Novel drug carriers capable of targeted and/or pH dependent release of biologically active agents into selected pH environments including the gastrointestinal (GI), ophthalmic, urinary, or reproductive tracts. Unexpectedly, carriers including free fatty acids (FFA) are able to deliver biologically active agents to various pH environments. Such targeted delivery is tailorable and useful for active agents that are: (a) injurious to the upper GI tract (esophagus, stomach, and duodenum), (b) acid labile, (c) impermeable/insoluble compounds in GI fluids, (d) susceptible to first pass metabolism, and/or (e) cause stomach irritation, upset, or dyspepsia.
                            新型药物载体能够有针对性地和/或根据 pH 值将
生物活性剂释放到选定的 pH 值环境中,包括胃肠道(GI)、眼科、泌尿道或生殖道。令人意想不到的是,包括游离
脂肪酸(FFA)在内的载体能够将
生物活性制剂输送到不同的 pH 环境中。这种有针对性的递送是可定制的,对以下活性制剂非常有用:(a) 对上消化道(食道、胃和十二指肠)有害,(b) 易变酸,(c) 在消化道液体中不渗透/不溶解,(d) 易发生首过代谢,和/或 (e) 引起胃刺激、不适或消化不良。