Search

Due to its high analytical sensitivity and field deplorability, surface enhanced Raman spectroscopy (SERS) has emerged as an analytical tool for detecting environmental toxicants in different matrices. Progress has been made towards development of methods for depositing nanostructures onto solid platforms to design SERS substrates. The properties of the solid platforms used for SERS substrates fabrications such as electrical and heat conductivity, malleability and foldability, have significant influence on then design of the nanostructures and are critical for SERS technique. This review takes a look at recent advances in commonly employed conductive solid materials such as indium tin oxide, carbon fiber, silicon wafers, polyaniline fiber and carbon nanotubes as the supporting platforms for fabricating SERS substrates. It also examines their influence on the fabrication method, the morphology of the nanostructures formed as well as the hot spot density on the resultant novel SERS substrates. Real world applications of these substrates for the detection of environmental toxicants over the past decade have been shown. The review indicates that while significant advances have been made on the use of the conductive properties of these support platforms for SERS substrate fabrication, their subsequent application to detect environmental toxicants have not been fully explored.

Two new spectrophotometric procedures for determining trace amounts of bromazepam and clonazepam, 1,4-benzodiazepine derivatives in their pure and pharmaceutical dosage forms have been developed. The methods are based on forming C.T. complexes with chloranil in chloroform or ethanol at alkaline pH. The absorbance of the formed C.T. complexes were measured at λ = 330 nm and λ = 375 nm for bromazepam and clonazepam, respectively. Linear calibration curves were obtained in the ranges of 31.6–316.0 µg mL−1 for bromazepam and of 63.2–316.0 µg mL−1 for clonazepam. Average recoveries of 99.00–99.60% and 98.57–99.60% were obtained. These reflect 0.5–1.11% and 0.67–1.74% relative errors for bromazepam and clonazepam, respectively. The methods showed standard deviations of 0.6–2.00 and 0.75–1.11 with variance coefficients of 0.63–1.58% and 0.32–1.19% for bromazepam and clonazepam tablets, respectively. Student t-test and F-test statistical treatments were applied for the results obtained by the two methods...