{"podcast":{"title":"Concentrating on Chromatography","slug":"concentrating-on-chromatography-7157959","podcast_index_feed_id":7157959,"rss_url":"https://anchor.fm/s/fd632380/podcast/rss","website_url":"https://concentratingonchromatography.com","image_url":"https://d3t3ozftmdmh3i.cloudfront.net/staging/podcast_uploaded_nologo/42411328/42411328-1731191904094-fc5e6d90497be.jpg","author":"David Oliva","episode_count":62,"summary":"Dive into the frontiers of chromatography, mass spectrometry, and sample preparation with host David Oliva. Each episode features candid conversations with leading researchers, industry innovators, and passionate scientists who are shaping the future of analytical chemistry. From decoding PFAS detection challenges to exploring the latest in AI-assisted liquid chromatography, this show uncovers practical workflows, sustainability breakthroughs, and the real-world impact of separation science. Whether you’re a chromatographer, lab professional, or researcher you'll discover inspiring content!","last_synced_at":null,"page_url":"https://stenobird.com/podcast/concentrating-on-chromatography-7157959"},"episode":{"title":"Episode 48: Using LC-MS & GC-MS to Decode Photoredox Catalyst Stability","slug":"episode-48-using-lc-ms-gc-ms-to-decode-photoredox-catalyst-stability","published_at":"2026-02-17T12:00:00+00:00","page_url":"https://stenobird.com/podcast/concentrating-on-chromatography-7157959/episode-48-using-lc-ms-gc-ms-to-decode-photoredox-catalyst-stability","show_page_url":"https://stenobird.com/podcast/concentrating-on-chromatography-7157959","url":"https://podcasters.spotify.com/pod/show/chromatography/episodes/Episode-48-Using-LC-MS--GC-MS-to-Decode-Photoredox-Catalyst-Stability-e3f3ssr","audio_url":"https://anchor.fm/s/fd632380/podcast/play/115519835/https%3A%2F%2Fd3ctxlq1ktw2nl.cloudfront.net%2Fstaging%2F2026-1-15%2F418123099-44100-2-6b4e18fd41772.m4a","summary":"In this episode of Concentrating on Chromatography, we sit down with Lindsay Repka to discuss how LC-MS and GC-MS transformed her lab’s approach to photoredox chemistry.What began as a project to develop a visible-light photocrosslinking handle unexpectedly led to a major discovery: the solvent (DMF) was reacting with the photocatalyst itself. Using high-resolution LC-MS, Lindsay’s team observed multiple solvent adducts forming — sometimes with complete catalyst consumption. That discovery reshaped their research direction.Drawing from her ACS Northeast presentation and this in-depth conversation, Lindsay explains:🔬 How photoredox catalysts become activated under visible light📊 Why LC-MS was essential when NMR couldn’t resolve complex mixtures📈 How to design reproducible calibration curves for percent catalyst remaining📉 Why extracted ion chromatograms (EIC) outperform total ion chromatograms (TIC) at low concentrations⚗️ How solvent activation chemistry led to selective N-demethylation🧪 Why GC-MS with an internal standard streamlined reaction screening📐 What relative response factors mean — and why they can’t always be assumed constant🧑‍🔬 Practical tips for improving reproducibility (microbalances, deoxygenated solvents, temperature control)This episode is a rare deep dive into both LC-MS and GC-MS within the same research project, showing how chromatography-driven insight can turn unexpected degradation into productive new reactivity.If you work in:* Photoredox chemistry* Reaction optimization* Mass spectrometry method development* Catalyst screening* Academic synthetic chemistry…this conversation will resonate.🧪 Key Topics Covered* Photocatalyst stability in DMF, DCE, and MeCN* Demethylation under mild visible-light conditions* High-resolution Q-TOF LC-MS quantitati…","meta_description":"In this episode of Concentrating on Chromatography, we sit down with Lindsay Repka to discuss how LC-MS and GC-MS transformed her lab’s approach to photor…","key_points":[],"chapters":[],"topics":[],"duration_seconds":2103,"processing_state":"not_requested","actions":[{"name":"request_transcript","method":"POST","url":"https://stenobird.com/v1/public/podcasts/concentrating-on-chromatography-7157959/episodes/episode-48-using-lc-ms-gc-ms-to-decode-photoredox-catalyst-stability/transcription-requests","description":"Idempotently request low-priority transcript generation for this episode."},{"name":"read_markdown","method":"GET","url":"https://stenobird.com/podcast/concentrating-on-chromatography-7157959/episode-48-using-lc-ms-gc-ms-to-decode-photoredox-catalyst-stability.md","description":"Read the agent-friendly Markdown representation of this episode resource."}]}}