{"id":6683,"date":"2026-06-27T23:25:28","date_gmt":"2026-06-27T21:25:28","guid":{"rendered":"https:\/\/zencellowl.com\/?p=6683"},"modified":"2026-06-27T23:37:38","modified_gmt":"2026-06-27T21:37:38","slug":"scratch-assay-protocol-imagej-guide","status":"publish","type":"post","link":"https:\/\/zencellowl.com\/zh\/scratch-assay-protocol-imagej-guide\/","title":{"rendered":"Scratch Assay Protocol &#038; ImageJ Analysis: Complete Guide"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"6683\" class=\"elementor elementor-6683\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-760ad34 e-flex e-con-boxed e-con e-parent\" data-id=\"760ad34\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-3b059ff elementor-widget elementor-widget-html\" data-id=\"3b059ff\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<!-- ============================================================\n     BLOG ARTICLE: Scratch Assay Protocol + ImageJ Guide\n     URL: zencellowl.com\/blog\/scratch-assay-protocol-imagej-guide\/\n     WordPress: Blog > New Post\n     Title: Scratch Assay Protocol & ImageJ Analysis: The Complete Guide (2025)\n     Category: Protocol Guides\n     Tags: scratch assay, wound healing assay, migration assay, ImageJ, cell migration\n     Featured Image: zerohour.png or L929 timelapse\n     Schema \u2192 Insert Headers & Footers \u2192 Footer Scripts\n     ============================================================ -->\n<style>\n  :root {\n    --teal:   #3aaea0;\n    --teal-d: #2d8f83;\n    --navy:   #1a2e3a;\n    --white:  #ffffff;\n    --off:    #f4f8f8;\n    --gray:   #6b7c85;\n    --border: #d8e6e4;\n    --font:   'Montserrat', sans-serif;\n  }\n  .bg * { box-sizing: border-box; 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border-collapse: collapse; margin: 20px 0; font-size: 13px; }\n  .bg-table th { background: var(--navy); color: var(--white); padding: 11px 14px; text-align: left; font-weight: 700; font-size: 12px; }\n  .bg-table th:first-child { border-radius: 6px 0 0 0; }\n  .bg-table th:last-child  { border-radius: 0 6px 0 0; }\n  .bg-table td { padding: 10px 14px; border-bottom: 1px solid var(--border); vertical-align: top; }\n  .bg-table tr:last-child td { border-bottom: none; }\n  .bg-table tr:nth-child(even) td { background: var(--off); }\n  .bg-ok   { color: var(--teal); font-weight: 700; }\n  .bg-no   { color: #c0392b; }\n  .bg-mid  { color: var(--gray); }\n\n  \/* HIGHLIGHT *\/\n  .bg-highlight { background: var(--navy); border-radius: 10px; padding: 24px 28px; margin: 28px 0; }\n  .bg-highlight p { color: rgba(255,255,255,.82); font-size: 15px; margin: 0; line-height: 1.7; }\n  .bg-highlight strong { color: var(--teal); }\n\n  \/* RELATED LINKS *\/\n  .bg-related { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; margin: 28px 0; }\n  .bg-rel { border: 1px solid var(--border); border-radius: 8px; padding: 16px 18px; text-decoration: none; display: block; transition: border-color .2s; }\n  .bg-rel:hover { border-color: var(--teal); }\n  .bg-rel-tag { font-size: 10px; font-weight: 700; letter-spacing: 1.5px; text-transform: uppercase; color: var(--teal); margin-bottom: 5px; }\n  .bg-rel h4 { font-size: 13px; font-weight: 700; color: var(--navy); line-height: 1.4; }\n\n  \/* CTA INLINE *\/\n  .bg-cta-inline { border: 1px solid var(--teal); border-radius: 10px; padding: 22px 26px; margin: 32px 0; display: flex; align-items: center; gap: 20px; flex-wrap: wrap; }\n  .bg-cta-inline p { font-size: 14px; color: var(--gray); flex: 1; min-width: 200px; margin: 0; }\n  .bg-cta-inline strong { color: var(--navy); }\n  .bg-btn { display: inline-block; background: var(--teal); color: var(--white); font-family: var(--font); font-size: 14px; font-weight: 700; padding: 11px 24px; border-radius: 6px; text-decoration: none; white-space: nowrap; }\n  .bg-btn:hover { background: var(--teal-d); color: var(--white); }\n\n  @media(max-width:640px) { .bg { padding: 0 18px 60px; } .bg-cta-inline { flex-direction: column; } }\n<\/style>\n\n<div class=\"bg\">\n\n<!-- META -->\n<div class=\"bg-meta\">\n  <span class=\"bg-tag\">Protocol Guide<\/span>\n  <span class=\"bg-tag\">Migration Assay<\/span>\n  <span class=\"bg-date\">June 2025 \u00b7 Updated<\/span>\n  <span class=\"bg-read\">\u23f1 12 min read<\/span>\n<\/div>\n\n<!-- TITLE -->\n<h1>Scratch Assay Protocol &amp; ImageJ Analysis: The Complete Guide (2025)<\/h1>\n\n<p class=\"bg-intro\">Everything you need to run a reproducible scratch assay \u2014 from cell seeding to publication-ready data. Includes a full step-by-step protocol, the complete ImageJ Wound Healing Size Tool guide, data interpretation, troubleshooting, and how to automate the entire workflow with zenCELL owl.<\/p>\n\n<!-- TOC -->\n<div class=\"bg-toc\">\n  <h3>Contents<\/h3>\n  <ol>\n    <li><a href=\"#what-is\">What is a scratch assay? Principle and terminology<\/a><\/li>\n    <li><a href=\"#vs\">Scratch assay vs. Transwell vs. Boyden chamber<\/a><\/li>\n    <li><a href=\"#protocol\">Complete scratch assay protocol \u2014 step by step<\/a><\/li>\n    <li><a href=\"#imagej\">ImageJ analysis \u2014 Wound Healing Size Tool guide<\/a><\/li>\n    <li><a href=\"#results\">Calculating % wound closure and migration rate<\/a><\/li>\n    <li><a href=\"#proliferation\">Migration vs. proliferation \u2014 Mitomycin C<\/a><\/li>\n    <li><a href=\"#troubleshooting\">Troubleshooting common problems<\/a><\/li>\n    <li><a href=\"#automated\">Automated alternative: zenCELL owl<\/a><\/li>\n  <\/ol>\n<\/div>\n\n<!