Validated Chromatographic Methods for the Simultaneous Determination of Sulfacetamide Sodium and Prednisolone Acetate in their Ophthalmic Suspension.

Two specific, sensitive, rapid and accurate chromatographic methods have been developed, optimized and validated for the simultaneous determination of sulfacetamide sodium and prednisolone acetate in pure forms and in their binary mixture. The first method is an isocratic Reversed phase-high performance liquid chromatography method where a rapid separation was achieved on a Zorbax ODS column using a green mobile phase of methanol: water (80:20, v/v) and pH adjusted to 5.0 ± 0.2 with orthophosphoric acid. The retention times (tR) were 2.21 and 3.64 min for sulfacetamide sodium and prednisolone acetate, respectively. The separated peaks were detected at 254 nm. The second method is a thin layer chromatography-densitometric method where the two drugs were separated on silica gel plates using a simple mobile phase of chloroform: methanol (90:10, v/v) and scanning of the separated bands was at 254 nm. The retardation factors (Rf) values were 0.37 and 0.64 for sulfacetamide sodium and prednisolone acetate, respectively. The suggested methods were validated in compliance with the ICH guidelines and were successfully applied to determine both drugs in their pure forms, laboratory prepared mixtures and dosage form. The obtained results were statistically compared to the official method where no significant difference was obtained with respect to both accuracy and precision.

Transport of sulfacetamide and levofloxacin in granular porous media under various conditions: Experimental observations and model simulations.

Understanding the fate and transport of antibiotics in porous media can help reduce their contamination risks to soil and groundwater systems. In this work, batch and column experiments were conducted to determine the interactions between two representative antibiotics, sulfacetamide (SA) and levofloxacin (LEV), and sand porous media under various solution pH, humic acid (HA) concentration, grain size, and moisture content conditions. Batch sorption experimental results indicated that the sand had relatively strong bonding affinity to LEV, but little sorption of SA under different pH, HA concentration, grain size conditions. Results from the packed sand column experiments showed that SA had extremely high mobility in the porous media for all combinations of pH, HA concentration, grain size, and moisture content. The mass recovery of SA was higher than 98.5% in all the columns with the exception of the one packed with fine sand (97.2%). The retention of LEV in the columns was much higher and the recovery rates ranged from 0% to 71.1%. Decreases in solution pH, HA concentration, grain size, or moisture content reduced the mobility of LEV in the columns under the tested conditions. These results indicated that type of antibiotics and environmental conditions also played an important role in controlling their fate and transport in porous media. Mathematical models were applied to simulate and interpret experimental data, and model simulations described the interactions between the two antibiotics and sand porous media very well. Findings from this study elucidated the key factors and processes controlling the fate of SA and LEV in porous media, which can inform the prediction and assessment of the environmental risks of antibiotics.

Carbon nanotube embedded poly 1,5-diaminonapthalene modified pyrolytic graphite sensor for the determination of sulfacetamide in pharmaceutical formulations.

An electrochemically conductive single-walled carbon nanotube (SWCNT) embedded poly 1,5-diaminonapthalene (DAN) modified sensor has been developed for the determination of sulfacetamide (SFA). The surface morphology of the modified sensor has been characterized by FE-SEM, which revealed good dispersion of the carbon nanotube in polymer matrix. SFA was quantified using square wave voltammetry in phosphate buffer of pH 7.2, which acted as supporting electrolyte during analysis. The modified sensor exhibited an effective catalytic response towards the oxidation of SFA with excellent reproducibility and stability. The peak current of SFA was found to be linear in the concentration range of 0.005-1.5 mM and detection limit and sensitivity of 0.11 µM (S/N=3) and 23.977 µA mM(-1), respectively were observed. The analytical utility of method was checked by determining the SFA in various pharmacological dosage forms. The results obtained from the voltammetry were validated by comparing the results with those obtained from HPLC. The proposed method is sensitive, simple, rapid and reliable and is useful for the routine analysis of SFA in pharmaceutical laboratories.

Optimal conditions for determination of zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feed by micellar electrokinetic capillary chromatography.

