Studies of Equilibria Involving the Binary and Ternary Complexes of Aluminium with Eriochrome Cyanine R (ECR) and Cetylpyridinium Chloride (CP)

This paper is concerned with the study of stoichiometry of binary (aluminiumECR) and ternary (aluminium-ECR-CP) complexes of aluminium. Both complexes are shown to be present in the solution and in equilibrium with each other. The formation constant, the reaction rate and the stoichiometry of both complexes have been evaluated and a possible reaction mechanism of the ternary complex formation is proposed in this paper

Some studies using molecular fluorescence and phosphorescence techniques in trace analysis

Imperial Users onl

Optical chemical sensors and biosensors for food safety and security applications

Over the past two decades or so, the incorporation of optical techniques in the development of chemical sensors and biosensors have been investigated resulting in novel and very interesting devices with great promise for many areas of applications. These are truly integrated and interdisciplinary systems that invoke expertise from the fields of chemistry, biochemistry, physics and electronics. Optical chemical sensors and biosensors utilise immobilised reagents and novel materials that can result in a variety of optode designs that are suitable for a variety of measurements in environmental, biomedical, industrial and process control areas

Prob bolehbuang berasaskan gentian optik untuk analisis ion Al (III) di dalam air

Gentian optik telah digunakan di dalam kajilidikan ini sebagai pemandu cahaya daripada sumber cahaya kepada prob. Prob jenis bolehbuang yang dibina dalam kajian ini terdiri daripada reagen Chrome Azurol S (CAS) yang telah dipegunkan di atas penyokong polimer (XAD-2) dan dipegang olehjaring nilon. Penderia ini boleh dijanakan semula menggunakan larutan fluorida, mempunyai had pengesaran 1.0 ´ 10-5 M, kebolehulangan yang tinggi (ralat relatif < 5.0%) dan boleh digunakan untuk penentuan Al(III) dalam air pada julat kepekatan 1.3 ´ 10-5 M - 7.0 ´ 10-4 M. Keputusan analisis yang diperolehi menggunakan penderia ini adalah bolehbanding dengan kaedah yang telah diterima umum seperti spektrofotometri serapan atom mertggunakan relau grafit. EDTA, fosfat, oksalat, tartrat, Cu(II), Fe(III), Be(II) dan Ca(III) didapati menganggu semasa penentuan Al(III) di dalam air

Evaluation of copper(II) Eriochrome cyanine R (ECR) complex immobilized in anion exchange membrane as a potential nitric oxide optical sensor

The immobilization of the copper(ii) complex of Eriochrome cyanine R (Cu(ECR)2) in anion exchange membranes was investigated in the development of an optical sensor for nitric oxide (NO) gas. The change in the absorbance spectrum of Cu(ECR)2 membranes was monitored at 445 nm on exposure to NO gas and a steady-state response was obtained following a 400 s exposure time. This response was highly linear (r2 = 0.996) up to 6 ppm NO and the detection limit was calculated to be 0.848 ppm (∼28.28 µM in solution). This response was 4.7 times more sensitive to changing NO gas concentrations (0–6 ppm) compared with that of Cu(ECR)2 immobilized in silicone rubber films. This response was fully reversible by resubmersion of the membranes in copper(ii) solution following NO exposure and this reversibility was extremely reproducible (0.81%, relative standard deviation, n = 3). These anion exchange membranes were more selective to NO gas rather than O2 (80:1), NO2 (3:1), and CO (7:1) and these gases were shown not to interfere with the reaction of Cu-ECR membranes with NO itself

Molecularly imprinted optical sensing receptor

This chapter is intended to give some insight on the aspects that are related in utilizing molecularly imprinted polymers (MIPs) in optical sensor applications. This includes the synthetic principles, integration techniques, some examples of applications, and also some theoretical understanding on the science behind the working mechanism in using MIPs for optical sensing. The discussions focus mainly on using low power optical sources ranging in the ultra-violet and visible wavelengths and the integration into simple and cost-efective optical components and instrumentations