Surfactant and Colloid Group, Department of Chemistry, University of Hull, Cottingham Road, HU6 7RX Hull, United Kingdom.
J Am Chem Soc. 2013 Apr 10;135(14):5282-5. doi: 10.1021/ja400781f. Epub 2013 Mar 29.
We have developed a class of selective antimicrobial agents based on the recognition of the shape and size of the bacterial cells. These agents are anisotropic colloid particles fabricated as negative replicas of the target cells which involve templating of the cells with shells of inert material followed by their fragmentation. The cell shape recognition by such shell fragments is due to the increased area of surface contact between the cells and their matching shell fragments which resembles antibody-antigen interaction. We produced such "colloid antibodies" with photothermal mechanism for shape-selective killing of matching cells. This was achieved by the subsequent deposition of (i) gold nanoparticles (AuNPs) and (ii) silica shell over yeast cells, which were chosen as model pathogens. We demonstrated that fragments of these composite AuNP/silica shells act as "colloid antibodies" and can bind to yeast cells of the same shape and size and deliver AuNPs directly onto their surface. We showed that after laser irradiation, the localized heating around the AuNPs kills the microbial cells of matching shape. We confirmed the cell shape-specific killing by photothermal colloid antibodies in a mixture of two bacterial cultures of different cell shape and size. This approach opens a number of avenues for building powerful selective biocides based on combinations of colloid antibodies and cell-killing strategies which can be applied in new antibacterial therapies.
我们开发了一类基于对细菌细胞形状和大小识别的选择性抗菌剂。这些试剂是各向异性胶体颗粒，作为目标细胞的负复制品制造而成，涉及用惰性材料壳对细胞进行模板化，然后对其进行破碎。这种壳碎片对细胞形状的识别是由于细胞与其匹配的壳碎片之间的表面积接触增加，这类似于抗体-抗原相互作用。我们通过光热机制产生了这种具有形状选择性杀伤匹配细胞的“胶体抗体”。这是通过随后在酵母细胞上沉积（i）金纳米颗粒（AuNPs）和（ii）二氧化硅壳来实现的，酵母细胞被选为模型病原体。我们证明，这些复合 AuNP/二氧化硅壳的碎片可以作为“胶体抗体”，并与相同形状和大小的酵母细胞结合，并将 AuNPs 直接递送到它们的表面。我们证明，激光照射后，AuNPs 周围的局部加热会杀死具有匹配形状的微生物细胞。我们通过两种不同形状和大小的细菌培养物的混合物中的光热胶体抗体证实了细胞形状特异性杀伤。这种方法为基于胶体抗体和细胞杀伤策略的组合构建强大的选择性杀菌剂开辟了许多途径，可应用于新的抗菌疗法。
