Journal of Sol-Gel Science and Technology

, Volume 61, Issue 1, pp 161–168 | Cite as

Sol–gel behavior of a novel nanodroplet biomaterial for drug delivery

  • K. Pramod
  • S. Shanavas
  • Shahid H. Ansari
  • Javed Ali
Original Paper


Nanodroplets can be considered as those nano/microemulsions in which the oil itself forms the active agent and the droplet size ambits in the nanometer range. Eugenol is an anti-inflammatory agent and its nanodroplet gel (NDG) has immense potential for topical use. Topical gels oblige some rheological characteristics to nail down the demands of proper application, stability and storage. Thus, the purpose of our study was to comprehend the effect of eugenol on the sol–gel tranisition properties of its NDGs. Towards this goal nanodroplets of eugenol were prepared and evaluated and the three selected nanodroplet formulations with 5, 10 and 5% v/v eugenol were converted into topical gel formulation using 1% w/w Carbopol 940. The NDGs were characterized using frequency sweep, creep recovery and thixotropy. All these tests pointed out that eugenol concentration has significant effect on the sol–gel behavior of NDGs. The NDGs exhibited more viscous (sol) properties than elastic (gel) properties as observed from the frequency sweep studies. The thixotropy of the NDGs was found to decrease with increase in eugenol concentration. Efforts have been made to explain the study results using mechanistic approach. The outcomes of our research studies could be of great use in future endeavors towards development of a topical NDG of eugenol with tailored sol–gel behavior.


Eugenol Nanodroplet Frequency sweep Creep recovery Thixotropy 



Mr. Pramod K gratefully acknowledges Indian Council of Medical Research (ICMR), New Delhi, India, for providing Senior Research Fellowship (No. 35/3/10/NAN/BMS).


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • K. Pramod
    • 1
  • S. Shanavas
    • 2
  • Shahid H. Ansari
    • 3
  • Javed Ali
    • 1
  1. 1.Department of Pharmaceutics, Faculty of PharmacyJamia HamdardNew DelhiIndia
  2. 2.Starch Characterization Laboratory, Division of Crop UtilizationCentral Tuber Crops Research InstituteThiruvananthapuramIndia
  3. 3.Department of Pharmacognosy and Phytochemistry, Faculty of PharmacyJamia HamdardNew DelhiIndia

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