Electrokinetic stacking of particle zones in confined channels enabling their UV absorbance detection on microchips

Xia, Ling; Deb, Rajesh; Dutta, Debashis

doi:10.1016/j.aca.2020.08.019

Cited by 3 publications

(3 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Notice that such increase in bias ratio may also be observed upon increasing

Δ t_{I}

in our experiments which has a similar effect on sample transport as ramping up

φ_{i n j}

during stage I. To comprehend the results discussed above, we also performed gated injection [56–58] of the same dyes based on established procedures ensuring that the spatial standard deviation for the injected peaks was about 45 μm. These electrokinetic injections were performed after electrically floating reservoir 4 which rendered our microfluidic network identical to those employed for assessing electrokinetic injections in the literature at least from the point of view of the microchannel layout.…”

Section: Resultsmentioning

confidence: 61%

Reduction in sample injection bias using pressure gradients generated on chip

2021

Self Cite

View full text Add to dashboard Cite

Sample injection in microchip‐based capillary zone electrophoresis (CZE) frequently rely on the use of electric fields which can introduce differences in the injected volume for the various analytes depending on their electrophoretic mobilities and molecular diffusivities. While such injection biases may be minimized by employing hydrodynamic flows during the injection process, this approach typically requires excellent dynamic control over the pressure gradients applied within a microfluidic network. The current article describes a microchip device that offers this needed control by generating pressure gradients on‐chip via electrokinetic means to minimize the dead volume in the system. In order to realize the desired pressure‐generation capability, an electric field was applied across two channel segments of different depths to produce a mismatch in the electroosmotic flow rate at their junction. The resulting pressure‐driven flow was then utilized to introduce sample zones into a CZE channel with minimal injection bias. The reported injection strategy allowed the introduction of narrow sample plugs with spatial standard deviations down to about 45 μm. This injection technique was later integrated to a capillary zone electrophoresis process for analyzing amino acid samples yielding separation resolutions of about 4–6 for the analyte peaks in a 3 cm long analysis channel.

show abstract

“…Notice that such increase in bias ratio may also be observed upon increasing

Δ t_{I}

in our experiments which has a similar effect on sample transport as ramping up

φ_{i n j}

Section: Resultsmentioning

confidence: 61%

Reduction in sample injection bias using pressure gradients generated on chip

2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Likewise, a stir bar coated with AuNPs and combined with a microchip device has been shown to be effective in restoring DNA multi-arm link recovery for signal transduction and amplification purposes in the rapid detection of antibiotics [ 64 ]. In addition, some microfluidic pre-concentration/amplification techniques have been applied to biological samples such as isotachophoresis (ITP) [ 120 , 121 , 122 , 123 , 124 , 125 , 126 ], ion concentration polarization (ICP) [ 127 , 128 , 129 , 130 , 131 , 132 ], electrokinetic stacking (EKS) [ 133 , 134 , 135 , 136 , 137 ], field amplification stacking (FAS) [ 138 , 139 , 140 , 141 ], and multiplex electroanalytical techniques [ 142 , 143 ]. Although it has not been applied to milk analysis, it is also an important reference for future research.…”

Section: Discussionmentioning

confidence: 99%

Recent Advances in Microfluidic Devices for Contamination Detection and Quality Inspection of Milk

Lee

Kung

et al. 2021

Micromachines

View full text Add to dashboard Cite

Milk is a necessity for human life. However, it is susceptible to contamination and adulteration. Microfluidic analysis devices have attracted significant attention for the high-throughput quality inspection and contaminant analysis of milk samples in recent years. This review describes the major proposals presented in the literature for the pretreatment, contaminant detection, and quality inspection of milk samples using microfluidic lab-on-a-chip and lab-on-paper platforms in the past five years. The review focuses on the sample separation, sample extraction, and sample preconcentration/amplification steps of the pretreatment process and the determination of aflatoxins, antibiotics, drugs, melamine, and foodborne pathogens in the detection process. Recent proposals for the general quality inspection of milk samples, including the viscosity and presence of adulteration, are also discussed. The review concludes with a brief perspective on the challenges facing the future development of microfluidic devices for the analysis of milk samples in the coming years.

show abstract

“…To enhance the detection limit of paper-based platforms, it is frequently necessary to perform some form of sample preconcentration or amplification procedure prior to the analysis and detection process. Sample pre-concentration methods typically employ ion concentration polarization (ICP) [69,70], isotachophoresis (ITP) [71,72], electrokinetic stacking (EKS) [73,74], or multiplex electroanalytical techniques [75]. Meanwhile, sample amplification methods generally utilize loop-mediated isothermal amplification (LAMP) [76][77][78][79][80], catalytic hairpin assembly (CHA) amplification [81,82], or hybrid chain reaction (HCR) [82,83].…”

Section: Sample Concentration/amplificationmentioning

confidence: 99%

Lab-on-Paper Devices for Diagnosis of Human Diseases Using Urine Samples—A Review

et al. 2021

View full text Add to dashboard Cite

In recent years, microfluidic lab-on-paper devices have emerged as a rapid and low-cost alternative to traditional laboratory tests. Additionally, they were widely considered as a promising solution for point-of-care testing (POCT) at home or regions that lack medical infrastructure and resources. This review describes important advances in microfluidic lab-on-paper diagnostics for human health monitoring and disease diagnosis over the past five years. The review commenced by explaining the choice of paper, fabrication methods, and detection techniques to realize microfluidic lab-on-paper devices. Then, the sample pretreatment procedure used to improve the detection performance of lab-on-paper devices was introduced. Furthermore, an in-depth review of lab-on-paper devices for disease measurement based on an analysis of urine samples was presented. The review concludes with the potential challenges that the future development of commercial microfluidic lab-on-paper platforms for human disease detection would face.

show abstract

Electrokinetic stacking of particle zones in confined channels enabling their UV absorbance detection on microchips

Cited by 3 publications

References 33 publications

Reduction in sample injection bias using pressure gradients generated on chip

Reduction in sample injection bias using pressure gradients generated on chip

Recent Advances in Microfluidic Devices for Contamination Detection and Quality Inspection of Milk

Lab-on-Paper Devices for Diagnosis of Human Diseases Using Urine Samples—A Review

Contact Info

Product

Resources

About