My PBS buffer won't dissolve

This is likely the answer. You’re Ca salts are likely falling out of solution due to pH. Moreover, I’ve never heard of adding Ca or Mg salts into a PBS buffer..More

Thank you!! I'll try this first thing on Monday! Do you think I could use the solution I made today or should I make a new one then? It is in RT now, covered ofc.More

Thanks! How high temperature should I use? I tried at 65°C but it didn't do much unfortunately :(More

Thanks! At the first time it was stirring for like 3 hours while I was doing other things (today I didn't have that much time) but I could definitely try to leave it stirring for a longer period on Monday!More

And here's the recipe: 100ml of 10x PBS 8,0 g NaCl 0,2 g KCl 1,44 g Na2HPO4 0,24 g KH2PO4 0,133 g CaCl • 2 H2O 0,10 g MgCl2 • 6 H2O to 100 ml UP H2O (first use ~80 ml, adjust pH, then add the rest - use volumetric flask)More

Thank you! Oh, I will try the water first next time! I was actually wondering if the order of adding things could be wrong, but then forgot the thought when I went back. If you have time, could you explain why it'd be better to add the salts to the water and not the other way round? I feel like I could better apply this to other situations too if I fully understood what the reason is!More

Thank you! I will try this if the other measures fail! Due to Uni's summer break we have less autoclaving opportunities than usually (only once or twice a week), hence the filtering, but if it comes down to this, I'll definitely do it. In normal circumstances this would be a really good idea!More