How to determine the concentration and storage of MCE inhibitors dissolved and packaged in DMSO after arrival?

For 5 mg powder, moisture-induced clumping is the biggest concern. Before opening, centrifuge first to let the powder settle to the bottom. Ideally, aliquot in a dry environment or a glovebox; at minimum, avoid opening the cap in humid weather, and add some desiccant. If you cannot use it all at once, do not repeatedly bring the original vial to room temperature and open it. Instead, plan to dissolve the entire amount at once and then aliquot; even if solubility allows, prepare a 10 mM stock solution and aliquot it. After dissolution, use a dry pipette tip when taking the stock solution, and seal the aliquot tubes tightly with Parafilm. If conditions permit, the original vial can be sealed after being filled with nitrogen, but for general cell experiments, proper aliquoting is sufficient.

I recommend long-term storage at -80 ℃. DMSO will freeze or become sticky at -20 ℃, and must be completely melted before use. Repeated heating increases the risk of water absorption and degradation. After packaging, try to use up each tube as much as possible. If it has to be repeated, control it within 3 times and avoid leaving it at room temperature for too long. You can reserve one tube for short-term storage at -20 ℃ or 4 ℃, and keep the rest at -80 ℃. When using, balance to room temperature before opening the lid. Do not open the lid at low temperatures to prevent condensed water from entering the mother liquor.

First, do not fix the formula at 1mL. Whether 5mg can be formulated as 10mM depends on the molecular weight. Calculate the DMSO volume according to the molecular weight on the COA and the actual weighing/labeling amount. Generally, the molecular weight of the kinase inhibitor is 400-600, and 5mg corresponds to about 0.8-1.2mL. It is recommended to dispense according to a single experimental dose. Cell experiments often use 10mM mother liquor to dilute to the working fluid. If you use 2-5μL at a time, divide it into 10-20μL/tube to avoid repeated use of the whole tube. Select a low adsorption cryopreservation tube during packaging to mark the concentration, batch number, and date, so as to avoid the actual concentration deviation caused by the liquid hanging on the wall.