実験報告書様式（一般利用課題・成果公開利用）（ ※本報告書は英語で記述してください。ただし、産業利用課題として採択されている方は日本語で記述していただいても結構です。 ）提出日 Date of Report

Experimental Report

2012/08/09

課題番号 Project No.

装置責任者 Name of responsible person

2012A0082
実験課題名 Title of experimentJ. Suzuki
Nano-Structural Analysis ofMulti-Sugar type Amphiphilic Oligomer Aggregates

装置名 Name of Instrument/（BL No.）
TAIKAN / BL15

実験責任者名 Name of principal investigator

実施日 Date of Experiment
2012/06/08 10:00 ～Tomokazu Yoshimura
所属 Affiliation

2012/06/11 10:00

Nara Women’s University
試料、実験方法、利用の結果得られた主なデータ、考察、結論等を、記述して下さい。（適宜、図表添付のこと）
Please report your samples, experimental method and results, discussion and conclusions. Please add figures andtables for better explanation.
1. 試料 Name of sample(s) and chemical formula, or compositions including physical form.

Recently we synthesized novel amphiphilic multi-sugar type oligomers(C12-mGEMA, m: polymerization degree) with dodecyl chain in terminal groupand multi-sugar chains [1]. Figure 1 shows the chemical structure of theC12-mGEMA. By employing surface tension measurements, C12-mGEMA wasshown to have a higher efficiency in lowering the surface tension of water. In
this study, by using small-angle neutron scattering (SANS), we investigated themeso-scale aggregate behavior of the C12-mGEMA in aqueous solution withvarying polymerization degree from 3.0 to 7.1.

Figure 1.

2. 実験方法及び結果 （実験がうまくいかなかった場合、その理由を記述してください。）
Experimental method and results.

If you failed to conduct experiment as planned, please describe reasons.

Experimental:
Amphiphilic multi-sugar type oligomer (C12-mGEMA) solutions were prepared by dissolving
the C12-mGEMA lyophilized powder of 25 mg/ml in pure D2O (Cambridge Isotope Laboratories,Inc.). SANS experiments were performed using the small-angle neutron scattering instrument(TAIKAN) installed at BL15 line at spallation neutrons source, MLF at the J-PARC, Tokai, Japan.
The total covered Q range is 0.015 – 3.0 Å-1. All SANS measurements were performed at ambient
temperature. The exposure time for each sample was 3 hours.
Results and Discussion:
Figure 2 shows SANS profiles for C12-mGEMA in aqueous solutions as a function ofpolymerization degree (m). The present SANS profiles were obtained by a part of small-angle
detector bank at L2 = 5.56 m. By using the Guinier equation, we estimated the radius of gyration(Rg). The Rg values were estimated to be 17.86 ± 0.14 Å for 3.0GEMA, 18.07 ± 0.15 Å for1

2. 実験方法及び結果（つづき） Experimental method and results (continued)

4.0GEMA, 21.16 ± 0.24 Å for 5.1GEMA, 26.91 ± 0.69 Å for 7.1GEMA, respectively. The Rgvalues were increased with increase in the polymerization degree. At the Q region beyond theGuinier region (QRg < 1), the SANS profile shows a power law behavior defined as I(Q) ~ Q-a.
According to literature [2], the a-value is becomes larger with increasing axial ratio. The a value
were estimated to be -4.07 for 3.0GEMA, -3.95 for 4.0GEMA, -2.90 for 5.1GEMA, -1.96 for
7.1GEMA, respectively. The SANS results suggested that aggregates formed by 3.0GEMA and4.0GEMA are spherical particles (globular micelles), and with increasing the polymerization
degree, the C12-mGEMA aggregates become from globular micelles to non-globular micelles, i.e.,
ellipsoidal micelles. In order to determine the shape of these micelles quantitatively, the model
analysis is now in progress.
References[1] Yoshimura et al., in preparation[2] Kratky, O.; Pilz, I. Q. Rev. Biophys. 1972, 5, 481.

Figure 2. SANS profile for amphiphilic multi-sugar typeoligomers (C12-mGEMA) in aqueous solutions as afunction of polymerization degree. Each profile is verticallyshifted to avoid overlapping.

2