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Polymorphs have a tendency to undergo solution-mediated transformation from one form to another during crystallization. Various in situ techniques explored for understanding the crystallization process include, Raman spectroscopy, near-infrared spectroscopy (NIR), and focused beam reflectance measurement (FBRM). Both Raman and NIR techniques are used for polymorphic identification. FBRM has gained much popularity as an ideal technique for studying and improving particle size. The crystallization process can be improved using FBRM by studying the meta-stable zone, temperature of crystallization, and primary and secondary nucleation. This FBRM technique offers a quick and time-saving approach along with insight on the particle size of the product. The same technique can be used during scale up to understand and monitor crystallization processes. This report describes a different application of FBRM, which involves monitoring the changes in chord length distribution as a result of polymorphic transformation associated with temperature during crystallization. Needle-shaped Form III of acitretin undergoes solvent-mediated transformation to cube-shaped Form II. This polymorphic transformation is monitored by monitoring the chord length distribution.

Polymorphism is a solid-state phenomenon; hence, solid-state techniques such as XRPD, DSC, and FT-IR are used for characterization. Many a time, only XRPD is used. These techniques ignore the most important aspects, i.e., chemical purity and the chemical integrity of the polymorph, which can be confirmed by techniques such as 1 H NMR, HPLC, and elemental analysis. The aim of this article is to emphasize how techniques such as 1 H NMR, elemental analysis, and HPLC purity in addition to other solid-state characterization techniques would help to prove that the drug really exists in different polymorphic forms. H 1 NMR, HPLC, and elemental analysis reveal the formation of different compounds and not polymorphs in the case of pioglitazone•HCl and glyburide. In the cases of irbesartan and ropinirole•HCl use of a single solid-state characterization technique such as XRPD is not enough for establishing the existence of different polymorphic forms.

Nanotechnology is a multidisciplinary branch of science that deals with the production of materials that are of size range of 1-100nm. The unique physical and chemical properties of nanoparticles have enabled their applications in various fields including optical sensor, imaging, medicine and diagnostics etc. Among all nanoparticles, silver nanoparticles have found wide applications. There are various methods available for biosynthesis of Silver nanoparticles including physical and chemical methods. But these methods are expensive and are hazardous. The present study focuses on developing an eco-friendly and economical method for synthesis of nanoparticles using Aspergillus flavus. Cell free extract of Aspergillus flavus was treated with Silver nitrate (AgNO3). The production of nanoparticles was monitored using UV Visible Spectrophotometer. The biosynthesized nanoparticles were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Energy-dispersive X-Ray spectroscopy (EDX). The biosynthesis was optimized for different parameters such as pH, temperature and AgNO3 concentration.

Nanotechnology is a field of science that involves the production of particles with at least one dimension less than 100 nm. These nanoparticles have found various applications in the field of biomedicine, diagnostic, antimicrobial and anticancer agents etc. The present investigation focuses on the development of economical and eco-friendly methods for the biosynthesis of Silver Nanoparticles using cell free extract of Penicillium sps. The production of nanoparticles was monitored by scanning through UV Visible Spectrophotometer in the range of 300-70 nm. Size and shape of nanoparticles were determined by Scanning Electron Microscope (SEM) while the elemental composition was studied by Energy- dispersive X-ray spectroscopy (EDX). The presence of various functional groups that might have contributed for stability of silver nanoparticles was determined by Fourier transform infrared spectroscopy (FTIR). Antioxidant activities of silver nanoparticles were studied by 2,2- diphenylpicrylhydrazyl (DPPH) scavenging, Hydrogen peroxide (H2 O2 ) radical scavenging and Reducing Power Assay (RPA). The nanoparticles showed dose dependent increase in antioxidant activities with IC50 value of 314.47 + 4.96 µg/ml and 317.34 + 4.40 µg/ml respectively for DPPH scavenging and H2 O2 radical scavenging activity