-- SECTION 1: WHAT IS -->\n<h2 id=\"what-is\">1. What is a scratch assay? Principle and terminology<\/h2>\n\n<p>The <strong>scratch assay<\/strong> \u2014 also called the <strong>wound healing assay<\/strong> or <strong>cell migration assay<\/strong> \u2014 is one of the most widely used in vitro techniques in cell biology. It is simple, inexpensive and provides quantitative data on collective cell migration.<\/p>\n\n<h3>The principle in brief<\/h3>\n<p>A confluent monolayer of adherent cells is physically scratched to create a cell-free gap. Cells at the wound edge lose contact inhibition and begin migrating collectively to close the gap. The rate and extent of closure is monitored over time by microscopy and quantified as <strong>% wound closure<\/strong> or <strong>migration rate (\u00b5m\/h)<\/strong>.<\/p>\n\n<div class=\"bg-tip\">\n  <strong>Why \"wound healing assay\"?<\/strong>\n  <p>The scratch assay mimics the in vivo wound healing process \u2014 where epithelial or endothelial cells migrate collectively to repair a tissue defect. This makes it a relevant model for studying cancer invasion, angiogenesis, tissue regeneration and drug effects on cell motility.<\/p>\n<\/div>\n\n<h3>Scratch assay vs. wound healing assay vs. migration assay \u2014 what is the difference?<\/h3>\n<table class=\"bg-table\">\n  <tr><th>Term<\/th><th>What it specifically means<\/th><th>When to use<\/th><\/tr>\n  <tr><td><strong>Scratch assay<\/strong><\/td><td>The method: a gap physically created by a pipette tip, stencil or device in a monolayer<\/td><td>Describing experimental setup in lab context<\/td><\/tr>\n  <tr><td><strong>Wound healing assay<\/strong><\/td><td>The biological model: cells migrating to close a wound, mimicking in vivo tissue repair<\/td><td>Regenerative medicine, dermatology, wound biology<\/td><\/tr>\n  <tr><td><strong>Cell migration assay<\/strong><\/td><td>Umbrella term covering scratch, Transwell, Boyden chamber and other methods<\/td><td>Publications, grants, method sections<\/td><\/tr>\n  <tr><td><strong>2D migration assay<\/strong><\/td><td>Specifically the scratch assay, distinguishing from 3D invasion or Transwell methods<\/td><td>When explicitly contrasting with 3D models<\/td><\/tr>\n<\/table>\n\n<p>All three terms are used interchangeably in the literature. In publications, \"wound healing assay\" and \"scratch assay\" are equally accepted \u2014 both are correct for the same experimental approach.<\/p>\n\n<!-- SECTION 2: VS -->\n<h2 id=\"vs\">2. Scratch assay vs. Transwell vs. Boyden chamber \u2014 which migration assay to use?<\/h2>\n\n<p>The scratch assay is the right choice for most migration studies \u2014 but understanding when other methods are more appropriate will help you make the right decision for your experimental question.<\/p>\n\n<table class=\"bg-table\">\n  <tr><th>Method<\/th><th>Measures<\/th><th>Kinetic data?<\/th><th>Complexity<\/th><th>Best for<\/th><\/tr>\n  <tr><td><strong>Scratch \/ Wound Healing Assay<\/strong><\/td><td>Collective 2D migration<\/td><td class=\"bg-ok\">\u2713 Full timelapse<\/td><td class=\"bg-ok\">Low<\/td><td>Drug screening, wound healing models, HTS, first migration experiments<\/td><\/tr>\n  <tr><td><strong>Transwell Migration<\/strong><\/td><td>Individual cell chemotaxis<\/td><td class=\"bg-no\">Endpoint only<\/td><td class=\"bg-mid\">Medium<\/td><td>Directional migration toward a gradient, serum chemotaxis<\/td><\/tr>\n  <tr><td><strong>Boyden Chamber (Invasion)<\/strong><\/td><td>Invasion through Matrigel<\/td><td class=\"bg-no\">Endpoint only<\/td><td class=\"bg-no\">Higher<\/td><td>Invasive potential of cancer cells through ECM<\/td><\/tr>\n  <tr><td><strong>\u00b5-Slide Insert (ibidi)<\/strong><\/td><td>Collective 2D migration, defined gap<\/td><td class=\"bg-ok\">\u2713 If live imaged<\/td><td class=\"bg-mid\">Medium<\/td><td>When ECM damage from pipette scratching must be avoided<\/td><\/tr>\n<\/table>\n\n<div class=\"bg-tip\">\n  <strong>When to choose the scratch assay<\/strong>\n  <p>Choose the scratch assay when you need: kinetic data on collective migration, an inexpensive setup, compatibility with drug screening across many conditions, or a model for wound healing in vitro. It is the default first choice for most cell migration studies in cancer biology, regenerative medicine and pharmacology.<\/p>\n<\/div>\n\n<!-- SECTION 3: PROTOCOL -->\n<h2 id=\"protocol\">3. Complete scratch assay protocol \u2014 step by step<\/h2>\n\n<p>This protocol covers the standard 24-well plate format with manual pipette tip scratch creation. For a standardised, reproducible alternative, see the <a href=\"https:\/\/zencellowl.com\/scratchmaker\/\" style=\"color:var(--teal);text-decoration:none;font-weight:700;\">ScratchMaker system<\/a>.<\/p>\n\n<h3>Materials needed<\/h3>\n<ul>\n  <li>Adherent cell line of choice (fibroblasts, epithelial, endothelial, cancer cells)<\/li>\n  <li>24-well tissue culture plates (standard or fibronectin\/collagen-coated)<\/li>\n  <li>P200 pipette with tips<\/li>\n  <li>Complete growth medium + serum-reduced medium (0.5\u20132% FBS)<\/li>\n  <li>PBS (for washing)<\/li>\n  <li>Mitomycin C (optional \u2014 10 \u00b5g\/mL stock solution)<\/li>\n  <li>Brightfield microscope or zenCELL owl in-incubator imager<\/li>\n  <li>Marker pen (for labelling the plate bottom)<\/li>\n<\/ul>\n\n<!