N 2 hydroxyethylpiperazine n 2 ethanesulphonic acid hepes buffer

Hydrogen tetrachloroaurate(III) trihydrate (chloroauric acid, HAuCl₄·3H₂O) was purchased from Fisher Chemical, Ireland. N-2-hydroxyethylpiperazine-N-2-ethanesulphonic acid (HEPES) buffer was purchased from Hampton Research, US. Sodium phosphate monobasic (NaH₂PO₄) and disodium hydrogen phosphate (Na₂HPO₄) were purchased from Sigma Aldrich, Ireland. Deionized water, deionized using Elix® Reference Water Purification System from Millipore, Ireland, was used for all experiments and solution preparations.

Hydrogen tetrachloroaurate(III) trihydrate (HAuCl₄·3H₂O) was purchased from Fisher Chemical, Ireland. The N-2-hydroxyethylpiperazine-N-2-ethanesulphonic acid (HEPES) buffer was purchased from Hampton Research (Aliso Viejo, CA, USA). Sodium hydroxide (NaOH), hydrochloride acid (HCl), sodium phosphate monobasic (NaH₂PO₄), and disodium hydrogen phosphate (Na₂HPO₄) were purchased from Sigma Aldrich (Arklow, Ireland). Aspergillus niger ATCC 16404, Mucor hiemalis LZB 130, and Penicillium chrysogenum LZB 141 strains were purchased from Blades Biological Ltd. (Kent, UK). Potato dextrose agar (PDA) was purchased from Lab M (Lancashire, UK).
Sterilised deionised water, deionised using Elix^® Reference Water Purification System from Millipore (Cork, Ireland), and sterilised using Autoclave SX-500E from Mason Technology (Dublin, Ireland), was used for all experiments and solution preparations.