Manipulating Femtoliter to Picoliter Droplets by Pins for Single Cell Analysis and Quantitative Biological Assay,Analytical Chemistry

当前位置： X-MOL 学术 › Anal. Chem. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Manipulating Femtoliter to Picoliter Droplets by Pins for Single Cell Analysis and Quantitative Biological Assay
Analytical Chemistry ( IF 6.7 ) Pub Date : 2018-04-12 00:00:00 , DOI: 10.1021/acs.analchem.8b00343
Xiao-Li Guo ₁ , Yan Wei ₁ , Qi Lou ₁ , Ying Zhu ₁ , Qun Fang ₁

Affiliation

Herein, we developed an automated and flexible system for performing miniaturized liquid–liquid reactions and assays in the femtoliter to picoliter range, by combining the contact printing and the droplet-based microfluidics techniques. The system mainly consisted of solid pins and an oil-covered hydrophilic micropillar array chip fixed on an automated x-y-z translation stage. A novel droplet manipulation mode called “dipping-depositing-moving” (DDM) was proposed, which was based on the programmable combination of three basic operations, dipping liquids and depositing liquids with the solid pins and moving the two-dimensional oil-covered hydrophilic pillar microchip. With the DDM mode, flexible generation and manipulation of small droplets with volumes down to 179 fL could be achieved. For overcoming the scale phenomenon specially appeared in picoliter-scale droplets, we used a design of water moat to protect the femtoliter to picoliter droplets from volume loss through the cover oil during the droplet generation, manipulation, reaction and assay processes. Moreover, we also developed a precise quantitative method, quantitative droplet dilution method, to accurately measure the volumes of femtoliter to picoliter droplets. To demonstrate its feasibility and adaptability, we applied the present system in the determination of kinetics parameter for matrix metalloproteinases (MMP-9) in 1.81 pL reactors and the measurement the activity of β-galactosidase in single cells (HepG2 cells) in picoliter droplet array. The ultrasmall volumes of the droplet reactors avoided the excessive dilution to the reaction solutions and enabled the highly sensitive measurement of enzyme activity in the single cell level.

中文翻译：

通过用于单细胞分析和定量生物学测定的针操作Femtoliter到Picoliter液滴

在这里，我们通过结合接触印刷和基于微滴的微流控技术，开发了一种自动化且灵活的系统，用于进行微升至皮升范围内的液-液反应和测定。该系统主要由实心销和固定在自动x - y - z上的覆盖油的亲水性微柱阵列芯片组成翻译阶段。提出了一种新颖的液滴操纵方式，称为“浸入-沉积-移动”（DDM），该模式基于三个基本操作的可编程组合，即使用固体销钉浸入液体和沉积液体，以及移动二维覆盖油的亲水性支柱微芯片。使用DDM模式，可以灵活地生成和处理体积低至179 fL的小液滴。为了克服特别是在皮升级液滴中出现的水垢现象，我们使用了一种水design设计，以保护飞升至皮升级液滴在液滴产生，操作，反应和测定过程中不因覆盖油而损失体积。此外，我们还开发了精确的定量方法，定量液滴稀释方法，准确测量飞升至皮升液滴的体积。为了证明其可行性和适应性，我们将本系统应用于确定1.81 pL反应器中基质金属蛋白酶（MMP-9）的动力学参数，以及测量微升液滴阵列中单细胞（HepG2细胞）中β-半乳糖苷酶的活性。液滴反应器的超小体积避免了对反应溶液的过度稀释，并使得能够在单细胞水平上对酶活性进行高度灵敏的测量。81 pL反应器并以微微升微滴阵列测量单细胞（HepG2细胞）中β-半乳糖苷酶的活性。液滴反应器的超小体积避免了对反应溶液的过度稀释，并使得能够在单细胞水平上对酶活性进行高度灵敏的测量。81 pL反应器并以微微升液滴阵列测量单细胞（HepG2细胞）中的β-半乳糖苷酶活性。液滴反应器的超小体积避免了对反应溶液的过度稀释，并使得能够在单细胞水平上对酶活性进行高度灵敏的测量。

更新日期：2018-04-12

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南