Microfluidic resonators with two parallel channels for independent sample loading and effective density tuning

Abstract

This paper reports doubly clamped microchannel embedded resonators with two independent and parallel channels integrated for effective sample density tuning for the first time. With the aid of such a unique design, each fluidic channel can be independently accessed thus different liquid samples can be loaded simultaneously. The proposed fluidic resonators are batch fabricated by depositing silicon nitride, polysilicon, and silicon nitride sequentially on top of a set of 4-inch silicon wafers and sacrificing the middle polysilicon layer with potassium hydroxide (KOH). The sacrificial process defines two parallel channels and releases doubly clamped beam resonators simultaneously. In addition, an off-chip vacuum clamp with optical and fluidic access is custom-made to operate each resonator with enhanced quality factor. The microfluidic resonators mounted on the custom vacuum clamp are thoroughly characterized with a laser Doppler vibrometer and used to measure the effective sample density ranging from 395 to 998 kg/m3.

Microarray detection method for pathogen genes by on-chip signal amplification using terminal deoxynucleotidyl transferase

“…In particular, because colorimetric sensor arrays do not require expensive analysis equipment for signal detection, they have the advantage of being simpler and more economical than fluorescent sensor arrays [7]. Small-sized portable microdevices based on various materials, such as glass [8], paper [9], silicon [10], polydimethylsiloxane [11,12], and cyclic olefin copolymers (COCs) [13,14], have been investigated for simplified onsite detection. COCs are suitable substrates for microarray chips because of their high chemical resistance, low water absorption, and high optical transparency [15][16][17][18].…”

Nanomechanical Molecular Mass Sensing Using Suspended Microchannel Resonators

“…In this regard, suspended microchannel resonators (SMR) have been demonstrated to be excellent tools for highly sensitive detection of both colloidal particles (measuring its buoyant mass) [ 14 , 15 , 16 , 17 ] and liquid properties (by measuring its mass density, viscosity, etc.) [ 18 , 19 , 20 , 21 , 22 ]. Among other nanomechanical techniques, SMR approach is characterized for placing a liquid inside the resonator while vibrating in vacuum or gaseous atmosphere.…”