A Malvern Zetasizer Nano (Malvern Panalytical Ltd.) was used to determine the hydrodynamic diameter and zeta potential of the nanoparticles. A Thermo Scientific Nicolet 6700 FTIR instrument fitted with a Smart iTR diamond ATR fixture was used to determine the FTIR spectra of the nanoparticles. A Genesys 150 UV/VIS Spectrophotometer (Thermo Fisher Scientific, Inc.) was used to evaluate the absorbance of FAM-peptide and a NanoSight LM10-HSB/GFT14 (Malvern Panalytical Ltd.) was used to determine the concentration of pSiNPs to calculate the number of peptides conjugated per pSiNP. For degradation studies, 0.5 mg/mL of lysozyme-loaded pSiNPs surface modified with PEG and CAQK were incubated in PBS at 37 °C. At 0, 12, 24, and 48 hours, aliquots of degraded nanoparticles were removed from the stock, pelleted, and resuspended into ethanol and loaded onto 42 μm formvar/carbon 400 mesh copper grids (Ted Pella, Inc.) and dried. The stock nanoparticles were similarly pelleted at each timepoint and resuspended in fresh PBS to ensure that degradation would not be stalled by the solubility of silicic acid in the supernatant.29 (link) TEM images were obtained on a JEOL 1400 plus electron microscope (JEOL USA, Inc.) operated at 80KeV and equipped with a Gatan Oneview camera (Gatan, Inc.).