Joshua Mcbee
LCMS weirdo. Pretend expert in all things charged or separated. Biking aficionado, coffee enthusiast, destroyer of mass spectrometers.
- Here’s an interesting story for #teammassspec. Liraglutide went generic in December 2024 and we have been developing methods for impurity characterization but we kept seeing an unusual modification with a +12 Da shift. A little digging revealed that others had noticed that the n-terminal histidine..
- Was sensitive to formaldehyde and could cyclize and this was noticed with interaction to certain excipients. We developed a quick assay for monitoring this modification. But we wanted to see if Semaglutide was sensitive to this modification too. Sure enough, exposure to formaldehyde modified
- Semaglutide as well. With the explosion of compounding GLP-1s we wanted to see if improper handling would create this modification. We “obtained” a syringe of compounded Semaglutide and sure enough the modification shows up at about 1.5% relative to the FLP which exceeds FDA guidelines.
- We don’t know what the risk of this modification is but we tested Ozempic as well and it was well within the guidelines of manufacturing peptide drugs. Beware of these pharmacies offering “cheap” GLP-1s. You don’t always know what You are going to get. www.linkedin.com/posts/joshua...
- Dinner at Locust Point Steamers in Baltimore prior to #ASMS2025. Highly recommended for any seafood lovers coming to the conference!
- Catch-44
- Reposted by Joshua McbeeThis is perfect. Absolutely perfect.
- Cory Booker on the floor of the senate reconciling quantum mechanics and relativity.
- I am going to #USHUPO2025 next week. I’m super excited to connect with some old friends and have some conversations with everyone about all the latest tech! If you see me there, please tap me on the shoulder and say hello!
