Role of Nanodiamonds in Drug Delivery and Stem Cell Therapy.

CONTEXT: The use of nanotechnology in medicine and more specifically drug delivery is set to spread rapidly. Currently many substances are under investigation for drug delivery and more specifically for cancer therapy. EVIDENCE ACQUISITION: Nanodiamonds (NDs) have contributed significantly in the development of highly efficient and successful drug delivery systems, and in stem cell therapy. Drug delivery through NDs is an intricate and complex process that deserves special attention to unravel underlying molecular mechanisms in order to overcome certain bottlenecks associated with it. It has already been established that NDs based drug delivery systems have excellent biocompatibility, nontoxicity, photostability and facile surface functionalization properties. RESULTS: There is mounting evidence that suggests that such conjugated delivery systems well retain the properties of nanoparticles like small size, large surface area to volume ratio that provide greater biocatalytic activity to the attached drug in terms of selectivity, loading and stability. CONCLUSIONS: NDs based drug delivery systems may form the basis for the development of effective novel drug delivery vehicles with salient features that may facilitate their utility in fluorescence imaging, target specificity and sustainedrelease.

Immobilization of Aspergillus oryzae ß-Galactosidase on Cellulose Acetate-Polymethylmethacrylate Membrane and Its Application in Hydrolysis of Lactose from Milk and Whey.

The present study demonstrates the immobilization of Aspergillus oryzae ß-galactosidase on cellulose acetate-polymethylmethacrylate (CA-PMMA) membrane and its application in hydrolyzing lactose in dairy industries. The effect of physical and chemical denaturants like pH, temperature, product inhibition by galactose, storage stability, and reuse number of the enzyme immobilized on CA-PMMA membrane has been investigated. Lactose was hydrolyzed from milk and whey in batch reactors at 50°C by free and immobilized ß-galactosidase (IßG). Optimum pH for the free and immobilized enzyme was found to be the same, that is, 4.5. However, IßG retained greater fractions of catalytic activity at lower and higher pH ranges. The temperature optimum for the immobilized enzyme was increased by 10°C. Moreover, Michaelis-Menten constant was increased for IßG as compared to the native one while maximum reaction rate was reduced for the immobilized enzyme. The preserved activity of free and immobilized enzyme was found to be 45% and 83%, respectively, after five weeks of storage at 4°C. Reusability of IßG was observed to be 86% even after fifth repeated use, thereby signifying its application in lactose hydrolysis (as shown in lab-scale batch reactors) in various dairy products including milk and whey.