A separation technique for zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide in animal feedstuffs by micellar electrokinetic capillary chromatography (MEKC) was developed. The running buffer was 20 mmol l(-1) borate, 20 mmol l(-1) phosphate, pH 8.4, containing 20 mmol l(-1) sodium dodecylsulphate and 10% (v/v) methanol. MEKC was performed at 25 degrees C; the applied voltage was 25 kV with a running pressure of 10 mbar. Simultaneous UV detection for all analytes was at 215 nm. The method was validated for specificity, accuracy, linearity, precision and robustness. It was shown to be specific, accurate (recoveries were 99.7 +/- 0.3, 99.9 +/- 0.9, 99.8 +/- 1.0 and 99.5 +/- 0.4, respectively, for oxytetracycline-, sulfacetamide-, polymyxin B- and zinc bacitracin-spiked samples of feed for cow, pigs, chicken and cattle), linear over the tested range (correlation coefficients > or =0.9987) and precise (RSDs below 1.8% for each analyte). The method was applied to determine zinc bacitracin, polymyxin B, oxytetracycline and sulfacetamide as additives in animal feed.

[Determination of 12 sulfonamides in cosmetics by ultra performance liquid chromatography].

A method for the determination of 12 sulfonamides (SAs) (sulfanilamide, sulfamonomethoxine, sulfacetamide, sulfamethoxazole, sulfadiazine, sulfisoxazole, sulfathiazole, sulfadi-methoxine, sulfamerazine, sulfaquinoxaline, sulfamethazine, sulfanitran) in cosmetics was developed by ultra performance liquid chromatography with photodiode array detector (UPLC-PDA). The chromatographic column used was Acquity UPLC BEHC C18 (50 mm x 2. 1 mm, 1. 7 microm) and the mobile phase was acetonitrile-0. 1% formic acid aqueous solution. A gradient elution program was utilized for the separation and determination. After liquid-liquid extraction, SAs were separated and detected by UPLC-PDA. The qualification analysis was done by using retention time and spectrum, and the quantification was based on the detection wavelength of 268 nm. The limits of qualification (S/N = 3) and quantification (S/N = 10) for 12 SAs were 1 microg/g and 2 -3 microg/g, respectively. The correlation coefficient of linear calibration curve was over 0. 999 7 within the SAs concentration range of 1 - 25 mg/L (except sulfanitran 0. 5 - 12. 5 mg/L). At the spiked levels of 40 and 8 microg (except sulfanitran 20 and 4 microg), the average recoveries for 12 SAs were 86. 8% - 98. 1% and 80. 1% - 96. 9%, respectively. Relative standard deviations were less than 10%. Routine tests show that the method is simple, fast, and has a good separation efficiency. It can be routinely used for the determination of these SAs in cosmetics.

Determination of prednisolone acetate, sulfacetamide and phenylefrine in local pharmaceutical preparations by micellar electrokinetic chromatography.

A new, rapid and simple method is described and applied to resolve and quantify mixtures of prednisolone acetate, sulfacetamide and phenylefrine. The determination was accomplished by micellar electrokinetic capillary chromatography (MEKC) using a fused silica capillary (57 cm x 75 microm ID). The separation was carried out at 25 degrees C and 30 kV, using a 5 mM phosphate-5 mM borate buffer adjusted to pH 8.2, 40 mM sodium dodecylsulfate (SDS) as background electrolyte. Under these conditions, the run time was 6.5 min and the limits of quantification were about 0.5 mg l(-1) for every component. Repeatability and reproducibility studies achieved were showing no significant differences at 95% confidence level. Then, multivariate calibration regression spectrophotometric methods (PLS-1, PLS-2 and PCR) were applied providing, especially PLS-1, a clear example of the high resolving power of these techniques. The MEKC method has been applied for quantifying these compounds in different commercial pharmaceuticals products and the method gave good results when it is compared with the spectrophotometric method. The pharmaceutical preparations do not require any separation step by the two described procedures.

Spectrophotometric determination of sulphacetamide.

A new rapid selective spectrophotometric method for the determination of sulphacetamide is described. The drug forms a orange-yellow colored complex with Cerium(IV) in sulfuric acid media which is extracted into ethyl acetate. The complex exhibits a maximum absorbance at 440 nm with a molar absorptivity of 3 x 10(2) 1 mol-1 cm-1. The system obeys Beer's law in the concentration range of 0.07-1.1 mg of sulphacetamide. The various parameters for the optimum extraction conditions are discussed. The method is applied to the determination of sulphacetamide in dosage forms.

[Determination of sulfacetamide sodium and sulfanilamide in shao tang ling ointment by high performance liquid chromatography].

An HPLC method for the determination of sulfacetamide sodium and sulfanilamide in Shao Tang Ling ointment was developed. The chromatographic conditions were: column, Spherisorb C18, mobile phase, methanol-0.25% (V/V)-acetic acid solution (7:93); detector UV-257 nm. The average recoveries were 98.9% (n = 5), RSD = 0.64% for sulfacetamide sodium and 99.3% (n = 5), RSD = 1.58% for sulfanilamide. The analytical method is simple, quick, accurate and reproducible.

