S1

Supporting Information

Photothermal Antibacterial and Antibiofilm

Activity of Black Phosphorus/Gold

Nanocomposites against a Pathogen Bacteria

İlknur Aksoya, Hüseyin Küçükkeçecib, Fatih Sevgic, Önder Metinb,*, Imren Hatay Patira,*

a Department of Biotechnology, Selcuk University, 42031, Konya, Turkey.

b Department of Chemistry, College of Sciences, Koç University, 34450, Istanbul, Turkey.

c Vocational School of Health Services, Department of Medical Services and Techniques,

Selcuk University, 42031, Konya, Turkey.

e-mail: ometin@ku.edu.tr; imrenhatay@gmail.com

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Figure S1. Raman spectra of as-synthesised BP crystals.

Figure S2. (a) Time-resolved emission spectra of bare BP and BP/Au nanocomposites and (b) a table showing the

lifetimes (τi) and amplitudes (Ai) of the lifetime decays of BP and BP/Au nanocomposites.

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Figure S3. Concentration (µg ml-1) of BP nanosheets (a) and BP/Au nanocomposites (b) dependent absorbance

graphs. (a) a: bacteria, b: NIR light, c: BP (32 µg ml-1) + NIR light, d: BP (64 µg ml-1) + NIR light, e: BP (128 µg ml-1) + NIR light. (b) a: bacteria, b: NIR light, c: BP/Au (32 µg ml-1) + NIR light, d: BP/Au (64 µg ml-1) +

NIR light, e: BP/Au (128 µg ml-1) + NIR light.

Figure S4. SEM images of (a) the untreated E. faecalis (blank) and (b) after the treatment of BP/Au

nanocomposites (128 µg ml-1) under NIR light irradiation. Scale bars are 200 nm.

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Figure S5. GSH depletion after different treatments at the concentration of 128 µg ml-1. The loss of GSH levels

(%) of H2O2, BP, BP/Au, BP/NIR and BP/Au/NIR are 79, 11, 19, 27 and 28, respectively.

Figure S6. Standard curve of GSH. The absorbance of each solution was measured at 405 nm. Residual GSH

concentration levels were measured according to the equation y= 0,0062x – 0,0233. X axis is concentration, y

axis is absorbance.

y = 0.0062x - 0.0233R² = 0.9987

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0 10 20 30 40 50 60 70 80 90 100

Ab

sorb

ance

Concentration (µM )

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Table S1. A table showing the previous studies about antibiofilm activity of 2D nanomaterials against various

microorganisms including E. faecalis with the biofilm inhibition percentage and suggested inhibition mechanisms.

Nanomaterial Concentrati

on (µg/ml)

Bacteria

tested

Biofilm

inhibition/eradication

(%)

Suggested mechanism Ref

GO

nanosheets

100 E. coli and P.

aeruginosa

~50% Cell membrane disruption 1

Graphene

nanoplatelets

- S. mutans 56% Mechanical damage of

cell wall

2

GO, GO-Tob

and GO-

Tob@CuS

100 S. aureus and

P. aeruginosa

20%, 50% and 80% Nano-knife, temperature

increase and ROS.

3

g-C3N4 - S. epidermidis - ROS generation 4

Ag/g-C3N4 200 S. aureus 70% ROS generation 5

MoS2

nanosheets

30 MRSA ~70% ROS-independent

oxidative stress and

membrane depolarization

6

TiO2 and Ag-

TiO2

composite

- E. coli and S.

aureus

56% and 77% for E.

coli

43% and 67% for S.

aureus

Disruption of membrane

integrity and

photocatalytic activity

7

NanoZnO/Ze 10.000 E. faecalis 85,2% Repression of a gene

associated with biofilm

formation

8

Au

nanoparticles

20 C. albicans < 1% Photodynamic therapy 9

BP/Au

nanocomposi

tes

64 E. faecalis 58 % Photothermal effect,

oxidative stress and

physical membrane

damage

This

work

References

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S6

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