-- PART 1 -->\n<div class=\"bg-proto\">\n  <div class=\"bg-proto-head\">\n    <h4>Part 1 \u2014 Cell preparation and seeding (Day before)<\/h4>\n    <p>Goal: achieve a dense, healthy monolayer of >95% confluence at the time of scratching<\/p>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">1<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Prepare cells for seeding<\/h5>\n      <p>Passage cells 1\u20132 days before seeding to ensure cells are in exponential growth phase. Check viability before seeding \u2014 target \u226590% viable cells.<\/p>\n      <span class=\"bg-badge bg-gray\">\u23f1 Day before experiment<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">2<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Seed cells in 24-well plate<\/h5>\n      <p>Seed at a density that reaches >95% confluence within 16\u201324 hours of incubation.<\/p>\n      <ul>\n        <li><strong>Typical density:<\/strong> 100,000\u2013200,000 cells\/well (adjust per cell line \u2014 fast-dividing lines need lower density)<\/li>\n        <li><strong>Volume:<\/strong> 500 \u00b5L\u20131 mL complete medium per well<\/li>\n        <li><strong>Incubate:<\/strong> 37\u00b0C, 5% CO\u2082, overnight (16\u201324h)<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-gray\">\u23f1 Overnight incubation<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">3<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Verify confluence before proceeding<\/h5>\n      <p>Confirm >95% confluence under the microscope. Subconfluent monolayers produce uneven gap edges and unreliable migration data. If not yet confluent, incubate for additional 2\u20134h.<\/p>\n      <span class=\"bg-badge bg-warn\">\u26a0\ufe0f Do not proceed if confluence &lt;90%<\/span>\n    <\/div>\n  <\/div>\n<\/div>\n\n<!-- PART 2 -->\n<div class=\"bg-proto\">\n  <div class=\"bg-proto-head\">\n    <h4>Part 2 \u2014 Scratch creation (Day of experiment, T=0)<\/h4>\n    <p>Goal: create a reproducible, straight gap of consistent width across all wells<\/p>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">4<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Optional: Mitomycin C pre-treatment<\/h5>\n      <p>If you need to separate migration from proliferation, add Mitomycin C (10 \u00b5g\/mL) to all wells 2 hours before scratching. Aspirate before scratch creation.<\/p>\n      <ul>\n        <li><strong>Required:<\/strong> assays >12h, fast-cycling cell lines (HeLa, A549), studies on drugs affecting proliferation<\/li>\n        <li><strong>Optional:<\/strong> slow cells, short assays (&lt;12h), when combined effects are acceptable<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-gray\">\u23f1 2h pre-treatment<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">5<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Create the scratch with a pipette tip<\/h5>\n      <p>Using a P200 pipette tip, draw a single straight line across the well in one continuous motion.<\/p>\n      <ul>\n        <li><strong>Angle:<\/strong> hold the tip perpendicular (90\u00b0) to the plate bottom \u2014 angled tips produce wider, irregular scratches<\/li>\n        <li><strong>Pressure:<\/strong> moderate and consistent \u2014 pressing too hard causes the tip to skip; too light produces curved lines<\/li>\n        <li><strong>Direction:<\/strong> one direction only \u2014 no back-and-forth movement<\/li>\n        <li><strong>Tip size:<\/strong> P200 is standard (~400\u2013600 \u00b5m width); P20 for narrower gaps<\/li>\n        <li><strong>Reference mark:<\/strong> draw a line on the plate bottom with a marker to ensure the same imaging position at every timepoint<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-warn\">\u26a0\ufe0f Manual scratch: \u00b130\u201360% width variability between wells and operators<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">6<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Wash and replace medium \u2014 T=0 starts now<\/h5>\n      <p>Immediately after scratching, gently aspirate medium and wash once with pre-warmed PBS. Replace with fresh medium \u00b1 compound.<\/p>\n      <ul>\n        <li><strong>Serum concentration:<\/strong> 0.5\u20132% FBS reduces proliferation contribution; serum-free for migration-only readout<\/li>\n        <li><strong>Add compound:<\/strong> treatments are added at this point at 1\u00d7 final concentration<\/li>\n        <li><strong>Volume:<\/strong> 500 \u00b5L\/well \u2014 fills evenly without creating turbulence at the wound edge<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-teal\">T = 0 \u2014 reference wound area defined<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">7<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Capture T=0 image within 15 minutes<\/h5>\n      <p>Image all wells within 15 minutes of scratching. This is your baseline wound area for all % closure calculations. Position the microscope at the same reference mark for each well.