With the advent of technology, newer forms of drugs, such as proteins, DNA, and RNA, have entered mainstream product development. However, systemic delivery of macromolecules is limited by rapid blood clearance, poor stability in vivo, and inadequate uptake by cells. Nanoparticle (NP)-based delivery systems have emerged as suitable carriers for overcoming such pharmacokinetic limitations of macromolecule delivery. Nanocarriers, such as liposomes, provide protection for sensitive drug materials and also enhance the circulation half-life of therapeutics. Nanocarriers have also been shown to promote cellular uptake and the release of intact macromolecules in the cell. Besides liposomes, other nanocarriers, such as gold and iron oxide NPs, are also now being tested in clinical trials.

随着技术的出现，蛋白质，DNA和RNA等新形式的药物已进入主流产品开发。但是，大分子的全身递送受到血液快速清除，体内稳定性差以及细胞摄取不足的限制。基于纳米颗粒（NP）的递送系统已经作为克服上述大分子递送的药代动力学限制的合适载体而出现。纳米载体（例如脂质体）为敏感的药物材料提供保护，还可以延长治疗剂的循环半衰期。纳米载体也已显示出促进细胞摄取和完整大分子在细胞中的释放。除脂质体外，其他纳米载体，例如金和氧化铁NP，也正在临床试验中进行测试。