ABSTRACT
In this study, a rapid method for the detection of berberine hydrochloride (BRH) was developed based on a water-soluble pyrenyl probe, 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS). This method features low cost, good selectivity, high sensitivity and a fast response. The sensing mechanism of this probe is attributed to the formation of a complex between HPTS and BRH induced by electrostatic interaction and π-π stacking. To the best of our knowledge, this is the first fluorescent sensor for BRH based on organic materials that has low cost and a visual response. The detection limit of this method was as low as 1.24 µM and the linear response range is 2-50 µM. This method also allowed rapid detection of BRH real samples.
Subject(s)
Berberine/chemistry , Drugs, Chinese Herbal/analysis , Fluorophotometry/methods , Pyrenes/chemistry , Berberine/urine , Humans , Limit of Detection , SolubilityABSTRACT
PURPOSE: To review the use of ophthalmic rose bengal to assess the ocular surface, especially considering the grading scales used. METHODS: A literature search was undertaken to identify reports where either rose bengal or lissamine green had been used as a 'vital' stain, with a special interest in identifying studies that provided data before and after treatment for dry eye and also considered the mechanism of action of these two chemicals. RESULTS: Between 1985 and 2006, numerous clinical studies used a consistent grading scheme (that attributed to Van Bijsterveld) to assess the outcome of artificial tear treatments on dry eye patients. With such consistency, including the adoption of a treatment period of 1 month, comparisons can be made to indicate the efficacy of rose bengal staining to assess reduction in ocular surface desiccation. However, in the following years, several alternative grading schemes have been used for both rose bengal and lissamine green and assessment periods have been variable so making inter-study comparisons considerably more difficult to undertake. An attribute of rose bengal appears to be its ability to stain the nuclei of cells, but whether this also occurs for lissamine green is unclear. CONCLUSIONS: Ophthalmic rose bengal has been successfully adopted for use to assess the ocular surface over many years as a vital stain. More research is needed to assess whether lissamine green ocular surface staining can simply be substituted for rose bengal in evaluation of dry eye treatments.
Subject(s)
Cornea/pathology , Dry Eye Syndromes/drug therapy , Dry Eye Syndromes/pathology , Fluorophotometry/methods , Ophthalmic Solutions/therapeutic use , Patient Outcome Assessment , Rose Bengal , Cornea/drug effects , Fluorescent Dyes , Humans , Ophthalmoscopy/methods , Staining and Labeling/methods , Treatment OutcomeABSTRACT
To date, little information has been available about the actual amount of tear secretion in dry eyes. In the present study tear secretion was studied in 20 consecutive dry eye patients [40 eyes; Schirmer test after topical anesthesia < 5.5 mm/5 min; at least moderate squamous metaplasia of the conjunctival epithelium; bengal rose staining (Bijsterveld score > 4); severe dry eye complaints]. Tear secretion was evaluated by automated, computerized objective fluorophotometry and compared with that in an age-matched healthy control group. Tear secretion of the dry eyes examined was found to have decreased drastically (0.2 +/- 0.2 microliters/min) compared with that in healthy control eyes (1.2 +/- 0.5 microliters/min; P < 0.001). None of the dry eyes had a tear secretion of > 0.4 microliters/min.