Department of Pharmaceutics, Vivekanand Education Society's College of Pharmacy, Hashu Advani Memorial Complex, Chembur, Mumabi-74, India.
Curr Drug Deliv. 2013 Aug;10(4):363-73. doi: 10.2174/1567201811310040001.
Microbubbles are small spherical gas filled bubbles in the size range of 1-10 microns. Their external coat is made of polymers or phospholipids. In combination with ultrasound, they have been explored as contrast agents for ultrasound and also carriers for drug and gene delivery. In response to ultrasound of lower mechanical index, microbubbles oscillate and vibrate to give a distinct signal in ultrasound imaging. At a higher mechanical index, these microbubbles rupture and break to deliver the drugs or genes enclosed in them or attached to their surface. The behaviour of microbubbles in response to ultrasound is a characteristic of the properties of microbubbles like its shell composition, shell thickness and the density and compressibility of the enclosed gas. Microbubbles have various applications in diagnostic imaging like echocardiography, and imaging of cancer cells, inflammed cells etc. They are also used as a medium for drug and gene delivery. Microbubbles can be further modified by binding specific ligands to their surface which specifically attach to certain cells so that selective action of the microbubbles can be seen at that location of cells.
微泡是一种大小在 1-10 微米范围内的球形充气小气泡。它们的外壳由聚合物或磷脂制成。结合超声，它们已被探索作为超声对比剂，以及药物和基因传递的载体。在较低机械指数的超声下，微泡会振动和振荡，在超声成像中产生明显的信号。在较高的机械指数下，这些微泡会破裂并释放出包裹在其中或附着在其表面的药物或基因。微泡对超声的响应行为是其特性的一个特征，如它的壳组成、壳厚度以及封闭气体的密度和可压缩性。微泡在诊断成像中有各种应用，如超声心动图和癌细胞、炎症细胞等的成像。它们也被用作药物和基因传递的媒介。微泡可以通过将特定配体结合到其表面进一步修饰，这些配体特异性地附着在某些细胞上，从而可以在细胞的那个位置观察到微泡的选择性作用。
