Using low dose x-ray speckle visibility spectroscopy to study dynamics of soft matter samples

We demonstrate the successful application of X-ray Speckle Visibility Spectroscopy (XSVS) experiments to study dynamics radiation sensitive, biological samples with unprecedentedly small doses 45 Gy and below. Using XSVS, we track casein micelles in native, concentrated, acidified solution conditions, while substantially reducing deposited dose as compared alternative techniques like sequential photon correlation spectroscopy (XPCS). The Brownian motion a skim milk sample yields hydrodynamic radius deviations from characteristic $q$-dependent diffusion coefficient $D(q)$ can be observed more concentrated conditions. low applied our allows observation static, frozen speckle patterns gelled acidic milk. show that XSVS technique is especially suitable for tracking sensitive combination improved coherent properties new generation sources, emphasizing great potential further investigations protein using fourth synchrotrons free electron lasers.