Ibrahim G F, Lyons M J, Walker R A, Fleet G H
J Clin Microbiol. 1985 Sep;22(3):361-5. doi: 10.1128/jcm.22.3.361-365.1985.
Several cultures of gram-negative and gram-positive bacteria were successfully immobilized with titanous hydroxide. The immobilization efficiency for the microorganisms investigated in saline and broth media ranged from 80.2 to 99.9%. The immobilization of salmonellae was effective over a wide pH range. The presence of buffers, particularly phosphate buffer, drastically reduced the immobilization rate. However, buffers may be added to immunoassay systems after immobilization of microorganisms. The immobilization process involved only one step, i.e., shaking 100 microliter of culture with 50 microliter of titanous hydroxide suspension in polystyrene tubes for only 10 min. The immobilized cells were so tenaciously bound that vigorous agitation for 24 h did not result in cell dissociation. The nonspecific binding of 125I-labeled antibody from rabbits and 125I-labeled protein A by titanous hydroxide was inhibited in the presence of 2% gelatin and amounted to only 5.6 and 3.9%, respectively. We conclude that this immobilization procedure is a potentially powerful tool which could be utilized in solid-phase immunoassays concerned with the diagnosis of microorganisms.
几种革兰氏阴性菌和革兰氏阳性菌培养物成功地用氢氧化钛固定。在盐水和肉汤培养基中所研究的微生物的固定效率为80.2%至99.9%。沙门氏菌在很宽的pH范围内都能有效固定。缓冲液的存在，尤其是磷酸盐缓冲液，会大幅降低固定率。然而，可在微生物固定后将缓冲液添加到免疫分析系统中。固定过程仅涉及一个步骤，即在聚苯乙烯管中将100微升培养物与50微升氢氧化钛悬浮液振荡10分钟。固定的细胞结合得非常牢固，剧烈搅拌24小时也不会导致细胞解离。在2%明胶存在下，氢氧化钛对兔125I标记抗体和125I标记蛋白A的非特异性结合受到抑制，分别仅为5.6%和3.9%。我们得出结论，这种固定方法是一种潜在的强大工具，可用于与微生物诊断相关的固相免疫分析。
