Short Communication
Volume 4 Issue 5 - December 2017
DOI: 10.19080/OMCIJ.2017.04.555646
Organic & Medicinal Chem IJ
Copyright © All rights are reserved by Anju R Gupta
Aerosol-Ot Stabilized Micro and Nano-Scale
Emulsions for Pharmaceutical Formulations
Poornima Kalyanram
1
, Patricia Valenzuela
2
and Anju R Gupta
3
1
Soft Nanomaterials Lab, Kate Gleason College of Engineering, Rochester Institute of Technology, USA
2
Design Drafting - Gas Engineering, Southern California Gas Company, the Gas Company Tower, USA
3
Soft Nanomaterials Lab, Department of Chemical Engineering, Rochester Institute of Technology, USA
Submission: December 15, 2017; Published: December 18, 2017
*
Corresponding author: Anju R Gupta, Department of Chemical Engineering, Rochester Institute of Technology, 160 Lomb Memorial Drive,
Rochester, New York, 14623, USA, Tel: ; Email:
Introduction
Emulsions of micro and nano sizes are used in topical
applications for their increased bioavailability [1,2]. The smaller
size of the droplets provides more surface area resulting in
greater absorption of the pharmaceutical on the epidermal layer
[3,4]. Aerosol-OT (AOT) is an anionic surfactant and is widely
used as a stabilizer to form oil and water emulsions [5,6]. Due
to its biocompatibility, AOT is also used in drug delivery and
oral formulations and for the treatment of chronic constipation
[7-12]. The objective of this work is to form stable micro and
nano-scale emulsions which can potentially be used for drug
delivery and pharmaceutical applications. We used octane (C8)
and hexadecane (C16) as model organic phases to a) mimic
the mineral oil which is also used as a laxative lubricant and b)
demonstrate the ability of AOT to emulsify organics of different
molecular weights [13]. Many emulsions based studies reported
in the literature have used ethanol to stimulate the formation
of the emulsion droplets by reducing the surface tension of
water. Here, we report the formation of stable emulsions in the
absence of ethanol, which is highly desirable in drug delivery
and pharmaceutical applications. The resultant emulsions were
prepared with equal ratios (by weight) of oil to deionized water.
AOT constituted 60% by weight of the dispersant and was added
to octane and hexadecane in the presence and absence of ethanol.
Two different oil to water ratios-1:10 and 1:1 were tested. The
formation of emulsions droplets, their size and stability were
recorded by viewing them under an optical microscope for three
weeks. The presence of emulsified phase in the vials were also
visually inspected and reported through photographs in Figures
1 & 2. Table 1 summarizes the experimental test parameters
such as oil/water ratio, type of oil (organic phase) used, and the
resultant droplet size on Day 1 and Day 21 of the study.
Table 1: Experimental Matrix, Formulation Name and Size.
Oil Used
Ratio
of Oil to
Water
Presence
of Ethanol
Droplet
Size (Day
1)
Droplet
Size (Day
21)
Octane 1:1 Yes 48 nm 46 nm
1:1 No 158 nm 90nm
Hexadecane 1:1 Yes 6.95µm 7µm
1:1 No 7.5µm 8.8µm
Organic & Medicinal Chem IJ 4(5): OMCIJ.MS.ID.555646 (2017) 001
Organic and Medicinal Chemistry
International Journal
ISSN 2474-7610
Abstract
In this work we present the formation of micro- and nano-scale oil and water emulsion droplets stabilized by an anionic surfactant,
Aerosol-OT. The stabilizing effects of AOT were tested with high and low molecular organic phase (oil), and in the presence and absence of
ethanol acting as a co-solvent and emulsion enhancer. The key findings of this work are formation of -
a) Nano emulsions with lower molecular weight alkanes as the organic phase,
b) Micro emulsions in with higher molecular weight organic phase,
c) Stable emulsions over a period of 3 weeks in the absence of alcohol.
Keywords : Emulsions; Pharmaceuticals; Aerosol-OT; Octane; Hexadecane