{"id":48925,"date":"2026-06-27T03:06:40","date_gmt":"2026-06-27T03:06:40","guid":{"rendered":"https:\/\/peptidepurityrank.com\/?p=48925"},"modified":"2026-06-27T03:00:05","modified_gmt":"2026-06-27T10:00:05","slug":"48925","status":"publish","type":"post","link":"https:\/\/peptidepurityrank.com\/48925\/","title":{"rendered":"Example 3 &#8211; Research &amp; Science"},"content":{"rendered":"\n<!-- ARTICLE STARTER -------------------------------------------------\n  In a NEW post: click + -> \"Custom HTML\" -> paste this -> edit the words.\n  Set a Featured image (post sidebar) = the cover used across the site.\n  Pick a Category (e.g. \"Lab Testing & COAs\"). To spotlight it on the\n  blog page, add the tag \"Top Picks\".\n  Then add two more blocks below this one: a Shortcode block with\n  [ppr_author] and another with [ppr_related].\n------------------------------------------------------------------- -->\n<div class=\"ppr ppr-post\">\n\n  <nav class=\"ppr-crumb\"><a href=\"\/blog\/\">Blog<\/a> &rarr; <span>Lab Testing &amp; COAs<\/span><\/nav>\n\n  <h1 class=\"ppr-s ppr-title\">How to Read a Janoshik COA &mdash; HPLC, Mass Spec &amp; the Numbers That Matter<\/h1>\n  <p class=\"ppr-dek\">A line-by-line walkthrough of a third-party certificate of analysis: what HPLC purity, net peptide content, and mass-spec identity actually prove.<\/p>\n\n  <div class=\"ppr-postby\">\n    <img decoding=\"async\" src=\"\/wp-content\/uploads\/harrison-peralta.jpg\" alt=\"Harrison Peralta\">\n    <span><strong>Harrison Peralta<\/strong> &middot; Updated Jun 22, 2026 &middot; 9 min read<\/span>\n  <\/div>\n\n  <div class=\"ppr-takeaways\">\n    <div class=\"lab\">The short answer<\/div>\n    <ul>\n      <li>A COA certifies three separate things &mdash; identity, purity, and how much actual peptide is in the vial. They are not the same number.<\/li>\n      <li>&#8220;99% HPLC purity&#8221; and &#8220;99% net peptide content&#8221; answer different questions. A vial can be highly pure and still light on peptide by mass.<\/li>\n      <li>A report is only as trustworthy as its chain of custody: a matching batch number, a recent test date, and a named, independently verifiable lab.<\/li>\n    <\/ul>\n  <\/div>\n\n  <h2 class=\"ppr-s\">What a COA certifies<\/h2>\n  <p>Every credible certificate of analysis answers three separate questions: what the compound is, how clean it is, and how much actual peptide you are paying for. Treat them as one number and you will overpay for the wrong thing.<\/p>\n\n  <div class=\"ppr-define\">\n    <div class=\"lab\">Definition &middot; Net peptide content<\/div>\n    <p>The share of a vial&#8217;s total mass that is actual peptide, once water, salts, and synthesis counter-ions are subtracted. A vial can be 99% pure by HPLC and still only 80% peptide by mass &mdash; purity and content are not the same claim.<\/p>\n  <\/div>\n\n  <h2 class=\"ppr-s\">Verify these five fields on every report<\/h2>\n  <ol class=\"ppr-ol\">\n    <li>The batch number on the report matches the batch printed on your vial.<\/li>\n    <li>The testing lab is named &mdash; and the report is verifiable on that lab&#8217;s own portal.<\/li>\n    <li>The test date is recent, not recycled from an older batch.<\/li>\n    <li>An HPLC chromatogram is included, showing a single dominant peak.<\/li>\n    <li>A mass-spec result confirms the observed mass equals the expected mass.<\/li>\n  <\/ol>\n\n  <h2 class=\"ppr-s\">Three numbers, three questions<\/h2>\n  <table class=\"ppr-table\">\n    <thead><tr><th>Test<\/th><th>What it answers<\/th><th>Good result<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td>HPLC purity<\/td><td>How clean is the peptide fraction?<\/td><td>&ge; 99% main peak<\/td><\/tr>\n      <tr><td>Net peptide content<\/td><td>How much peptide by mass?<\/td><td>Stated &amp; &ge; 80%<\/td><\/tr>\n      <tr><td>Mass spec<\/td><td>Is it the right molecule?<\/td><td>Observed = expected<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n\n  <div class=\"ppr-note\"><span>RESEARCH USE<\/span><p>A COA certifies what a material is &mdash; not that it is safe for any use. Nothing here is medical, dosing, or human-use guidance. Products are evaluated for laboratory research only.<\/p><\/div>\n\n  <h2 class=\"ppr-s\">Bottom line<\/h2>\n  <p>Read the header before the headline number. A recent, batch-matched report from a named, independently verifiable lab &mdash; showing high HPLC purity and a stated net peptide content &mdash; is worth far more than a bigger percentage you cannot trace to your vial.<\/p>\n\n<\/div>\n\n<!-- AEO \/ rich-result schema. Edit the Q&As to match this article. -->\n<script type=\"application\/ld+json\">\n{\n  \"@context\":\"https:\/\/schema.org\",\n  \"@type\":\"FAQPage\",\n  \"mainEntity\":[\n    {\"@type\":\"Question\",\"name\":\"What does a peptide COA actually prove?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A certificate of analysis certifies identity (mass spec), purity (HPLC), and net peptide content - three separate measures, not one.\"}},\n    {\"@type\":\"Question\",\"name\":\"Is 99% HPLC purity the same as 99% peptide?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. HPLC purity measures how clean the peptide fraction is; net peptide content measures how much of the vial's mass is actual peptide. A vial can be 99% pure and only 80% peptide by mass.\"}}\n  ]\n}\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Learn the latest studies and research findings<\/p>\n","protected":false},"author":1,"featured_media":47511,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[29],"tags":[10,26],"class_list":["post-48925","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-science","tag-featured","tag-top-picks"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Example 3 - Research &amp; Science - Peptide Purity Rankings<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/peptidepurityrank.com\/48925\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Example 3 - Research &amp; 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