The treatment of central nervous system (CNS) disorders always remains a challenge for the researchers. The presence of various physiological barriers, primarily the blood–brain barrier (BBB) limits the accessibility of the brain and hinders the efficacy of various drug therapies. Hence, drug targeting to the brain, particularly to the diseased cells by circumventing the physiological barriers is essential to develop a promising therapy for the treatment of brain disorders. Presently, the investigations emphasize the role of different nanocarrier systems or surface modified target specific novel carrier system to improve the efficiency and reduce the side effects of the brain therapeutics. Such approaches supposed to circumvent the BBB or have the ability to cross the barrier function and thus increases the drug concentration in the brain. Although the efficacy of novel carrier system depends upon various physiological factors like active efflux transport, protein corona of the brain, stability, and toxicity of the nanocarrier, physicochemical properties, patient-related factors and many more. Hence, to develop a promising carrier system, it is essential to understand the physiology of the brain and BBB and also the other associated factors. Along with this, some alternative route like direct nose-to-brain drug delivery can also offer a better means to access the brain without exposure of the BBB. In this review, we have discussed the role of various physiological barriers including the BBB and blood-cerebrospinal fluid barrier (BCSFB) on the drug therapy and the mechanism of drug transport across the BBB. Further, we discussed different novel strategies for brain targeting of drug including, polymeric nanoparticles, lipidic nanoparticles, inorganic nanoparticles, liposomes, nanogels, nanoemulsions, dendrimers, quantum dots, etc. along with the intranasal drug delivery to the brain. We have also illustrated various factors affecting the drug targeting efficiency of the developed novel carrier system.

A scalable manufacturing process for fabricating active-matrix backplanes on low-cost flexible substrates, a key enabler for electronic-paper displays, is presented. This process is based on solution processing, ink-jet printing, and laser patterning. A multilayer architecture is employed to enable high aperture ratio and array performance. These backplanes were combined with E Ink electrophoretic media to create high-performance displays that have high contrast, are bistable, and can be flexed repeatedly to a radius of curvature of 5 mm

We have developed a scalable manufacturing process for active matrix displays compatible with low temperature plastic substrates and have applied this technology to the fabrication of flexible SVGA display backplanes. We combined these backplanes with E Ink® Imaging Film to produce 100 PPI SVGA (800×600 pixel) displays exhibiting grey scale and with a high aperture ratio. Power consumption is zero in between image changes. Flexible high information content e‐paper displays will change the way in which information is conveyed by enabling lightweight, robust e‐reader devices.

The review article explores the various problems associated with hydrolysis which occurs during formulation and the various solutions of it. The moisture content either the drug or the excipients affect the formulation, by hydrolysis, thus it is important to find out ways to prevent it and thus protect the formulation and provide a greater stability under processing and storage condition. The common moisture interactions which occur are water-solid interactions, water-amorphous solid interactions, drug-excipient interactions and the change in the crystal habit of the solids. The science behind the hydrolysis is due to the moisture sensitive functional group of the ingredient, and the other freely moveable living groups. Amides, lactams, esters, lactones, chloride are the functional groups most susceptible to hydrolysis. The hydrolysis of excipients, including both polymeric and non-polymeric also show great impact on the stability of the drugs. The excipients used in the form of sweeteners, plasticizers, solvents, surfactants, wetting agents, emollients, antioxidants, lubricants, preservatives, and etc. have effects on the drug stability. As a result, several solutions are found to prevent unwanted hydrolysis in different dosage forms. The main parameters which are likely to solve this issue are pH, buffers, surfactants, non-aqueous solutions, suspensions, lyophilization, packaging and an adequate proportion of the desiccant use.

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