<\/p>\n      <p style=\"margin-top:6px;\"><strong>With zenCELL owl:<\/strong> place the plate on the device, set imaging interval (5\u201330 min), press Start. T=0 is captured automatically and all subsequent timepoints run unattended.<\/p>\n      <span class=\"bg-badge bg-teal\">zenCELL owl: fully automated from this point<\/span>\n    <\/div>\n  <\/div>\n<\/div>\n\n<!-- PART 3 -->\n<div class=\"bg-proto\">\n  <div class=\"bg-proto-head\">\n    <h4>Part 3 \u2014 Imaging and monitoring<\/h4>\n    <p>Goal: capture complete kinetics of gap closure with sufficient temporal resolution<\/p>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">8<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Manual imaging (conventional approach)<\/h5>\n      <p>Remove plate from incubator, image under inverted brightfield microscope at the reference mark, return plate to incubator.<\/p>\n      <ul>\n        <li><strong>Typical intervals:<\/strong> 0h, 4h, 8h, 12h, 24h \u2014 or 0h, 8h, 24h for faster assays<\/li>\n        <li><strong>Consistent position:<\/strong> use the reference mark on the plate bottom at every timepoint<\/li>\n        <li><strong>Limitation:<\/strong> temperature shock, CO\u2082 loss, contamination risk at every removal; kinetics between timepoints are missing<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-warn\">\u26a0\ufe0f Incomplete kinetics \u2014 intervention disrupts culture at every timepoint<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">9<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Automated imaging with zenCELL owl (recommended)<\/h5>\n      <p>zenCELL owl sits inside the incubator and images all 24 wells every 5\u201330 minutes, continuously, without any plate removal.<\/p>\n      <ul>\n        <li><strong>Interval for scratch assay:<\/strong> every 5\u201330 minutes (captures full kinetic curve)<\/li>\n        <li><strong>All 24 wells:<\/strong> imaged simultaneously under identical conditions<\/li>\n        <li><strong>Software:<\/strong> automatically calculates confluence per well at every timepoint \u2192 gap area \u2192 % closure \u2192 t\u00bd<\/li>\n        <li><strong>No intervention:<\/strong> zero temperature loss, zero CO\u2082 disruption, zero contamination risk<\/li>\n        <li><strong>Retrospective access:<\/strong> every timepoint retained \u2014 analyse any moment post-experiment<\/li>\n      <\/ul>\n      <span class=\"bg-badge bg-teal\">\u2713 24 conditions \u00b7 \u2713 Complete kinetics \u00b7 \u2713 Zero intervention<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">10<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Assay duration and stopping point<\/h5>\n      <p>Run until control wells reach 80\u2013100% closure. Do not over-run \u2014 fully closed wounds cannot be quantified.<\/p>\n      <ul>\n        <li><strong>Fast migrating cells<\/strong> (HeLa, MDA-MB-231, A549): 12\u201318h to full closure<\/li>\n        <li><strong>Moderate migrating cells<\/strong> (MCF-7, Caco-2, HUVEC): 20\u201336h<\/li>\n        <li><strong>Slow migrating cells<\/strong> (primary fibroblasts, hMSC): 36\u201372h<\/li>\n      <\/ul>\n    <\/div>\n  <\/div>\n<\/div>\n\n<div class=\"bg-cta-inline\">\n  <p><strong>Running scratch assays regularly?<\/strong> The ScratchMaker creates physiologically clean gaps with &lt;5% width variability \u2014 no pipette tip, no mechanical damage to cells or ECM. Combined with zenCELL owl, the complete workflow is automated and reproducible.<\/p>\n  <a href=\"https:\/\/zencellowl.com\/wound-healing-assay\/\" class=\"bg-btn\">See the complete system \u2192<\/a>\n<\/div>\n\n<!-- SECTION 4: IMAGEJ -->\n<h2 id=\"imagej\">4. ImageJ scratch assay analysis \u2014 Wound Healing Size Tool guide<\/h2>\n\n<p>The most widely used free tool for scratch assay image analysis is the <strong>Wound Healing Size Tool<\/strong> plugin for ImageJ\/Fiji, developed by Suarez-Arnedo et al. and published in <em>PLoS ONE<\/em> in 2020 \u2014 cited 979 times as of 2025. It automatically detects wound boundaries and calculates wound area, width and coverage without manual tracing.<\/p>\n\n<div class=\"bg-tip\">\n  <strong>Which ImageJ plugin for scratch assay analysis?<\/strong>\n  <p><strong>Wound Healing Size Tool<\/strong> (Suarez-Arnedo et al., PLoS ONE 2020) \u2014 most cited, simple to use, batch mode available. Best starting point. &nbsp;|&nbsp; <strong>MRI Wound Healing Tool<\/strong> (Montpellier Resources Imagerie) \u2014 adds cell orientation\/coherency analysis within the migrating front. &nbsp;|&nbsp; <strong>CSMA<\/strong> (IEEE Access 2025) \u2014 improved detection of cells migrating into the wound centre. &nbsp;|&nbsp; <strong>TScratch<\/strong> \u2014 MATLAB-based, good for large batch processing.<\/p>\n<\/div>\n\n<h3>Step-by-step: Wound Healing Size Tool in ImageJ\/Fiji<\/h3>\n\n<div class=\"bg-proto\">\n  <div class=\"bg-proto-head\">\n    <h4>ImageJ Wound Healing Analysis Protocol<\/h4>\n    <p>Wound Healing Size Tool (Suarez-Arnedo et al., PLoS ONE 2020)<\/p>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">1<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Install Fiji (ImageJ with plugins)<\/h5>\n      <p>Download Fiji from <strong>fiji.sc<\/strong> \u2014 free, open-source, works on Windows, Mac and Linux. Fiji includes most analysis plugins pre-installed.