Evidence map›Paper›PMID 38716690›Full record

ArticleAnalytical chemistry2024

Reducing Cathodic Drift during Isoelectric Focusing Using Microscale Immobilized pH Gradient Gels.

Gabriela Lomeli, Amy E Herr

Abstract read
In one paragraph

Article in Analytical chemistry, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors.

Gabriela LomeliThe UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, California 94720, United States.ORCID 0000-0001-8603-1614
Amy E HerrThe UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, California 94720, United States.ORCID 0000-0002-6906-2985

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Microfluidic analytical tools play an important role in miniaturizing targeted proteomic assays for improved detection sensitivity, throughput, and automation. Microfluidic isoelectric focusing (IEF) can resolve proteoforms in lysate from low-to-single cell numbers. However, IEF assays often use carrier ampholytes (CAs) to establish a pH gradient for protein separation, presenting limitations like pH instability in the form of cathodic drift (migration of focused proteins toward the cathode). Immobilized pH gradient (IPG) gels reduce cathodic drift by covalently immobilizing the pH buffering components to a matrix. To our knowledge, efforts to implement IPG gels at the microscale have been limited to glass microdevices. To adapt IEF using IPGs to widely used microfluidic device materials, we introduce a polydimethylsiloxane (PDMS)-based microfluidic device and compare the microscale pH gradient stability of IEF established with IPGs, CAs, and a hybrid formulation of IPG gels and CAs (mixed-bed IEF). The PDMS-based IPG microfluidic device (μIPG) resolved analytes differing by 0.1 isoelectric point within a 3.5 mm separation lane over a 20 min focusing duration. During the 20 min duration, we observed markedly different cathodic drift velocities among the three formulations: 60.1 μm/min in CA-IEF, 2.5 μm/min in IPG-IEF (∼24-fold reduction versus CA-IEF), and 1.4 μm/min in mixed-bed IEF (∼43-fold reduction versus CA-IEF). Lastly, mixed-bed IEF in a PDMS device resolved green fluorescent protein (GFP) proteoforms from GFP-expressing human breast cancer cell lysate, thus establishing stability in lysate from complex biospecimens. μIPG is a promising and stable technique for studying proteoforms from small volumes.

Indexed as

DimethylpolysiloxanesIsoelectric FocusingElectrodesGelsHumansHydrogen-Ion ConcentrationLab-On-A-Chip DevicesMicrofluidic Analytical TechniquesProton-Motive ForcebaysilonDimethylpolysiloxanesGels

Identifiers

PMID38716690
PMCPMC11140684

What OpenQuestion holds

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LicenceCC BY
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.