OBJECTIVE To detect the presence and concentration of methylparaben in cartridges of commercial Brazilian local anesthetics. MATERIAL AND METHODS Twelve commercial brands (4 in glass and 8 in plastic cartridges) of local anesthetic solutions for use in dentistry were purchased from the Brazilian market and analyzed. Different lots of the commercial brands were obtained in different Brazilian ...

Methyl p-hydroxybenzoate (methylparaben) is one of the most important pharmaceutical preservatives. The determination of methylparaben in multi-component pharmaceutical preparations is complicated by the fact that its total concentration seldom exceed 0.1% of the formulation. The possibility that it can interact chemically with active ingredients’ led to a need for a rapid and reliable quantita...

A novel stability-indicating RP-HPLC method was developed for the simultaneous estimation of clindamycin phosphate (hydrophilic), adapalene (hydro-phobic), phenoxyethanol, and methylparaben in topical gel formulations. Optimum chromatographic separation among the analytes and stress-induced degradants peaks was achieved on the XBridge C18 (50 × 4.6 mm, 3.5 µm) column using a mobile phase consis...

A simple and sensitive method was developed for the analysis of preservatives sodium benzoate, methylparaben and propylparaben in nystatin suspensions by reversed-phase high performance liquid chromatography (HPLC), equipped with a C18 column and PDA detector. The mobile phase was a mixture of acetonitrile and acetate buffer of pH 4.4 (35:65 v/v). Under the optimized experimental conditions, se...

The study aims to select suitable ornamental plant species that can survive relatively with high concentrations of acetaminophen and methylparaben in constructed wetlands. Alternanthera spp, Asparagus aethiopicus Chlorophytum comosum are examined withstand three initial concentrations, 20, 100 200 mg/L methylparaben. A total 21 plastic pails each 3 L capacity consisting nine used for pharmaceut...

Simple, rapid, and precise densitometric TLC methods have been established for simultaneous determination of loratadine and preservatives in loratadine–sodium benzoate and loratadine–methylparaben–propylparaben mixtures. Chromatography was performed on aluminium plates precoated with silica gel 60 F254. The mobile phases were n-butyl acetate–carbon tetrachloride–acetic acid–acetonitrile 3:6:0.2...

The application of molecularly imprinted polymers (MIPs) as molecular scavengers for ambient plasma ionization mass spectrometry has been reported for the first time. MIPs were synthesized using methacrylic acid as functional monomer; nicotine, propyphenazone, or methylparaben as templates; ethylene glycol dimethacrylate as a cross-linker; and 2,2'-azobisisobutyronitrile as polymerization initi...

A simultaneous stability-indicating HPLC method for the determination of cisapride, methylparaben and propylparaben in oral suspensions has been developed and validated. Baseline separation was achieved on a C18 column at room temperature (25°C) by gradient elution with mobile phase consisting of solvent A: 10% v/v acetonitrile in 0.13% w/v sodium-1pentanesulfonate pH 8 and solvent B: acetonitr...