The study formulated and evaluated clarithromycin-loaded niosomal formulations for in vitro and in vivo behavior. Various niosomal formulations were prepared using different ratios of spans and cholesterol. Solubility studies found the drug most soluble in dichloromethane and least soluble in PBS. Optical and electron microscopy showed the particles were spherical and smallest for Span 80. Span 60 formulations had the highest drug entrapment. In vitro studies found Span 60 released 96.78% of the drug over 24 hours. Zeta potential was highest for Span 20 and lowest for Span 60. The study concluded niosomal formulations provide sustained delivery of the drug with enhanced bioavailability and could reduce side effects of

1. Guided by: Kilor Maam
Prepared by: Hasan Hussain

3.  The study was focused on formulating and
evaluating clarithromycin (CLR) containing
niosomal formulation for in vitro and in vivo
pharmacokinetic behavior. Niosomal
formulations (empty and drug loaded) were
prepared by using different ratio of surfactant
(various Span grades 20, 40, 60, and 80) and
cholesterol by thin film hydration method and
were evaluated for in vitro characteristics,
stability studies, and in vivo study. Dicetyl
phosphate (DCP) was added to the niosomal
formulation.

4. Determination of Solubility of CLR
Solubility of drug was determined in various solvent
such as PBS 7.4, acetone, methanol, ethanol,
dichloromethane, and chloroform. For this, an
excess amount of drug was transferred to 50mL
volumetric flasks containing 25mL of solvent. The
volumetric flasks were securely capped and placed
in the mechanical shaker water bath at 25∘C for 24
hr and then sonicated for 10min, and thus
sufficient time was provided for contact to produce
saturated solutions. Solutions were filtered by
passing through a 0.45 𝜇m membrane filter and
analyzed on UV spectrophotometer at 265 nm.

5. Sr. number Solvents Solubility (mg/mL)
1 PBS 7.4 0.11 ± 0.005
2 Acetone 74 ± 1.2
3 Methanol 67 ± 0.2
4 Ethanol 63 ± 0.2
5 Dichloromethane 221 ± 1.4
6 Chloroform 18 ± 0.6

6.  Preparation of Niosomal Formulation
In the present study, niosomal formulations
were prepared by thin film hydration
technique with slight modifications by using
different grades of Span (Span 20, Span 40,
Span 60, and Span 80) at various cholesterol :
surfactant ratios, that is, 0.5 : 1, 1 : 1, 1.5 : 1,
1 : 0.5, and 1 : 1.5. DCP was added to the
formulation that acts as a negative charge
inducer which provides more efficient drug
delivery and keeps the niosomal formulation
stable for long period of time.

7. Particle Shape and Morphology
Shape and morphology of empty niosomal
formulations and drug loaded niosomal
formulations were determined by optical
microscopy and Transmission Electron
Microscopy (TEM) and results were shown in
Figures 1 and 2.

8. A) Span 20
(B) Span 40 (C) Span 60 D) Span 80
(A) Span 20 (B) Span 40 (C) Span 60
(D) Span 80
Optical microscopy of niosomes. (a) Empty and (b) drug
loaded at 45x magnification.

9.  A drop of niosomes suspension was placed on a
glass slide. A cover slip was placed over the
niosomes suspension and evaluated the average
vesicle size and shape by an ordinary optical
microscope using a precalibrated ocular eye piece
micrometer Mean particle sizes of all empty
niosomes formulation and drug loaded niosomal
formulations were determined by using optical
microscopy.
 The particle sizes of niosomes were decreased
consistently from Span 20 to Span 80 and are
found in the following order:
 Span 20 > Span 40 > Span 60 > Span 80.

10.  Entrapment efficiency is the percentage
fraction of the entire drug entrapped in the
niosomes.
 Span 60 > Span 40 > Span 80 > Span 20.

12.  On the basis of particle size and entrapment
efficiency, suitable niosomal formulation was
selected for In vitro drug releases’ studies. In vitro
studies of selected formulations were carried out
by dialysis method on magnetic stirrer. It was
clearly observed that in vitro drug release of
niosome containing Span of different series (60
and 80) was sharply increased up to 24 hr.
Maximum drug release, that is, 96.78%, was
reported in case of niosome containing Span 60 as
compared to other series of Span 80 after 24
hours. This might be due to longest alkyl chain
length of Span 60 and thus possesses highest
release profile.

13. Zeta potential was determined by using Zetasizer.
It was clearly observed that highest zeta potential
was observed with Span 20 whereas lowest zeta
potential was in case of Span 60. This might be due
to increases in hydrophilicity of surfactant.
Sr. number Formulation Zeta potential
1 Span 20 −31.12
2 Span 40 −29.67
3 Span 60 −24.93
4 Span 80 −26.62

14.  The findings revealed that the process
variables critically affect the formulation of
niosomes with regard to drug loading and
need to be carefully controlled. In conclusion,
study suggests that these niosomal
formulations provide sustained and
prolonged delivery of drug with enhanced
bioavailability. The niosomal formulation
through pulmonary route could be a useful
dosage form to reduce the undesirable side
effects associated with oral route.

15. Thank You