Simple HPLC determination of benzalkonium chloride in ophthalmic formulations containing antazoline and tetrahydrozoline

A simple and rapid analytical procedure for routine quantification of n-C12H25 and n-C14H29 benzalkonium chloride (C-12 and C-14 BKC) homologs in ophthalmic formulations containing antazoline HCl and tetrahydrozoline HCl by high-performance liquid chromatography was developed and validated. The ophthalmic solution samples can be directly analyzed by reversed-phase on HiQ-Sil C18 column (4.6 mm x 150 mm, i.d., 5-microm particle size) with acetonitrile-sodium acetate buffer (pH 5.0; 0.2 M) (70:30, v/v) as mobile phase. UV Detection was carried out at 262 nm. The method was linear over the selected concentration and ranged from 0.03 to 0.10 mg/ml (r2 = 0.9999) and from 0.01 to 0.05 mg/ml (r2 = 0.9979) for C-12 and C-14 BKC homologs, respectively. The mean percent recoveries were 100.2 and 102.6 and the percent CV values were 1.3 and 3.5 for C-12 and C-14 BKC homologs, respectively. The results demonstrated the good linearity, accuracy, and precision. The method was applied to determine two commercial ophthalmic formulations, and the percent label amounts of total BKC contents were found to be 99.7 and 103.2.     

Reconstruction of contracted eye socket with amniotic membrane graft

PURPOSE: To investigate the use of amniotic membrane graft for socket reconstruction in cases in which forniceal shortening by scar or symblepharon formation has made it difficult to successfully wear an ocular prosthesis. METHODS: A retrospective analysis of 20 contracted eye sockets that underwent forniceal reconstruction with amniotic membrane graft from 1997 to 2001. RESULTS: There were 8 male and 12 female patients, with an age range between 2 and 66 years. Duration of forniceal shortening varied from 2 months to 48 years. The operation was performed in the lower fornix in 13 eyes, upper fornix in 1 eye, and both fornices in 6 eyes. The mean follow-up period was 13.6 months. Eighty percent of cases achieved successful prosthetic fitting after surgery. Four eyes had recurrent forniceal shortening after surgery in which a prosthesis could not be properly fitted. There were no serious complications, such as infection or graft rejection. CONCLUSIONS: The use of amniotic membrane grafts can be a useful option in forniceal reconstruction with a high success rate, a low rate of complications, and without discomfort of donor sites.