrices. Our laboratory will develop droplet-based (digital) microfluidic platforms that combine low friction surfaces (superhydrophobic and super amphiphobic) with both magnetic and gravity-based droplet actuation and apply them to rapid/sensitive chemical analysis. My program will involve the synthesis and characterization of novel inorganic and polymer-based materials for low friction surface coatings and probe novel microfabrication methodologies to enable facile device fabrication (e.g. laser micromachining). Superhydrophobic/amphiphobic surfaces are characterized by extremely high contact angles (150 o) when droplets, of for example water, are placed upon their surface. The superhydrophobicity/amphiphobicity is generated through a combination of both surface chemistry and surface topography. The minimal surface adhesion enables the manipulation of droplets through the application of small forces (< 1 µN) on the droplet. A droplet can be rapidly actuated by introducing superparamagnetic particles to an aqueous droplet on a low friction surface, and applying a magnetic field (with speeds in excess of 50 cm/sec!). Alternatively we have shown that droplets can be manipulated using dissolved paramagnetic salts even though their magnetic susceptibility is approximately 10,000X less than that of the superparamagnetic particles. Paramagnetic particles can be functionalized with proteins, stationary phases, or with antibodies to conduct chemistry within the individual droplets. In this way multiplexed sample preparation prior to chemical analysis can be conducted (e.g. solid phase extraction, immuno-capture or derivatization). We will leverage my research group's and our collaborator's experience in mass spectrometry (MALDI and DESI-MS), fluorescence, electrochemical and absorbance detection to analyze of a variety of analytes (e.g. biomarkers, biosynthetic enzymes, environmental contaminants, etc.) within droplets following sample preparation. Our laboratory collaborates with a number of academic and industrial partners (e.g. NSERC Engage, Strategic and CREATE programs) to further augment and internationalize the training of researchers involved within my research program. The combination of experiences in microfabrication, microfluidics, mass spectrometry and surface science will provide students with a skill set relevant to the industrial, governmental and academic sectors.