File Name : figure s1 with 600dpi.tif

Caption : figure s1. structural characterization of hsf and hhf in dry state: a.  bright field tem (bf-tem) image and the corresponding saed inset of hsf:  saed pattern of hsf collected from the represented area indicates different d spacings of 3.1, 2.7, 2.2, 1.9, 1.5 and 1.4 å representing crystal structures with different family of planes: g(020)/m(220), h(104), fh(112) or  h(113), fh(113), h(108), and h(300), respectively.6 b. bf-tem image and the corresponding saed inset of hhf:  saed pattern of hhf collected from the represented area indicates different d spacings of 2.7, 1.9, 1.5, 1.3 and 1.2 å representing crystal structures with different family of planes: h(104), fh(113), h(018), h(1010) and h(220), respectively. red, yellow and blue color represents feooh, hematite (h) and ferrihydrite (fh), respectively (scale bars of the tem image in figure a and b: 10nm) 

File Name : figure s2_with 600dpi.tif

Caption : figure s2. chemical characterization of hsf in wet and dry state: a. stem-eels shows the comparison of fe l2,3 edges in hsf iron cores in wet and dry condition. b. relative area integral ratio of l3:l2 fe edges in both wet and dry hsfs. the lower ratios in hsf (4.14 + 0.06) in dry state as compared to hsf (4.24+ 0.06) in wet state indicates the presence of fe+3 in higher quantities in wet state as compared to dry ferritins (n=3 for both the kind of analysis)  

File Name : figure s3_with 600dpi.tif

Caption : figure s3: time series tem images liquid encapsulation within the glcs and bubble formation in liquid. the formation of bubbles is controlled by the electron dose rate. the bubbles grow with higher electron dose rate as observed in figure s3-b and c

File Name : figure s4_with 600dpi.tif

Caption : figure s4: evidence of water presence in the liquid pockets of glc. a. haadf-stem image of water in glc. the dark circular areas indicated by the red arrows are the bubbles formed because of electron beam irradiation during eels acquisition. the white color square indicates the region of interest from which the eels low loss spectrum was acquired. scale bar is 50 nm. b. low-loss eels spectrum of water in glc.  the first peak at 5ev indicates the π π*  transition of the graphene layer.9 the second peak at 9 ev indicates the presence of water.10 the third peak at 33 ev indicates the π+ σ plasmon of graphene.11

File Name : figure s5_with 600dpi.tif

Caption : figure s5:  the integrity of glc after chemical characterization. a. the haadf-stem image acquired from the glc area before the eels acquisition. the contrast in the image is due to the bubble formation and the liquid area contributes to the brightness in the image. b. the haadf-stem image with the selected area (white color box) from where the eels spectrum was acquired. inset in figure b shows the average low loss signal collected from the selected area. the arrows at 5, 9 and 33 ev indicate the presence of graphene (π  π*) transition, the hydrogen gas bubble formed as a radiolysis product, and (π σ) plasmon of graphene, respectively (as also shown in figure s4).  c. the haadf-stem image collected from the same area after eels acquisition indicates that the integrity of graphene liquid cell is maintained even after the chemical characterization.