Labeling efficiency time effects

Also discussed in Chapter 1 is the issue of reading ability and reading levels in terms of the usefulness of the label. The chapter also presents data associated with the evaluation of label effectiveness and discusses three major criteria against which to evaluate results, including time, optical efficiency, and the communication value of labels, and relates these to the issues associated with hazard labeling. The reader is provided with a discussion of the methods now available and in use for testing the efficiency and effectiveness of labeling. 

To remove the labels still attached to the chips, a cost-effective and efficient means of removing a waterproof adhesive had to be devised. After finally finding a detergent wash that would work, he explains, it had to be optimized with respect to temperature, washing time, concentration of detergent, power of mixing, and, of course, concentration of chips. 

With the optimized lipid composition (opDC ePC DOPE eSph Choi DC-Chol = 5 5 5 12 3), the HVJ-cationic liposomes showed 100 to 800 times greater transfection efficiency in vitro compared with the conventional HVJ-PS liposomes. The presence of serum (10% FCS) in the transfection mixture did not decrease luciferase activity significantly. Even 70% FCS reduced the activity by less than 40%. LacZ gene expression showed that transfection efficiency of BHK-21 cells by optimized HVJ-cationic liposomes (opDC) and by conventional HVJ-cationic liposomes (DC) was 90-100% and 50-60%, respectively. With conventional HVJ-anionic liposomes (PS), LacZ expression was found in only 1-3% of the cells. The optimized HVJ-cationic liposomes were also much more effective for the transfer of FITC-labeled ODNs to cultured cells [16]. 

While these techniques are sensitive, they can be hampered by cytotoxic side effects of the labeling procedures and can be limited by dilution and loss of the marker over time as a result of cell division [55], Thus, while useful for measuring the efficiency of acute delivery, these techniques may offer minimal long-term information regarding cell survival, proliferation, and differentiation [56],... 

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