<\/p>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">2<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Download and install the Wound Healing Size Tool<\/h5>\n      <p>Search \"Wound_healing_size_tool_updated\" on the ImageJ plugin repository or the original PLoS ONE publication. Download the <code>.zip<\/code> file, unzip, and place the <code>.ijm<\/code> file into the <code>Fiji.app\/plugins\/<\/code> folder. Restart Fiji.<\/p>\n      <span class=\"bg-badge bg-teal\">Plugins menu \u2192 Wound_healing_size_tool<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">3<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Open your scratch assay image in 8-bit greyscale<\/h5>\n      <p>File \u2192 Open to load a single image. For a timelapse series: File \u2192 Import \u2192 Image Sequence \u2192 select the folder. Then convert to 8-bit: <strong>Image \u2192 Type \u2192 8-bit<\/strong>. This is required for the plugin's intensity-based wound detection algorithm.<\/p>\n      <span class=\"bg-badge bg-teal\">Image \u2192 Type \u2192 8-bit<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">4<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Set the scale (pixels \u2192 \u00b5m)<\/h5>\n      <p>Go to <strong>Analyze \u2192 Set Scale<\/strong>. Enter the pixel\/\u00b5m calibration from your microscope. This converts wound width from pixels to \u00b5m and enables migration rate calculation in \u00b5m\/h. Check \"Global\" to apply to all subsequent images in the session.<\/p>\n      <span class=\"bg-badge bg-teal\">Analyze \u2192 Set Scale \u2192 known distance in \u00b5m<\/span>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">5<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Run the Wound Healing Size Tool<\/h5>\n      <p>Plugins \u2192 Wound_healing_size_tool. The plugin opens a dialogue with configurable parameters:<\/p>\n      <ul>\n        <li><strong>Threshold:<\/strong> adjust if cell\/background contrast is low (start with default, increase if edges are missed)<\/li>\n        <li><strong>Save results:<\/strong> \u2713 check \u2014 auto-exports CSV to your chosen folder<\/li>\n        <li><strong>Show binary image:<\/strong> \u2713 check for first run \u2014 lets you validate wound detection visually<\/li>\n        <li><strong>Add to ROI Manager:<\/strong> optional \u2014 shows detected wound outline<\/li>\n      <\/ul>\n      <p>Click OK. The plugin detects wound boundaries using pixel intensity variance \u2014 wound pixels have similar intensity values, cell pixels have high variance.<\/p>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">6<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Read results from the Results window<\/h5>\n      <p>The Results window displays per image:<\/p>\n      <ul>\n        <li><strong>Wound area (\u00b5m\u00b2):<\/strong> total cell-free area<\/li>\n        <li><strong>Wound width average (\u00b5m):<\/strong> mean distance between wound edges<\/li>\n        <li><strong>Wound coverage (%):<\/strong> wound area as % of total image area<\/li>\n        <li><strong>Width standard deviation:<\/strong> indicates scratch straightness \u2014 use this to identify irregular scratches<\/li>\n      <\/ul>\n    <\/div>\n  <\/div>\n  <div class=\"bg-step\">\n    <div class=\"bg-step-n\">7<\/div>\n    <div class=\"bg-step-b\">\n      <h5>Export CSV and calculate % wound closure in Excel or GraphPad<\/h5>\n      <p>File \u2192 Save As \u2192 Results (CSV). Import into GraphPad Prism or Excel. Calculate % wound closure using the T=0 wound area as reference (see formulas below).<\/p>\n      <span class=\"bg-badge bg-teal\">Export: CSV \u00b7 GraphPad Prism \u00b7 Excel<\/span>\n    <\/div>\n  <\/div>\n<\/div>\n\n<div class=\"bg-tip\">\n  <strong>Tip: if the plugin misses wound edges<\/strong>\n  <p>Convert to 8-bit, then increase image contrast before running: <strong>Image \u2192 Adjust \u2192 Brightness\/Contrast \u2192 Auto<\/strong>. The plugin relies on intensity difference between the wound (uniform background) and cell monolayer (high variance). Low contrast images produce poor detection. Phase contrast images typically work better than standard brightfield for this reason.<\/p>\n<\/div>\n\n<!-- SECTION 5: RESULTS -->\n<h2 id=\"results\">5. Calculating % wound closure and migration rate<\/h2>\n\n<p>Once you have wound area measurements at each timepoint, calculate the standard readouts:<\/p>\n\n<h3>% Wound closure<\/h3>\n<p>The most common and comparable metric. Normalised to T=0, directly comparable across experiments.<\/p>\n<span class=\"bg-formula\">% Wound closure = (A\u2080 \u2212 A\u209c) \/ A\u2080 \u00d7 100\n\nWhere:\n  A\u2080 = wound area at T=0 (immediately after scratching)\n  A\u209c = wound area at time t<\/span>\n\n<h3>Migration rate (\u00b5m\/h)<\/h3>\n<p>Average velocity of the cell front moving into the wound. Calculated from wound width at two timepoints.<\/p>\n<span class=\"bg-formula\">Migration rate (\u00b5m\/h) = (W\u1d62 \u2212 Wf) \/ (2 \u00d7 t)\n\nWhere:\n  W\u1d62 = initial wound width (\u00b5m) at T=0\n  Wf = final wound width (\u00b5m) at time t\n  t  = duration of migration (hours)\n  \u00f72 = because both edges migrate simultaneously<\/span>\n\n<h3>t\u00bd gap closure<\/h3>\n<p>Time to reach 50% wound closure. Useful for comparing treatments with different maximum closure rates or plateau kinetics. Read directly from the % wound closure vs. time curve \u2014 or calculated automatically by zenCELL owl software.