MTT assay

In order to assess the effect of the corn cob xylan on the cell viability and proliferation rate, xylan solutions at concentrations of 0.1, 0.25, 0.50, 0.75, and 1 mg/ml were placed in contact with human cervical adenocarcinoma cells (HeLa cells) for 24 and 72 h. Finally, the cell viability was determined by the MTT assay. It was observed that regardless of the xylan concentration, the samples tested did not affect the viability of HeLa cells after incubation for 24 h (Figure 13) (Unpublished data). 

Fig. 10. Effect of starch capped copper nanoparticles on cell viability (MTT assay) in case of mouse embryonic fibroblast (3T3L1).

MTX interferes with the growth of cancer cells by inhibiting the metabolism of folic acid. Drug efficacy was evaluated in vitro by MTT assay, as described above, and by Trypan Blue exclusion. Trypan Blue is a non-vital dye excluded by viable cells, but selectively staining dead cells. According to Figure 13.7, higher suppression of cell... 

Fig. 13.7 Effect of MTX-LDH hybrid on cell proliferation (A) and viability (B) as determined by MTT assay and Trypan Blue exclusion, respectively. HOS cells were incubated with free MTX, MTX-LDH hybrid or LDH for 72 h.

Arechabala, B., Coiffard, C., Rivalland, P., Coiffard, L. J. M. and de Roeck-Holtzhauer, Y. (1999). Comparison of cytotoxicity of various surfactants tested on normal human fibroblast cultures using the neutral red test, MTT assay and LDH, J. Appl. Toxicol., 19, 163-165. 

Three C60 derivatives with two to four malonic acid groups (DMA C60, TMA C60, and QMA C60) were prepared and the phototoxicity of these compounds against HeLa cells was determined by MTT assay and cell cycle analysis (Yang et al., 2002). The relative phototoxicity of these compounds was DMA C60 > TMA C60 > QMA C60. Hydroxyl radical quencher mannitol (lOmM) was not able to prevent cells from the damage induced by irradiated DMA C60. DMA C60, together with irradiation, was found to decrease the number of G(l) cells from 63% to 42% and increase G(2) + M cells from 6% to 26%. 

Fig. 4.8 Survival curves of (A) LLC, J774, CT26 cells after 24 h incubation with 2 iM BF4 and (B) J774 cells after 24h incubation with 2 lM BF1—BF6, in both cases followed by a wash and illumination with white light. An MTT assay was carried out after 24 h incubation. Values are means of nine separate wells and bars are SD. Experiments were repeated at least twice...

Reconstructed Human Epidermis in Combination with MTT-Assay... 

A further option to investigate the phototoxic potential of substances is the use of reconstructed human skin models. The evaluation of the cell viability is based on the MTT-assay that is sensitive for the mitochondria activity in cells. Currently, these in vivo substitutes are still under validation and are not approved as full standard test methods for the investigation of the phototoxicity potency of a test chemical. However, several existing models are in use for prevalidation studies and are described elsewhere in more detail [92],... 

Imbert D, Cullander C (1997) Assessment of cornea viability by confocal laser scanning microscopy and MTT assay. Cornea 16 666-674... 

Imbert D, Cullander C (1999) Buccal mucosa in vitro experiments I. Confocal imaging of vital staining and MTT assays for the determination of tissue viability. J Control Release 58 39-50... 

After preincubation in RPMI-1640 medium containing 10% fetal calf semm (PCS), the residual cytotoxic activity of the conjugates against colon 26 tumor cells was measured by MTT assay method at 37°C in vitro. 

Generate a titration curve, by plating cells at different densities and by performing MTT assays at the same time point, e.g., 2 h after plating. The absorbance value for each cell density will allow estimating the number of cells survived/proliferated at the end of your experiment. 

For MTT assays, include a baseline control plate for each condition/treatment. 

Figure 19.7 Experimental procedure forthe assessment of photocytotoxicity (MTT assay) and photo-genotoxicity (comet assay) on reconstructed epidermis. Drugsorformulationscan be applied on the skin surface (topical route) or provided in the culture medium (systemic route see [76]).

The MTT assay was initially developed as a quantitative assay for cell survival and proliferation, not as an in vitro assay for chemosensitivity testing. Further study was required to ascertain if the method accurately predicted the in vivo antitumor activities of anticancer agents. Shimoyama et al. [189] studied the predictability of the MTT assay with respect to a clonogenic assay (Sect. 4.1.1.3.) and showed excellent reproducibility and a close correlation to the in vivo predictability rate of the clonogenic assay. Another study [190] also showed that the MTT assay closely approximated (90%) the clinical activity of anticancer agents. Many authors have since utilized the MTT assay to determine the efficacy of polymeric anticancer drug conjugates. 

All the in vitro cytotoxicity assays were performed using MTT assay... 

Polyfection was carried out with pCMVLuc (a 5 kb pDNA) on HepG2 cells for four hours at 37 °C. After 48 hours, the transfection efficiency was determined from Luciferase activity in cells measured by luminescence (RLU) and the cytotoxicity was evaluated by using the colorimetric MTT assay, dp is the poly lysine degree of polymerization. The transfection efficiency is scored on a 0 to 100 scale where 0 and 1 00 correspond to an absence of transfection and the most effective transfection, respectively compared to the pDNA alone. His is histidyl residue. 

The authors postulated that the enhanced transfection efficiency is due to the higher zeta potential of the higher substituted polyesters, which resulted in an enhanced uptake and increased DNA complexation efficiency. Furthermore, all HBP-DEAPA polymers were tested concerning their cytotoxicity using an MTT assay. All polymers showed such a low cytotoxicity that IC50 values could not be detected at concentrations relevant for transfection. 

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