PEGylation of Nanoemulsion Using Spontaneous Emulsification Method.

Nanoemulsion (NE), a lipid-based drug delivery system, plays an important role in delivering drugs and enhancing bioavailability. They are mainly taken up by the reticuloendothelial system, because of which their bioavailability is diminished, leading to poor therapeutic activity. It is important to protect this delivery system using a coating agent. Thus, we have coated o/w type NE using polyethylene glycol (PEG). The novelty in our study is use of dicarboxylic acid-linked PEG. Furthermore, the spontaneous emulsification method was used in preparation and peg coating, not mentioned previously. After the preparation of NE, various characterization and stability studies were carried out. We have also optimized the ratios for NE and PEG NE by using various concentrations of Smix, PEG, and water. Also, the same has also been plotted in a pseudoternary-phase diagram. As a conclusion, the PEGylation of NE was carried out successfully and may also be used for linking with other ligands because of the presence of COOH group.

Anti-nucleolin Aptamer as a Boom in Rehabilitation of Breast Cancer.

Breast cancer is the second leading cause of cancer-related deaths. It is important to target the complex pathways using a suitable targeted delivery system. Targeted delivery systems can effectively act on cancer cells and lead to the annihilation of tumor proliferation. They mainly employ targeting agents like aptamers linked to the formulation. Based on the expression of the receptors on the surface of the cancer cells, suitable aptamers can be developed. AS1411 is one such aptamer that has the ability to bind to the over-expressed nucleolin present in breast cancer cells. Nucleolin is a phosphoprotein that is involved in various aspects, like cell growth, differentiation and survival. Mostly they are found in the nucleolus, nucleus, cytoplasm and cell surface. The shuttling effect of the nucleolin between the nucleus and cytoplasm serves as a bonus for the AS1411 aptamer. Because of the shutting effect, the internalization of the drug compound or chemotherapeutic drug inside the cell can be achieved. In this article, we have discussed nucleolin, anti-nucleolin aptamer, namely, AS1411, and its application in exhibiting various anticancer activities, including apoptosis, anti-angiogenesis, anti-metastasis, stimulation of tumor suppressor (i.e., P53), and inhibition of tumor inducer. Further, the ways of internalization, namely macropinocytosis, are also discussed. Additionally, we have also discussed the superiority of the aptamer compared to the antibodies as well as the limitations of the aptamers. By considering all the above parameters, we hope this aptamer will be effective in the management and eradication of breast cancer cells.