A1 resonant scanning confocal microscope

The samples for TEM were prepared by dropping 5 μL of the DCPNs emulsion onto Formvar Film on 300 Square Mesh, Nickel Grids (EMS FF300-Ni). The TEM images were taken on a JOEL 2000FX TEM instrument at an acceleration voltage of 200 kV. DLS measurements were performed on a Malvern NanoZS apparatus operating at a 173-degree scattering angle. The CSLM experiments both for the DCPNs morphology and their penetration into biofilms were performed on a Nikon A1 Resonant scanning confocal microscope. SEM was carried out according to modified procedure.[²³ ] 2 ml 0.1 OD (10⁸ CFU mL⁻¹) bacterial suspension in M9 media was incubated with 4 v/v% DCPNs at 37 °C for 3 h. The bacteria were collected by centrifugation at 1,200 rpm for 10 min and washed twice using PBS (pH=7.4), and then made a thin smear on a silica wafer. Glutaraldehyde solution (2.5 % in PBS) was used to fix the bacteria cells at 4 °C overnight. After rinsing three times using PBS, the samples were dehydrated by ethanol in a gradient alcohol concentration (25 %, 50 %, 75 %, 90 %, and 100 %). Finally, after sputter coating with gold for 1 min, the samples were observed in FEI Magellan 400 field emission scanning electron microscope operated at 1 kV with 13 μA of beam current. Control samples without treatment were also prepared and tested in the same way as mentioned above.