What happened?:
A mixture of imidazole (CAS: 288-32-4), 3′,5′-di-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine (CAS: 51549-35-0), and water was filtered through a pad of Celite using a fritted glass column typically used for flash column chromatography. The water insoluble 3′,5′-di-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine precipitated from solution and was collected on top of the Celite pad while the water soluble imidazole passed through the Celite pad. Positive pressure (compressed air) was used to accelerate the filtration process; positive pressure was achieved using "house" compressed air applied to the column with a Suba-Seal septum (24/40 size) pierced with a plastic syringe (1 mL). The combination of precipitated 3′,5′-di-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine and water-wetted Celite resulted in slow filtration with significant back-pressure. Increasing the pressure to accelerate the filtration caused the glass column to explode. All of the glass was contained within the fume hood. Most of the Celite/water/3′,5′-di-O-(tert-butyldimethylsilyl)-2′-deoxyguanosine/imidazole mixture was contained in the fume hood; the remaining material collected on the researchers' lab coats, safety glasses, and long pants. Both researchers immediately washed their hands and faces with soap and water. One researcher went home to shower while the other changed their clothes. Neither researcher sustained injuries. In the future, this filtration will be performed under negative pressure (i.e., using a Buchner funnel and house vacuum) to avoid over-pressurization.