Automated microraft platform to identify and collect non-adherent cells successfully gene-edited with CRISPR-Cas9

Biosens Bioelectron. 2017 May 15;91:175-182. doi: 10.1016/j.bios.2016.12.019. Epub 2016 Dec 10.


Microraft arrays have been used to screen and then isolate adherent and non-adherent cells with very high efficiency and excellent viability; however, manual screening and isolation limits the throughput and utility of the technology. In this work, novel hardware and software were developed to automate the microraft array platform. The developed analysis software identified microrafts on the array with greater than 99% sensitivity and cells on the microrafts with 100% sensitivity. The software enabled time-lapse imaging and the use of temporally varying characteristics as sort criteria. The automated hardware released microrafts with 98% efficiency and collected released microrafts with 100% efficiency. The automated system was used to examine the temporal variation in EGFP expression in cells transfected with CRISPR-Cas9 components for gene editing. Of 11,499 microrafts possessing a single cell, 220 microrafts were identified as possessing temporally varying EGFP-expression. Candidate cells (n=172) were released and collected from the microraft array and screened for the targeted gene mutation. Two cell colonies were successfully gene edited demonstrating the desired mutation.

Keywords: CRISPR-Cas9; Cell array; Cell sorting; Cytometry; Microraft.

MeSH terms

  • Biosensing Techniques / instrumentation*
  • Biosensing Techniques / methods
  • CRISPR-Cas Systems*
  • Equipment Design
  • Genes, Reporter
  • Green Fluorescent Proteins / genetics
  • Humans
  • Image Processing, Computer-Assisted
  • K562 Cells
  • Leukemia / genetics
  • Mutation*
  • Splicing Factor U2AF / genetics*
  • Tissue Array Analysis / instrumentation*
  • Tissue Array Analysis / methods
  • Transfection


  • Splicing Factor U2AF
  • U2AF1 protein, human
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins