Experimental materials and instruments
Synthesis of isothiocyanate-benzensulfonamide
Synthesis of N-pep
Synthesis of pepABS
2-Naphthaleneacetic acid-(d)-Phe-(d)-Phe-(d)-Lys-(benzenesulfonamide)-OH
TEM sample preparation
CD spectrum
Analysis of intra-/extracellular accumulations of N-pepABS nanofibers
Cell cultures
CCK-8 assay
Western blots
Immunofluorescence
Transwell assay
Transfections
SEM images for treated cancer cells
TEM images for treated cancer cells
Flow cytometry
Real-time polymerase chain reaction
Animal experiments
Statistical analysis
A 0.75 wt % solution of N-pepABS was prepared by dissolving 7.5 mg of N-pepABS in 1 ml of ddH2O and adjusting the pH value around 10 with 1 M NaOH. It was sonicated to make a clear solution and monitored by pH paper, and then, the value of pH was decreased to 6.5 slowly by adding 1 M HCl and subsequently formed hydrogel. To see the difference of nanofiber morphology and hydrogel strength, another fraction of hydrogel was prepared in a similar way but with a final pH value of 5.5. The similar procedure was followed for the preparations of pepABS, ABS, and N-pep for testing their gelation abilities.