Deionised water

Standard protocols described by Baruah and Barthakur [27 ] and AOAC 990.08 [28 ] specifications were used to determine the physicochemical parameters of only two samples with highest concentration of explosives contamination (NS2 sample for SITE1 and PS2 sample for SITE2). The concentration of explosives in all samples was detected as per U.S, EPA, 8330 methods [29 ]. Briefly, the soil samples were analyzed using LC-20, HPLC system (Shimadzu, Kyoto, Japan) equipped with Restek ultra C18 column (25 cm × 4.6 mm) (Restek, Bellefonte, PA, USA) and a UV-photodiode array detector (9926). The mobile phase consisted of 46% methanol (Merck, Darmstadt, Germany) and 54% deionised water (Merck, Germany) at 1 mL/min flow rate. The sample injection volume used was 10 µL with absorption detection at 254 nm. Samples quantification was performed using EPA certified RDX/HMX standards (Cat 31450; Restek, Bellefonte, PA, USA,) and known concentrations of RDX and HMX.

AFM analysis was performed as described previously [82 (link)]. Shortly, amyloid samples were prepared by applying a drop of 10 μL medium on freshly cleaved mica, V1 grade (NanoAndMore GmbH, Germany). After incubation for 10 min, the sample was rinsed with deionised water (Merck Millipore Inc., Burlington, MA, USA) and dried under a gentle stream of argon. A Multimode 8 Nanoscope atomic force microscope (AFM, Bruker, Billerica, MA, USA) was used to image the surfaces of the mica substrate and the deposited amyloid structures.