Optical whole-cell biosensor using Chlorella vulgaris designed for monitoring herbicides

Abstract

. Optical whole-cell biosensor using Chlorella vulgaris designed for monitoring herbicides. Biosensors and Bioelectronics, Elsevier, 2003, 18 (4), pp.547-463. <10.1016/S0956-5663(02)00157-4>. <emse-00520269> & Bioelectronics, 2003& Bioelectronics, , 18(4), 457-63, doi:10.1016 Biosensors AbstractAn optical biosensor was designed for determination of herbicides as aquatic contaminants. Detection was obtained with immobilised Chlorella vulgaris microalgae entrapped on a quartz microfibre filter and placed in a five-membrane-home-made-flow cell. The algal chlorophyll fluorescence modified by the presence of herbicides was collected at the tip of an optical fibre bundle and sent to a fluorimeter. A continuous culture was set up to produce algal cells in reproducible conditions for measurement optimisation. Effects of flow rate, algal density, temperature, and pH on the biosensor response to atrazine were studied. Reversibility and detection limits were determined for DNOC and atrazine, simazine, isoproturon, diuron. Detection of photosystem II (PSII) herbicides was achieved at sub-ppb concentration level. K Ke ey yw wo or rd ds s: :

Rapid Detection of Heavy Metals with the Response of Carotenoids in Daucus Carota

“…Although the cell showed good sensitivity and reproducibility in the tests with a few types of heavy metals, further work is required to incorporate the cell into a biosensor. The factors which influence the response of cell, such as the condition of the culture, the number of cell to be used in detection, the detection condition such as pH are yet to be studied [2], [3], [32]. The cells cultured respond differently in different growth stage, while different number of cells used affects the signal produced as well.…”

“…pH is most widely studied factor, as bioconponents are affected by the pH of the environment [32], [36].…”

Response of Chlorella vulgaris as Whole cell Bioindicator for Atrazine and 2 4 Dichlorophenoxyacetic Acid Detection

“…Studies by Pazmiño et al [14] have suggested that synthesis of auxin could be disrupted due to higher concentration of 2,4-D, whereas carbon assimilation and photochemical reaction might be strengthened through low concentration of 2,4-D. Previous research done by Védrine et al [15] on wholecell biosensor using C. vulgaris for monitoring herbicides showed that the algae could response affectively in the presence of atrazine. In this study, an optimal pH of 7 was maintained in room temperature.…”

Highly Specific Biosensors to Herbicides, Based on Sensitive- and Resistant-Mutants of Microalgae

“…For example, an optical fiber based biosensor was developed for atrazine and endrine monitoring in water using Scenedesmus subspicatus cells, immobilized on filter paper and covered with a thin alginate layer hardened with calcium chloride (Frense et al, 1998). Chlorella vulgaris was immobilized at the tip of an optical fiber bundle placed inside a homemade microcell (Naessens et al, 2000), or in a rotating support holding up to five different membranes to increase the number of assays (Védrine et al, 2003), and used for the detection of herbicides affecting photosystem II (PSII) such as triazines (atrazine, simazine) or phenylureas (diuron, isoproturon) herbicides at sub-µgL -1 concentration level. NguyenNgoc et al (2007) investigated the response of a microalgal biosensor to the herbicide Diuron® by measuring the variation of the chlorophyll fluorescence of Chlorella vulgaris strain conveniently entrapped into a sol-gel translucent support.…”