Richards R M, Xing J Z, Mackay K M
School of Pharmacy, Robert Gordon University, Schoolhill, Aberdeen, United Kingdom.
Pharm Res. 1996 Aug;13(8):1258-64. doi: 10.1023/a:1016084824877.
The purpose of the investigation was to determine the effect of tablet excipients on the activity of cetylpyridinium chloride (CPC) and the relative interaction between excipients and CPC.
An analytical assay was developed to evaluate the interaction between CPC and the excipients. In vivo activity was investigated using six volunteers by determining the reduction in colony forming units recoverable from the oropharynx after sucking each proprietary lozenge separately on different days. In vitro determinations investigated the relative antimicrobial activity of aqueous solutions of the lozenges and, the effect of pH and tablet base excipients on that activity against Staphylococcus aureus, Streptococcus pyogenes and Candida albicans.
Both in vivo and in vitro results showed that the tablet based lozenges had markedly reduced antimicrobial activities compared with previous results with a candy based lozenge (in vivo and in vitro) or the same concentration of aqueous CPC (in vitro). Magnesium stearate suspensions in CPC 250 micrograms/ml indicated that magnesium stearate adsorbed CPC and at 0.4% lozenge weight and above significantly reduced the antimicrobial activity of CPC 250 micrograms/ml.
The reduced activity of CPC in tablet based lozenges resulted from a decreased availability of CPC in solution due to an adsorption of CPC on magnesium stearate. To avoid this reduction in activity tablet based lozenges containing CPC 250 micrograms/ml, or similar concentrations, plus magnesium stearate should contain not more than 0.3% w/w lozenge weight of the lubricant.
本研究旨在确定片剂辅料对氯化十六烷基吡啶（CPC）活性的影响以及辅料与CPC之间的相对相互作用。
开发了一种分析方法来评估CPC与辅料之间的相互作用。通过在不同日期分别让六名志愿者含服每种市售含片后，测定从口咽中可回收的菌落形成单位的减少情况，来研究体内活性。体外测定研究了含片水溶液的相对抗菌活性，以及pH值和片剂辅料对其针对金黄色葡萄球菌、化脓性链球菌和白色念珠菌活性的影响。
体内和体外结果均表明，与先前基于糖果的含片（体内和体外）或相同浓度的CPC水溶液（体外）的结果相比，基于片剂的含片的抗菌活性明显降低。在250微克/毫升的CPC中加入硬脂酸镁悬浮液表明，硬脂酸镁吸附了CPC，且当含量达到含片重量的0.4%及以上时，显著降低了250微克/毫升CPC的抗菌活性。
基于片剂的含片中CPC活性降低是由于CPC吸附在硬脂酸镁上导致溶液中CPC的可用性降低。为避免这种活性降低，含有250微克/毫升CPC或类似浓度且添加硬脂酸镁的基于片剂的含片，其润滑剂含量不应超过含片重量的0.3%（w/w）。
