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Protein microcrystals of less than 10 µm in size are now applicable to X-ray studies by synchrotron microbeam technology. However, because of their small size, they are difficult to handle and mount. In addition, the deterioration of data quality by scattering from the mounting apparatus and crystallization solvent is not negligible. To address these issues, a simple mounting method is proposed using a fine-needle capillary similar to that used for microinjection in cell biology. In this method, microcrystals are pulled up by capillary action or pipetting, and are held at the tip together with a small amount of cryoprotectant. The quality of the diffraction data using this method is comparable to that of data from conventional cryoloops. This solid apparatus is hopefully suitable for automation of microcrystal handling coupled with optical tweezers.

A new and simple idea for scanning differential-phase-contrast (S-DPC) hard X-ray microscopy has been proposed. It only uses a wedge absorber coupled with two intensity detectors, and is much more sensitive to sample structures than absorption contrast. It can also extract pure quantitative one-dimensional phase gradient given by a sample without an effect of sample absorption. The S-DPC microscope has been constructed at BL24XU of SPring-8, and its feasibility has been successfully demonstrated at the photon energy of 10 keV by clearly visualizing structures of samples. Further, the experimental phase gradient profile agrees well with simulation. By integrating the resultant phase gradient, the corresponding phase shift distribution could be also imaged.

With the aim towards high-spatial-resolution phase measurement, a novel hard X-ray micro-interferometer using an imaging microscope has been proposed and constructed at Hyogo-BL of SPring-8. It is a wavefront-division-type interferometer consisting of a twin zone plate arranged in the same plane. We have succeeded in producing good interference fringes with a visibility of as high as 60% at the photon energy of 9 keV. The fringe scanning method was applied to retrieve phase-shift distribution of a sample. The phase-shift distribution of a 75-µm-thick kapton film and polystyrene microparticles could be imaged clearly with a spatial resolution of 160 nm and the obtained phase shift agreed well with the expected value.

Seven beamlines are operated for macromolecular crystallography (MX) at SPring‐8. The three undulator beamlines are developed for cutting edge target and four bending‐magnet beamlines are developed for high throughput MX. The undulator beamline, BL41XU that provides the most brilliant beam, is dedicated to obtain high quality data even from small‐size and weakly‐diffracting crystals. The minimum beam size at sample position is achieved to 10 μm diameter using a pin‐hole collimator. Its photon flux at wavelength λ = 1.0 A is 2.8×1011 photons/sec. This small beam coupled with irradiation point scanning method is quite useful to take diffraction dataset from small crystals by suppressing the radiation damage. These advanced technologies made a number of difficult protein structure analysis possible, (i.e. Sodium‐potassium ATPase). The bending‐magnet beamlines BL26B1/B2 and BL38B1 provide automatic data collection exploiting the high mobility of the beam. The beamline operation software “BSS,” sample auto‐cha...

We have developed a high‐resolution x‐ray microdiffraction system at the BL24XU of the SPring‐8. This system uses a focused beam produced by using a zone plate combined with a narrow slit. The size of the focused beam is 0.32 μm vertically and 1.3 μm horizontally and the angular divergence in the horizontal direction is about 70 μrad at a photon energy of 15 keV. This low‐divergence microbeam enables us to perform high‐resolution x‐ray microdiffraction experiments using a precise θ‐2θ goniometer with sub‐100‐nm‐resolved XYZ sample positioning stages. We demonstrate that the spatial non‐uniformity of the strain and the period in InGaAsP multi‐quantum‐well structures, fabricated by selective metalorganic‐vapor‐phase epitaxy, can be measured with sufficient accuracy using this system.