<\/p>\n\n<h3>Statistical analysis<\/h3>\n<ul>\n  <li><strong>Comparing two conditions at one timepoint:<\/strong> unpaired t-test<\/li>\n  <li><strong>Comparing two conditions across multiple timepoints:<\/strong> two-way ANOVA with Bonferroni correction<\/li>\n  <li><strong>Comparing migration rates:<\/strong> present as mean \u00b1 SD, n \u2265 3 independent experiments, \u2265 3 wells per condition<\/li>\n  <li><strong>Normalise within each experiment<\/strong> to account for day-to-day variation in scratch width<\/li>\n<\/ul>\n\n<!-- SECTION 6: MITOMYCIN C -->\n<h2 id=\"proliferation\">6. Migration vs. proliferation \u2014 when and how to use Mitomycin C<\/h2>\n\n<p>One of the most common questions in scratch assay experiments: <strong>is gap closure driven by cell migration, cell proliferation, or both?<\/strong><\/p>\n\n<p>In most adherent cell lines, gap closure involves both migration of cells from the wound edge and proliferation of cells behind the edge. Depending on your research question, you may need to separate these contributions.<\/p>\n\n<table class=\"bg-table\">\n  <tr><th>Scenario<\/th><th>Mitomycin C needed?<\/th><th>Reasoning<\/th><\/tr>\n  <tr><td>Short assay (&lt;12h) with slow-dividing cells<\/td><td class=\"bg-ok\">Optional<\/td><td>Proliferation contribution minimal in short timeframe<\/td><\/tr>\n  <tr><td>Long assay (&gt;24h) with fast-dividing cell lines<\/td><td class=\"bg-no\">Required<\/td><td>Proliferation significantly contributes to gap closure<\/td><\/tr>\n  <tr><td>Drug study affecting both migration and proliferation<\/td><td class=\"bg-no\">Required<\/td><td>Must isolate migration effect from antiproliferative effect<\/td><\/tr>\n  <tr><td>Pure migration study (e.g. chemokinesis)<\/td><td class=\"bg-no\">Required<\/td><td>Results must reflect motility only<\/td><\/tr>\n  <tr><td>Wound healing model (combined effect acceptable)<\/td><td class=\"bg-ok\">Not required<\/td><td>In vivo wound healing involves both \u2014 combined readout is biologically valid<\/td><\/tr>\n<\/table>\n\n<h3>Mitomycin C protocol<\/h3>\n<ul>\n  <li>Prepare stock solution: 10 mg\/mL in DMSO, store at -20\u00b0C, protect from light<\/li>\n  <li>Working concentration: 10 \u00b5g\/mL in complete medium<\/li>\n  <li>Pre-treatment: 2h before scratching at 37\u00b0C<\/li>\n  <li>Aspirate Mitomycin C medium, wash once with PBS, then create scratch and replace with fresh medium<\/li>\n  <li>Validate: run a parallel plate with BrdU or Ki67 staining at the end of the assay to confirm proliferation was blocked<\/li>\n<\/ul>\n\n<div class=\"bg-tip\">\n  <strong>zenCELL owl alternative to Mitomycin C<\/strong>\n  <p>With zenCELL owl, run unscratched reference wells in parallel in the same plate. Track confluence increase in these reference wells over time \u2014 this represents the proliferation component. Subtract from scratched well confluence change to isolate migration. This preserves cell health better than Mitomycin C treatment, which can have off-target effects.<\/p>\n<\/div>\n\n<!-- SECTION 7: TROUBLESHOOTING -->\n<h2 id=\"troubleshooting\">7. Scratch assay troubleshooting \u2014 the 6 most common problems<\/h2>\n\n<h3>Problem 1: Variable scratch width between wells or experiments<\/h3>\n<p><strong>Cause:<\/strong> Manual pipette tip scratching introduces \u00b130\u201360% width variability depending on operator, angle, pressure and speed. This makes inter-assay comparison unreliable and inflates standard deviation in migration rate calculations.<\/p>\n<p><strong>Solutions:<\/strong><\/p>\n<ul>\n  <li>Always use the same operator with the same technique<\/li>\n  <li>Use a straight-edge guide (ruler taped to the plate) for consistent scratch angle<\/li>\n  <li>Use the <a href=\"https:\/\/zencellowl.com\/scratchmaker\/\" style=\"color:var(--teal);text-decoration:none;font-weight:700;\">ScratchMaker stencil system<\/a> \u2014 reduces variability to &lt;5% without operator dependency<\/li>\n  <li>Normalise each well to its own T=0 area \u2014 reduces but does not eliminate the variability problem<\/li>\n<\/ul>\n\n<h3>Problem 2: Gap closes too quickly<\/h3>\n<p><strong>Causes:<\/strong> High serum concentration driving proliferation rather than migration; incorrect cell seeding density leading to residual cells in the gap; fast-migrating cell line for your assay duration.<\/p>\n<p><strong>Solutions:<\/strong> Reduce serum to 0.5\u20132%; add Mitomycin C (10 \u00b5g\/mL, 2h pre-treatment); widen the scratch using a larger tip; shorten the assay duration.<\/p>\n\n<h3>Problem 3: Cells detach at the scratch edge<\/h3>\n<p><strong>Causes:<\/strong> Too much pressure with the pipette tip; subconfluent monolayer (cells not anchored tightly to neighbours); inadequate plate coating.<\/p>\n<p><strong>Solutions:<\/strong> Ensure >95% confluence before scratching; reduce pipette tip pressure; coat wells with fibronectin (1 \u00b5g\/cm\u00b2, 1h at RT) or collagen I before seeding; switch to ScratchMaker to eliminate mechanical force on the cells.<\/p>\n\n<h3>Problem 4: ImageJ fails to detect wound edges<\/h3>\n<p><strong>Cause:<\/strong> Low contrast between the cell-free wound area and the cell monolayer \u2014 common with brightfield vs. phase contrast.