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Publications (6)2.33 Total impact

  • S Rajalakshmi, A P Pawar, A J Mali, C Bothiraja
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    ABSTRACT: Plumbagin, a bioactive natural lipophilic molecule, has wide pharmacological actions. It shows solubility limited low oral bioavailability. The aim of this study was to improve biopharmaceutical properties of plumbagin using crystal engineering techniques. Plumbagin crystals were prepared using anti-solvent precipitation (PPL), melt solidification (MPL), melt quenching (MQPL), sonocrystallization (SPL) and melt sonocrystallization (MSPL) processes and compared with properties of reference plumbagin. No significant changes in solubility and dissolution rate were observed for sintered MPL and MQPL crystals, whereas slightly higher Q 30min (cumulative percentage release in 30 min) and lower t 50% (time required for 50% w/w drug release) was observed for irregular shaped PPL crystals due to a two-fold decrease in the crystal size. As compared to needle shaped reference plumbagin crystals, the spongy and thread shaped crystals of SPL and MSPL showed two- and three-fold increase in solubility, seven- and eight-fold increase in Q 30min due to five- and ten-fold reduction in crystal size with increased surface area and reduced diffusion pathway of SPL and MSPL, respectively. Higher sonication amplitude, time, concentration and lower processing temperature favored formation of smaller crystals due to instantaneous supersaturation and nucleation. DSC and FT-IR spectra did not show significant difference. Low-intensity peaks in x-ray diffraction and improved flow properties were noticed for SPL and MSPL. Moreover, an in vivo study in Wistar rats also justified improvement in the therapeutic efficacy of SPL and MSPL. The study demonstrated the utility of sonoprocess to improve pharmaceutical properties of bioactive plumbagin.
    Materials Research Express. 05/2014; 1(2):025405.
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    ABSTRACT: Andrographolide, a natural lipophilic molecule, has a wide range of pharmacological actions. However, due to low aqueous solubility, it has low oral bioavailability. The purpose of the study was to increase the solubility and dissolution rate of isolated andrographolide by formulating its solid dispersion. Solid dispersions were obtained by a spray-drying technique using different ratios of drug to polyvinylpyrrolidine (PVP K-30). Solid dispersions in compression with isolated drug and corresponding physical mixtures were characterized for various molecular pharmaceutical properties and subjected to stability study for up to 3 months. A five-fold increase in saturation solubility of andrographolide with higher values of Q(5 min) (cumulative percentage release in 5 min) and lower values of t(75%) (time required for 75% w/w drug release) for solid dispersion was observed in different dissolution mediums. This was attributed to the formation of amorphous nature and intermolecular hydrogen bonding between drug and PVP K-30. The stability study showed there to be no significant change in molecular pharmaceutical properties and dissolution profile over the period of 3 months. Moreover, the in-vivo study in Wistar albino rats also justified improvement in the therapeutic efficacy of andrographolide after solid dispersion. This study demonstrates the utility of solid dispersion to improve primary and secondary pharmaceutical properties of andrographolide using PVP K-30 as a carrier.
    The Journal of pharmacy and pharmacology. 11/2009; 61(11):1465-72.
  • C. Bothiraja, M.B. Shinde, S. Rajalakshmi, A.P. Pawar
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    ABSTRACT: Objectives Andrographolide, a natural lipophilic molecule, has a wide range of pharmacological actions. However, due to low aqueous solubility, it has low oral bioavailability. The purpose of the study was to increase the solubility and dissolution rate of isolated andrographolide by formulating its solid dispersion. Method Solid dispersions were obtained by a spray-drying technique using different ratios of drug to polyvinylpyrrolidine (PVP K-30). Solid dispersions in compression with isolated drug and corresponding physical mixtures were characterized for various molecular pharmaceutical properties and subjected to stability study for up to 3 months. Key findings A five-fold increase in saturation solubility of andrographolide with higher values of Q5min (cumulative percentage release in 5 min) and lower values of t75% (time required for 75% w/w drug release) for solid dispersion was observed in different dissolution mediums. This was attributed to the formation of amorphous nature and intermolecular hydrogen bonding between drug and PVP K-30. The stability study showed there to be no significant change in molecular pharmaceutical properties and dissolution profile over the period of 3 months. Moreover, the in-vivo study in Wistar albino rats also justified improvement in the therapeutic efficacy of andrographolide after solid dispersion. Conclusions This study demonstrates the utility of solid dispersion to improve primary and secondary pharmaceutical properties of andrographolide using PVP K-30 as a carrier. Keywords andrographolide; amorphous; PVP K-30; solid dispersion; spray drying
    Journal of Pharmacy and Pharmacology 01/2009; 61:1465-1472. · 2.03 Impact Factor
  • C. Bothiraja, M.B. Shinde, S. Rajalakshmi, A.P. Pawar
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    ABSTRACT: Infections with the human immunodeficiency virus (HIV) are the most serious problems worldwide. Characteristic of an extracted medicinal plant is of great therapeutic significance. Emblica officinalis Linn is a valuable natural plant used in the South East Asian traditional medicine for different infection.. In this paper, aqueous extract of Emblica officinalis was prepared by cold maceration. The obtained dried extract was subjected to in-vitro anti HIV activity using viral p-24 assay as a criteria for the detection of viral load and antioxidant activity by using Beta Carotenelinoleate oxidation model. The aqueous extract (40 mg/100 ml) showed significant reduction in viral load as compared to control titer value and showed antioxidant activity. It is contributed by Flavonoids and polyphenols constituents. The results of the present study indicating that the aqueous extract of the Emblica officinalis can be used against Human Immunodeficiency Virus type 1. Being antioxidant, it can be used to prevent neurological diseases (damage of brain cell mitochondria ) by HIV.
    Research. J. Pharm and Tech. 01/2009; 2(3):556-558.
  • C. Bothiraja, M.B. Shinde, G.Y. Dama, S. Rajalakshmi
    The Indian Pharmacist. 01/2007; 66(6):21-24.
  • Indian journal of pharmaceutical education 01/2006; 40(6). · 0.30 Impact Factor