PROBLEM TO BE SOLVED: To solve a problem that a conventional liposome containing silicon naphthalocyanine should be encapsulated in condition where dyes are dispersing, to be used in photodynamic therapy is low in dye-containing rate and also is low in a photoacoustic signal.SOLUTION: According to a lipid particle containing silicon naphthalocyanine analog, wherein ratio A/B of absorption coefficient A in first absorption maximum and absorption coefficient B in second absorption maximum in 700 nm to 800 nm is 5.0 or less, it is possible that the dye-containing rate in the lipid particle is increased and thereby intensity of a photoacoustic signal is improved.COPYRIGHT: (C)2015,JPO&INPIT【課題】従来のシリコンナフタロシアニン含有リポソームは、光線力学療法に用いるため色素が分散した状態で内包する必要があり、色素含有率が低く光音響信号も低かった。【解決手段】700nmから800nmでの第一の吸収極大における吸収係数Aと第二の吸収極大における吸収係数Bの比率A/Bが5.0以下であってシリコンナフタロシアニン類縁体を含有した脂質粒子によれば、脂質粒子内の色素含有率を上げ、光音響信号強度を向上させることが可能となる。【選択図】なし