<\/p>\n<p><strong>Solutions:<\/strong> Convert to 8-bit greyscale; enhance contrast (Image \u2192 Adjust \u2192 Brightness\/Contrast \u2192 Auto); increase threshold parameter in the Wound Healing Size Tool; switch to phase contrast imaging if available \u2014 gives better cell\/background contrast.<\/p>\n\n<h3>Problem 5: Results not reproducible between experiments<\/h3>\n<p><strong>Causes:<\/strong> Variable scratch width; different cell passage numbers; inconsistent imaging positions; manual timepoint sampling introducing variable delays.<\/p>\n<p><strong>Solutions:<\/strong> ScratchMaker for consistent gaps; zenCELL owl for automated imaging at fixed intervals from the same position every time; use cells from the same passage range across experiments (\u00b13 passages).<\/p>\n\n<h3>Problem 6: Scratch is curved, not straight<\/h3>\n<p><strong>Cause:<\/strong> Pipette tip tilted during scratch; not using a straight-edge guide.<\/p>\n<p><strong>Solution:<\/strong> Hold tip perpendicular to the plate (90\u00b0); use a straight-edge guide; use ScratchMaker precision channel guide.<\/p>\n\n<!-- SECTION 8: AUTOMATED -->\n<h2 id=\"automated\">8. Automated scratch assay \u2014 how zenCELL owl changes the workflow<\/h2>\n\n<p>The scratch assay is conceptually simple \u2014 but in practice, manual execution introduces reproducibility problems at two critical steps: <strong>gap creation<\/strong> (variable width) and <strong>imaging<\/strong> (incomplete kinetics, incubator disruption, operator time). zenCELL owl addresses the imaging problem; the ScratchMaker addresses the gap creation problem.<\/p>\n\n<table class=\"bg-table\">\n  <tr><th><\/th><th>Manual workflow<\/th><th>Automated (ScratchMaker + zenCELL owl)<\/th><\/tr>\n  <tr><td><strong>Gap width variability<\/strong><\/td><td class=\"bg-no\">\u00b130\u201360%<\/td><td class=\"bg-ok\">&lt;5%<\/td><\/tr>\n  <tr><td><strong>Imaging intervals<\/strong><\/td><td class=\"bg-no\">Every 4\u20138h \u2014 kinetics missing<\/td><td class=\"bg-ok\">Every 5 min \u2014 complete trace<\/td><\/tr>\n  <tr><td><strong>Conditions in parallel<\/strong><\/td><td class=\"bg-mid\">Limited by operator time<\/td><td class=\"bg-ok\">24 wells, identical conditions<\/td><\/tr>\n  <tr><td><strong>Incubator disruption<\/strong><\/td><td class=\"bg-no\">At every timepoint<\/td><td class=\"bg-ok\">Zero<\/td><\/tr>\n  <tr><td><strong>Analysis<\/strong><\/td><td class=\"bg-mid\">Manual ImageJ per image<\/td><td class=\"bg-ok\">Automatic per well, every timepoint<\/td><\/tr>\n  <tr><td><strong>Operator time (per experiment)<\/strong><\/td><td class=\"bg-no\">3\u20135h over 24h assay<\/td><td class=\"bg-ok\">~15 minutes setup only<\/td><\/tr>\n  <tr><td><strong>Data export<\/strong><\/td><td class=\"bg-mid\">Manual CSV after ImageJ<\/td><td class=\"bg-ok\">Direct CSV, PNG, AVI<\/td><\/tr>\n<\/table>\n\n<div class=\"bg-highlight\">\n  <p>zenCELL owl costs <strong>\u20ac14,000 one-time<\/strong> \u2014 no annual licence, no subscription. For a lab running 3 scratch assays per week, that is approximately <strong>\u20ac2 per assay<\/strong> over 2 years, with complete kinetic data, zero incubator disruption and no operator time at the microscope.<\/p>\n<\/div>\n\n<div class=\"bg-cta-inline\">\n  <p><strong>See the automated scratch assay workflow live.<\/strong> 30-minute remote demo \u2014 real cells, ScratchMaker and zenCELL owl running together inside an incubator.<\/p>\n  <a href=\"https:\/\/zencellowl.com\/live-remotedemo\/\" class=\"bg-btn\">Book your free demo<\/a>\n<\/div>\n\n<!-- RELATED -->\n<h2>Related pages<\/h2>\n<div class=\"bg-related\">\n  <a href=\"https:\/\/zencellowl.com\/wound-healing-assay\/\" class=\"bg-rel\">\n    <div class=\"bg-rel-tag\">Hub Page<\/div>\n    <h4>Wound Healing Assay \u2014 End-to-End Solution Overview<\/h4>\n  <\/a>\n  <a href=\"https:\/\/zencellowl.com\/scratchmaker\/\" class=\"bg-rel\">\n    <div class=\"bg-rel-tag\">Product<\/div>\n    <h4>ScratchMaker \u2014 Reproducible Gap Creation System<\/h4>\n  <\/a>\n  <a href=\"https:\/\/zencellowl.com\/scratch-assay\/\" class=\"bg-rel\">\n    <div class=\"bg-rel-tag\">Application<\/div>\n    <h4>Scratch Assay with zenCELL owl \u2014 Automated Imaging<\/h4>\n  <\/a>\n  <a href=\"https:\/\/zencellowl.com\/organoid-live-cell-imaging\/\" class=\"bg-rel\">\n    <div class=\"bg-rel-tag\">Related<\/div>\n    <h4>Organoid Live-Cell Imaging with zenCELL owl<\/h4>\n  <\/a>\n<\/div>\n\n<\/div><!-- \/bg -->\n\n<!-- SCHEMA -->\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"Article\",\n      \"headline\": \"Scratch Assay Protocol & ImageJ Analysis: The Complete Guide (2025)\",\n      \"description\": \"Complete step-by-step scratch assay protocol including cell seeding, gap creation, imaging, ImageJ Wound Healing Size Tool analysis, data interpretation, Mitomycin C guide and automated alternative with zenCELL owl.\",\n      \"author\": { \"@type\": \"Organization\", \"name\": \"zenCELL owl \/ innoME GmbH\" },\n      \"publisher\": { \"@type\": \"Organization\", \"name\": \"zenCELL owl\", \"url\": \"https:\/\/zencellowl.com\" },\n      \"datePublished\": \"2025-06-01\",\n      \"dateModified\": \"2025-06-27\"\n    },\n    {\n      \"@type\": \"HowTo\",\n      \"name\": \"Scratch Assay Protocol \u2014 Complete Step by Step\",\n      \"description\": \"How to perform a reproducible scratch assay (wound healing assay) from cell seeding to ImageJ analysis.