Skip to main content
. Author manuscript; available in PMC: 2016 Nov 1.
Published in final edited form as: Eur Polym J. 2015 Feb 28;72:386–412. doi: 10.1016/j.eurpolymj.2015.02.022

Table 2.

Reported bioassays

Assay type Target Material Probe (captured
on gel particle)		 Detection Assay performance and
multiplexing		 Code Comments Ref.
nucleic acid detection hybridization assay 18nt oligonucleotide PEGDA oligonucleotide (covalent) direct detection (FITC-labeled targets)

  • specific detection of SNP (3-plex)

  • no LOD

 shape [33]
hybridization assay 18-2nt oligonucleotide PEGDA oligonucleotide (covalent) direct detection (FITC-labeled targets)

  • specific ( 3-plex)

  • LOD ~ single nM

 shape [37]
hybridization assay 21nt oligonucleotide PEGDA + polyacrylamide oligonucleotide (covalent) Complementary DNA

  • sensitivity: 0.66 pM

 structural color

  • comparison to glass beads and glass chip

 [107, 108, 111]
hybridization assay 20–200 nt oligonucleotides, microRNAs PEGDA oligonucleotide (covalent) direct detection (PicoGreen or Cy3-labeled targets) or labeling with SAPE (biotinylated targets)

  • 20–200nt targets: subattomole sensitivity

  • miRNA: 1 amol sensitivity

 graphical (extruded barcode)

  • mock complex environment using E.coli total RNA

 [35, 69]
hybridization assay 15nt oligonucleotide PEGDA oligonucleotide (covalent) direct detection (Cy3-labeled targets)

  • specific ( 2-plex)

  • no LOD

 color and graphical (bitcode)

  • particle mixing and immobilization using magnetic field

 [38]
miRNA microRNA PEGDA oligonucleotide (covalent) universal labeling scheme with T4 DNA ligase; rolling circle amplification; fluorescence readout

  • single amol sensitivity and high specific in a 12-plex assay

  • up to 300 aM sensitivity for 6 miRNA targets using amplification

 graphical (extruded barcode)

  • high-throughput scanner

  • detection from total RNA

  • 12-plex assay

 [70, 92]
mRNA in vitro transcribed mRNA PEGDA oligonucleotide (covalent) Scheme using capture extender, label extender, fluorescence readout

  • specific (3-plex)

  • 6 amol sensitivity

 graphical (extruded barcode)

  • gel porosity tuned to accommodate diffusion of large mRNA

 [45]
protein detection sandwich immunoassay 3 cytokines (IL-2, IL-4, TNFα) PEGDA monoclonal antibodies (covalent) biotinylated secondary antibody + SAPE

  • specific (3-plex)

  • LOD (3σ): 1 to 8 pg ml−1; dynamic range: 3 decades; CV: 8 to 11 %

 graphical (extruded barcode) [72]
direct immunoassay human IgG alginate anti-human IgG (non-covalent) direct detection FITC-labeled target

  • LOD (3σ): 2.2 μg ml−1; dynamic range: 5 – 40 μg ml−1

 spectral (QD)

  • Code partially interferes with readout

 [65]
direct immunoassay rabbit anti-mouse IgG; anti-mouse IgM PEGDA IgG and IgM (covalent) direct detection FITC-labeled target

  • quantitative up to 500 ng ml−1

  • specific (2-plex)

 shape [74]
aptamer-based sandwich assay α–thrombin; PEGDA aptamer sequence (covalent) biotinylated secondary aptamer or antibody + SAPE

  • LOD: 21.7pM (aptamer reporter); 4.09pM (antibody reporter); CV: <10%

 graphical (extruded barcode) [71]
aptamer-based displacement assay adenosine, thrombin, IgE PEGDA complementary oligonucleotide to aptamer sequence (covalent) target induces the release of the fluorescently labeled aptamer probe from particle

  • specific detection of 2mM targets (3-plex)

 structural color and shape [50]
small molecule detection enzymatic assay glucose PEGDA GOX/HRP (encapsulation) conversion of Amplex®Red into a fluorescent product

  • LOD: 0.2 mM

 shape [67]
enzymatic assay glucose alginate GOx (encapsulation) conversion of Amplex®Red into a fluorescent product

  • quantitative

 none (monoplex) [109]
enzymatic assay glucose PEGDA TRITC-ConA/FITC-Dextran (encapsulation) FRET assay

  • dynamic range: 1 – 10 mM

 none (monoplex) [39]

Abbreviations. CV: coefficient of variation; FITC: Fluorescein isothiocyanate; GOx: glucose oxidase; FRET: Förster resonance energy transfer; HRP: horseradish peroxidase; LOD: limit of detection; QD: quantum dot; SAPE: streptavidin phycoerythrin; SNP: single nucleotide polymorphism; TRITC-ConA: tetramethyl rhodamine isothiocyanate concanavalin A