Spectrofluorimetric determination of sulphonamides in pharmaceutical compounds and foods.

Spectrofluorimetry and room temperature photochemically-induced fluorescence (RTPF) have been applied to the determination of sulphacetamide (SAC), sulphaguanidine (SG) and sulphamethazine (SMT) in milk and pharmaceutical formulations. The methods are suitable for determining 0.02-0.10 micrograms ml of SAC, 0.10-0.50 micrograms ml of SG, and 0.40-1.00 micrograms of SMT.

Determination of sulphacetamide, sulphadimidine or sulphathiourea in the presence of their degradation products using first derivative spectrophotometry.

A method is presented for the determination of sulphacetamide sodium, sulphadimidine and sulphathiourea in the presence of their acid-induced degradation products using first derivative spectrophotometry. By measuring the absolute value of the first derivative curves at the zero contribution of the corresponding degradation products, the concentration of the intact drug can be calculated directly without interference of the degradation product. The validity of the method was confirmed using synthetic mixtures of the intact drugs with their degradation products.

Effects of preservatives, steroids, and ethylenediaminetetraacetate on the antimicrobial activity of sulfacetamide.

The effect of EDTA (ethylenediaminetetraacetate), steroids, and preservatives on the antimicrobial activity of 10% sodium sulfacetamide solutions was evaluated in this study by kill rate and minimum inhibitory concentration (MIC) using five representative microorganisms. The results indicate that thimerosal-preserved sulfacetamide solutions containing EDTA are more effective against Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus epidermidis, and Candida albicans than similar paraben-preserved solutions. Furthermore, the addition of EDTA improves the kill rate, but not the MIC, for the Pseudomonas, Serratia, and Candida species regardless of the preservative. The combination of a steroid with sulfacetamide does not affect its antimicrobial activity.

Degradation studies on sulphacetamide eye-drops. Part 2: Spectrophotometric evaluation of decomposition products of UV-irradiated solutions of sulphacetamide.

Multicomponent spectrophotometric assay methods have been used for quantitative determination of major photodecomposition products of sulphacetamide solutions. The reproducibility of the assay method lie within 4% of error. The hydrolysis of sulphacetamide to sulphanilamide and the oxidation of sulphanilamide to a blue product is a first-order reaction while the formation of azo dye from sulphanilamide is found to be a second-order reaction. A general scheme of photodegration pathways for sulphacetamide and sulphanilamide is presented.

Spectrophotometric determination of chloramphenicol-sulphacetamide in eye drops.

A rapid method for the determination of chloramphenicol in chloramphenicol-sulphacetamide drops is discussed. The method depends upon precipitating sulphacetamide as its silver salt by a solution of silver nitrate. Chloramphenicol is determined in the filtrate using the modified Vierordt's method. Sulphacetamide was determined by suitably diluting the drops with 0.01 N H2SO4 and then applying the modified Vierordt's method. The presence of macrogols proved not to interfere with the determination. Mean percentage recoveries +/- s.d. for chloramphenicol and sulphacetamide were found to be 100.8 +/- 0.95 and 100.2 +/- 1.0, respectively.

Facile separation of sulfonamides from their degradates by liquid--liquid extraction.

Regulation of acidity for protonation of the free N4-amine can provide for the selective liquid--liquid extraction isolation of a sulfonamide from its degradation products. This principle is applied for the stability-indicating determination of sulfacetamide in the presence of sulfanilamide, sulfaquinoxaline in feed, and sulfabromomethazine in dosage forms. In solution, sulfabromomethazine can exhibit photodecomposition to sulfamethazine. The mean relative errors of the these methods and the precision, represented by relative standard deviations, are each typically less than 2%.

[Effect of tranquilizers and analgesics on the permeability of the histohematic barriers for sulfacyl in inflammation]. / Vliianie trankvilizatorov i anal'getikov na pronitsaemost' gisto-gematicheskikh bar'erov dlia sul'fatsila v usloviiakh vospaleniia

The effect of neurotropics (analgetics and tranquilizers) on the permeability of histo-blood barriers in normalcy and pathology was wound to be dissimilar. In tests conducted on intact rats the studied neurotropic agents used in pharmacological doses did not affect the permeability of the histological-blood barriers of the brain and spleen with respect to the indicator--sodium sulfacyl. In rats with an inflammation focus the same drugs produced changes of the said factor, not always similar in their orientation (rise of fall).