Self-assembly of betulinic acid, a renewable nano-sized 6-6-6-6-5 pentacyclic triterpenic acid studied in twenty two organic liquids and alcohol-water mixtures showed that it self-assembled in all the liquids studied affording strong gels in nineteen organic liquids and also in alcohol-water mixtures. Optical and electron microscopy and atomic force microscopy studies revealed fibrillar networks having fibers of nano- to micro-metre cross sections and micrometre lengths.

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Betulin, a naturally occurring 6-6-6-6-5 pentacyclic dihydroxy-triterpenoid, is extractable from the bark of white birch (Betula papyrifera). We report the first self-assembly properties of betulin in different liquids. The molecule spontaneously self-assembled in different media, yielding flower-like architectures of nano- to micrometers diameters via the formation of fibrillar networks. The self-assemblies have been characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, FTIR, and X-ray diffraction studies. The porous microstructure of the self-assemblies has been utilized for the entrapment of fluorophore such as rhodamine-B and the anticancer drug doxorubicin. Moreover, the removal of toxic dyes such as rhodamine 6G, crystal violet, methylene blue, and cresol red has also been demonstrated.

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Punica granatum juice, a delicious multivitamin drink of great medicinal significance, is rich in different types of phytochemicals, such as terpenoids, alkaloids, sterols, polyphenols, sugars, fatty acids, aromatic compounds, amino acids, tocopherols, etc. We have demonstrated the use of the juice for the synthesis of gold nanoparticles (AuNPs) at room temperature under very mild conditions. The synthesis of the AuNPs was complete in few minutes and no extra stabilizing or capping agents were necessary. The size of the nanoparticles could be controlled by varying the concentration of the fruit extract. The AuNPs were characterized by surface plasmon resonance spectroscopy, high resolution transmission electron microscopy, fourier transform infrared spectroscopy and X-ray diffraction studies. Catalytic activity of the synthesized colloidal AuNPs has also been demonstrated.

The study was aimed to develop folate receptor mediated delivery of self assembled betulinic acid nano fibers to leukemic cells and to investigate their mode of action.

The bark extract of the traditional ayurvedic medicinal plant Saraca indica containing redox active polyphenolic compounds has been utilized for the one-step synthesis of gold nanoparticles at room temperature. The polyphenolic compounds acted as the reducing agent as well as the stabilizing agent without any additional capping agent. The synthesis of the gold nanoparticles of 15-23 nm size was complete in several minutes and no photo irradiation or heat treatment was necessary. Surface plasmon resonance, HRTEM, AFM, X-ray diffraction, and FTIR studies have been carried out to characterize the nanoparticles. Gold nanoparticles synthesized were of triangular, tetragonal, pentagonal, hexagonal, and spherical shapes. The synthesized gold nanoparticles have been used as a catalyst for the reduction of 4-nitrophenol to 4-aminophenol at room temperature and the kinetics of the reduction reaction has been studied spectrophotometrically.