Surface-Engineered Cancer Nanomedicine: Rational Design and Recent Progress.

Cancer is highly heterogeneous in nature and characterized by abnormal, uncontrolled cells' growth. It is responsible for the second leading cause of death in the world. Nanotechnology is explored profoundly for sitespecific delivery of cancer chemotherapeutics as well as overcome multidrug-resistance (MDR) challenges in cancer. The progress in the design of various smart biocompatible materials (such as polymers, lipids and inorganic materials) has now revolutionized the area of cancer research for the rational design of nanomedicine by surface engineering with targeting ligands. The small tunable size and surface properties of nanomedicines provide the opportunity of multiple payloads and multivalent-ligand targeting to achieve drug efficacy even in MDR cancer. Furthermore, efforts are being carried out for the development of novel nano-pharmaceutical design, focusing on the delivery of therapeutic and diagnostic agents simultaneously which is called theranostics to assess the progress of therapy in cancer. This review aimed to discuss the physicochemical manipulation of cancer nanomedicine for rational design and recent progress in the area of surface engineering of nanomedicines to improve the efficacy of cancer chemotherapeutics in MDR cancer as well. Moreover, the problem of toxicity of the advanced functional materials that are used in nanomedicines and are exploited to achieve drug targeting in cancer is also addressed.

A two pulse drug delivery system for amoxicillin: an attempt to counter the scourge of bacterial resistance against antibiotics.

Bearing in mind the present scenario of the increasing biological tolerance of bacteria against antibiotics, a time controlled two pulse dosage form of amoxicillin was developed. The compression coating inlay tablet approach was used to deliver the drug in two pulses to different parts of the GIT after a well defined lag time between the two releases. This was made possible by formulating a core containing one of the two drug fractions (intended to be delivered as the second pulse), which was spray coated with a suspension of ethyl cellulose and a hydrophilic but water insoluble agent as a pore former (microcrystalline cellulose). Coating of up to 5% (m/m) was applied over the core tablet, giving a corresponding lag of 3, 5, 7 and 12 h. Increasing the level of coating led to retardation of the water uptake capacity of the core, leading to prolongation of the lag time. Microcrystalline cellulose was used as a hydrophilic but water insoluble porosity modifier in the barrier layer, varying the concentration of which had a significant effect on shortening or prolongation of the lag time. This coated system was further partially compression coated with the remaining drug fraction (to be released as the first immediate release pulse) with a disintegrant, giving a final tablet. The core tablet and the final two pulse inlay tablet were further investigated for their in vitro performance.