Small-angle X-ray and neutron scattering (SAXS/SANS) have proven to be powerful tools for characterizing hierarchical structures in biological and biomimetic material systems. Compared to alternative characterization techniques, these scattering methodologies exhibit three distinctive advantages in biomaterials research: (1) multi-scale structural resolution spanning six orders of magnitude (from ~1 Å to 10 μm when combined with wide-angle scattering and ultra-small-angle scattering techniques), (2) compatibility with in situ environmental controls (including temperature, pressure, humidity, tensil and electromagnetic field modulation), and (3) inherent non-destructive measurement capabilities that enable multimodal experimental approaches. This review systematically examines SAXS/SANS methodologies for probing static architectures and dynamic structural transitions in biomaterials. Representative case studies demonstrate the techniques' sensitivity to environmental stimuli such as thermal fluctuations, hygroscopic responses, uniaxial tensile stress, and shear-induced deformations [1-6]. We further discuss specialized sample environment design considerations for implementing these characterization protocols. Key findings include: (1) quantitative correlation between characteristic scattering signatures and mesoscopic structural features, (2) real-time monitoring of structural phase transitions through time-resolved intensity variations, (3) identification of microphase separation dynamics during material processing, and (4) emergence of anisotropic scattering patterns under mechanical deformation. These collective results establish SAXS/SANS as an indispensable multiscale characterization platform for advancing biomaterials innovation.

References
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