Abstract

The generation and manipulation of small aqueous droplets is an important issue for nano- and biotechnology, particularly, when using microfluidic devices. The production of very small droplets has been frequently carried out by applying intense local electric fields to the fluid, which requires power supplies and metallic electrodes. This procedure complicates the device and reduces its versatility. In this work, we present a novel and flexible, to the best of our knowledge, electrodeless optoelectronic method for the production of tiny droplets of biologically friendly aqueous fluids. Our method takes advantage of the photoinduced electric fields generated by the bulk photovoltaic effect in iron-doped lithium niobate crystals. Two substrate configurations, presenting the polar ferroelectric axis either parallel or perpendicular to the active surface, have been successfully tested. In both crystal geometries, small droplets on the femtoliter scale have been obtained, although with a different spatial distributions correlated with the symmetry of the photovoltaic fields. The overall results demonstrate the effectiveness of the optoelectronic method to produce femtoliter droplets, both with pure water and with aqueous solutions containing biological material.

© 2020 Optical Society of America

Optoelectronic manipulation of bio-droplets containing cells or macromolecules by active ferroelectric platforms

Andrés Puerto, José L. Bella, Carmen López-Fernández, Angel García-Cabañes, and Mercedes Carrascosa
Biomed. Opt. Express 12(10) 6601-6613 (2021)

Massive ordering and alignment of cylindrical micro-objects by photovoltaic optoelectronic tweezers

Iris Elvira, Juan F. Muñoz-Martínez, Álvaro Barroso, Cornelia Denz, José B. Ramiro, Angel García-Cabañes, Fernando Agulló-López, and Mercedes Carrascosa
Opt. Lett. 43(1) 30-33 (2018)

Photovoltaic splitting of water microdroplets on a y-cut LiNbO₃:Fe crystal coated with oil-infused hydrophobic insulating layers

Xiong Zhang, Kaifang Gao, Zuoxuan Gao, Zhitao Zan, Lihong Shi, Xiaohu Liu, Mengtong Wang, Hongjian Chen, and Wenbo Yan
Opt. Lett. 45(5) 1180-1183 (2020)

Generation and manipulation of oil-in-water micro-droplets by confined thermocapillary microvortices

Yilin Chen, Jianxin Yang, Jiayin Wu, Zongbao Li, Shaojing Liu, Huiqing Zhong, Ruixue Zhou, Aiping Luo, Ho-Pui Ho, Sailing He, Xiaobo Xing, and Lingling Shui
Opt. Lett. 45(7) 1998-2001 (2020)

Wavelength-scanning second-harmonic generation for determining absolute charge density at aqueous interfaces

Laetitia Dalstein, Jung-Ren Huang, and Yu-Chieh Wen
Opt. Lett. 45(13) 3733-3736 (2020)