\",\n      \"totalTime\": \"PT26H\",\n      \"step\": [\n        { \"@type\": \"HowToStep\", \"name\": \"Seed cells\", \"text\": \"Seed 100,000\u2013200,000 adherent cells per well in a 24-well plate in 500 \u00b5L\u20131 mL complete medium. Incubate at 37\u00b0C, 5% CO\u2082 overnight until >95% confluent.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Optional Mitomycin C pre-treatment\", \"text\": \"Add Mitomycin C (10 \u00b5g\/mL) 2h before scratching to block proliferation. Required for assays >12h or fast-cycling cell lines.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Create the scratch\", \"text\": \"Hold a P200 pipette tip perpendicular (90\u00b0) to the plate. Draw one straight continuous line without back-and-forth motion. Mark plate bottom for imaging reference.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Wash and replace medium\", \"text\": \"Aspirate medium, wash with PBS, replace with fresh medium \u00b1 compound at 0.5\u20132% serum. T=0 starts now.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Capture T=0 image\", \"text\": \"Image all wells within 15 minutes. This is the reference wound area for all calculations.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Monitor gap closure\", \"text\": \"Image every 4\u20138h manually, or every 5\u201330 min automatically with zenCELL owl, until control wells reach 80\u2013100% closure.\" },\n        { \"@type\": \"HowToStep\", \"name\": \"Analyse with ImageJ Wound Healing Size Tool\", \"text\": \"Open image in Fiji as 8-bit greyscale. Run Wound_healing_size_tool plugin. Export CSV. Calculate % wound closure = (A\u2080 \u2212 A\u209c)\/A\u2080 \u00d7 100. Or use zenCELL owl for fully automatic analysis.\" }\n      ]\n    },\n    {\n      \"@type\": \"FAQPage\",\n      \"mainEntity\": [\n        {\n          \"@type\": \"Question\",\n          \"name\": \"How do I analyse scratch assay images in ImageJ?\",\n          \"acceptedAnswer\": { \"@type\": \"Answer\", \"text\": \"Use the Wound Healing Size Tool plugin for ImageJ\/Fiji (Suarez-Arnedo et al., PLoS ONE 2020, 979 citations). Install the .ijm file into Fiji plugins folder, open your image in 8-bit greyscale, run the plugin. It automatically detects wound boundaries and calculates wound area, width and coverage. Export as CSV. Calculate % wound closure = (A\u2080 \u2212 A\u209c)\/A\u2080 \u00d7 100.\" }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"What is the best ImageJ plugin for wound healing assay analysis?\",\n          \"acceptedAnswer\": { \"@type\": \"Answer\", \"text\": \"The Wound Healing Size Tool (Suarez-Arnedo et al., PLoS ONE 2020) is the most widely used and cited (979\u00d7). It automatically detects wound edges using pixel intensity variance and runs in batch mode. Alternatives: MRI Wound Healing Tool for cell orientation analysis, CSMA (2025) for improved detection of cells migrating into the wound, TScratch for MATLAB-based processing.\" }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Do I need Mitomycin C in a scratch assay?\",\n          \"acceptedAnswer\": { \"@type\": \"Answer\", \"text\": \"For assays under 12h with slowly proliferating cells, Mitomycin C is optional. For assays over 12h, fast-cycling cell lines (HeLa, A549), or when studying drugs that also affect proliferation, add Mitomycin C (10 \u00b5g\/mL, 2h pre-treatment) to block cell division and ensure gap closure reflects migration only.\" }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"How do I calculate % wound closure from ImageJ results?\",\n          \"acceptedAnswer\": { \"@type\": \"Answer\", \"text\": \"% wound closure = (A\u2080 \u2212 A\u209c) \/ A\u2080 \u00d7 100, where A\u2080 is wound area at T=0 and A\u209c is wound area at time t. The Wound Healing Size Tool exports wound area values per image as CSV, which you then process in Excel or GraphPad Prism.\" }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Why is my scratch assay not reproducible?\",\n          \"acceptedAnswer\": { \"@type\": \"Answer\", \"text\": \"Manual pipette tip scratching introduces \u00b130\u201360% wound width variability between wells and operators. Solutions: use a straight-edge guide, same operator throughout, or the ScratchMaker stencil system which reduces variability to <5%. For imaging reproducibility, use zenCELL owl for automated imaging at fixed intervals from identical positions.\" }\n        }\n      ]\n    }\n  ]\n}\n<\/script>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Protocol Guide Migration Assay June 2025 \u00b7 Updated \u23f1 12 min read Scratch Assay Protocol &amp; ImageJ Analysis: The Complete Guide (2025) Everything you need to run a reproducible scratch [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-6683","post","type-post","status-publish","format-standard","hentry","category-allgemein"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Scratch Assay Protocol &amp; ImageJ Analysis: Complete Guide<\/title>\n<meta name=\"description\" content=\"Step-by-step scratch assay protocol + complete ImageJ Wound Healing Size Tool guide. 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