Koneru Bhuvaneswari, Shi Yi, Wang Yu-Chieh, Chavala Sai H, Miller Michael L, Holbert Brittany, Conson Maricar, Ni Aiguo, Di Pasqua Anthony J
Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA.
North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA.
Molecules. 2015 Oct 30;20(11):19690-8. doi: 10.3390/molecules201119650.
Tetracycline (TC) is a well-known broad spectrum antibiotic, which is effective against many Gram positive and Gram negative bacteria. Controlled release nanoparticle formulations of TC have been reported, and could be beneficial for application in the treatment of periodontitis and dental bone infections. Furthermore, TC-controlled transcriptional regulation systems (Tet-on and Tet-off) are useful for controlling transgene expression in vitro and in vivo for biomedical research purposes; controlled TC release systems could be useful here, as well. Mesoporous silica nanomaterials (MSNs) are widely studied for drug delivery applications; Mobile crystalline material 41 (MCM-41), a type of MSN, has a mesoporous structure with pores forming channels in a hexagonal fashion. We prepared 41 ± 4 and 406 ± 55 nm MCM-41 mesoporous silica nanoparticles and loaded TC for controlled dug release; TC content in the TC-MCM-41 nanoparticles was 18.7% and 17.7% w/w, respectively. Release of TC from TC-MCM-41 nanoparticles was then measured in phosphate-buffered saline (PBS), pH 7.2, at 37 °C over a period of 5 h. Most antibiotic was released from both over this observation period; however, the majority of TC was released over the first hour. Efficacy of the TC-MCM-41 nanoparticles was then shown to be superior to free TC against Escherichia coli (E. coli) in culture over a 24 h period, while blank nanoparticles had no effect.
四环素（TC）是一种广为人知的广谱抗生素，对许多革兰氏阳性菌和革兰氏阴性菌都有效。已有关于TC控释纳米颗粒制剂的报道，其可能有助于牙周炎和牙骨感染的治疗。此外，TC调控转录系统（Tet-on和Tet-off）在生物医学研究中可用于在体外和体内控制转基因表达；控释TC系统在此处可能也有用。介孔二氧化硅纳米材料（MSNs）在药物递送应用方面受到广泛研究；移动晶体材料41（MCM-41）是MSN的一种，具有介孔结构，其孔以六边形方式形成通道。我们制备了粒径为41±4和406±55 nm的MCM-41介孔二氧化硅纳米颗粒并负载TC以实现药物控释；TC-MCM-41纳米颗粒中TC的含量分别为18.7%和17.7%（w/w）。然后在37℃下，于pH 7.2的磷酸盐缓冲盐水（PBS）中，对TC-MCM-41纳米颗粒中TC的释放进行了5小时的测定。在该观察期内，两种纳米颗粒中的大部分抗生素都已释放；然而，大部分TC在最初一小时内就已释放。在24小时的培养过程中，TC-MCM-41纳米颗粒对大肠杆菌的抗菌效果优于游离TC，而空白纳米颗粒则无作用。
