A group from University of Vienna, Faculty of Life Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, Vienna, Austria, etc.has reported about human serum albumin (HSA) nanoparticles conjugated with WGA for targeted delivery of antibiotics to combat urinary tract infections.
It is so interesting to learn how NPs were prepared. For the production of NPs, 20 mg HSA was dissolved in 10 ml 100 mM phosphate buffer pH 8. Afterwards, 1 ml olive oil was layered over the aqueous protein solution. The probe micro tip of the sonifier was positioned at the interface of the two phases. The sample was sonicated with an acoustic power of ≈253 W cm−2 at 40 % amplitude for 2 min. Subsequently the NPs were washed four times by centrifugation (5204 ×g, 40 min, 4 °C). For production of active pharmaceutical ingredients (API) containing NPs, 2.5 mg, 5 mg, 10 mg or 20 mg rifampicin (RIF) was dissolved in 1 ml isopropyl alcohol, mixed with olive oil and treated as described above. For the preparation of trimethoprim (TMP) loaded particles, 2.5 mg, 5 mg, 10 mg or 20 mg API was dissolved in 10 ml 100 mM phosphate buffer pH 8.
When human urothelial cells were incubated with targeted NPs, NPs (stained with green dyes) were observed around the blue stained nucleus and within the red stained membrane, which indicates an effective internalization of the NPs into the cells. Comparing the cases between with WGA and without WGA, 60 % higher cell binding potential was observed with WGA.