imaging technology can be applied to modify animal models to develop
fenugreek-based proactive ocular drug delivery systems.
11.3.2 Gastroretentive Drug Delivery
Gastric retention has been known as a key approach to increase the efficacy and
bioavailability of drugs having a slender absorption frame. Numerous drug delivery
strategies such as swellability, high density, floating and mucoadhesive machineries
have been fabricated to enhance the absorption and bioavailability of poorly gastroretentive drugs (Hao et al. 2014; Bera et al. 2015a, b; Deshpande et al. 1997).
Floating drug delivery system is one the most used strategy for gastorententive
drug delivery; however, one major disadvantage of this drug delivery system is its
dependency on gastric emptying/transit time (Deshpande et al. 1997). Different
strategies have been utilized to address this issue such as combining floating and
swelling approaches together (Chen et al. 2013). Floating and swelling behaviour of
drugs could be upgraded by applying polymer membrane on the gastroretentive
matrix (Deshpande et al. 1997). Polysaccharides extracted from the plants are used
as coating agents in gastroretentive drug delivery system as they possess key
pharmaceutical properties like stability, swelling and regulated drug release rate.
In this context, an efficient drug delivery system consisting of alginate-fenugreek
gum gel membrane covered with hydroxy-propyl-methyl-cellulose (HPMC) based
matrix containing quetiapine-fumarate (QF) drug for intra-gastric delivery was
developed. This formulation possesses improved buoyancy, prolonged drug release
and better swelling ability (Bera et al. 2015a, b). The presence of fenugreek-alginate
gel membrane on the surface of the tablet blocks many channels of core tablet,
which slow down the drug release rate (Bera et al. 2015a, b). Presence of an air
compartment between the coating layer and core tablet might be the reason for the
superior floating capability of the alginate-fenugreek gum-based formulation (Bera
et al. 2015a, b). Drawbacks such as weight gain and hyperglycemia associated with
QF therapy can be avoided using fenugreek gum (Bera et al. 2016). This study not
only proved that fenugreek gum as a potential natural polymer to be used in
targeted drug delivery system but also proposed an alternative approach to regulate
the disadvantages associated with QF therapy.
Though there are significant developments in gastro retentive drug delivery
systems formulations with meal independent gastric retention capacity, floating
behaviour is yet to be achieved. Fenugreek-based bioadhesive systems, super
porous hydrogels, floating systems, high density-based formulations and expandable systems may be acting as game changers in gastro retentive drug delivery
arena. Complex in vitro experiments can be designed to evaluate the efficiency of
fenugreek-based gastro retentive drug delivery systems by varying the density/
viscosity of gastric contents and providing a different degree of contractions in the
presence of food. The impact of pharmacokinetic property on gastric retention
ability can be observed using sophisticated in vivo imaging techniques.
388
P. Mishra et al.
fenugreek-based proactive ocular drug delivery systems.
11.3.2 Gastroretentive Drug Delivery
Gastric retention has been known as a key approach to increase the efficacy and
bioavailability of drugs having a slender absorption frame. Numerous drug delivery
strategies such as swellability, high density, floating and mucoadhesive machineries
have been fabricated to enhance the absorption and bioavailability of poorly gastroretentive drugs (Hao et al. 2014; Bera et al. 2015a, b; Deshpande et al. 1997).
Floating drug delivery system is one the most used strategy for gastorententive
drug delivery; however, one major disadvantage of this drug delivery system is its
dependency on gastric emptying/transit time (Deshpande et al. 1997). Different
strategies have been utilized to address this issue such as combining floating and
swelling approaches together (Chen et al. 2013). Floating and swelling behaviour of
drugs could be upgraded by applying polymer membrane on the gastroretentive
matrix (Deshpande et al. 1997). Polysaccharides extracted from the plants are used
as coating agents in gastroretentive drug delivery system as they possess key
pharmaceutical properties like stability, swelling and regulated drug release rate.
In this context, an efficient drug delivery system consisting of alginate-fenugreek
gum gel membrane covered with hydroxy-propyl-methyl-cellulose (HPMC) based
matrix containing quetiapine-fumarate (QF) drug for intra-gastric delivery was
developed. This formulation possesses improved buoyancy, prolonged drug release
and better swelling ability (Bera et al. 2015a, b). The presence of fenugreek-alginate
gel membrane on the surface of the tablet blocks many channels of core tablet,
which slow down the drug release rate (Bera et al. 2015a, b). Presence of an air
compartment between the coating layer and core tablet might be the reason for the
superior floating capability of the alginate-fenugreek gum-based formulation (Bera
et al. 2015a, b). Drawbacks such as weight gain and hyperglycemia associated with
QF therapy can be avoided using fenugreek gum (Bera et al. 2016). This study not
only proved that fenugreek gum as a potential natural polymer to be used in
targeted drug delivery system but also proposed an alternative approach to regulate
the disadvantages associated with QF therapy.
Though there are significant developments in gastro retentive drug delivery
systems formulations with meal independent gastric retention capacity, floating
behaviour is yet to be achieved. Fenugreek-based bioadhesive systems, super
porous hydrogels, floating systems, high density-based formulations and expandable systems may be acting as game changers in gastro retentive drug delivery
arena. Complex in vitro experiments can be designed to evaluate the efficiency of
fenugreek-based gastro retentive drug delivery systems by varying the density/
viscosity of gastric contents and providing a different degree of contractions in the
presence of food. The impact of pharmacokinetic property on gastric retention
ability can be observed using sophisticated in vivo imaging techniques.
388
P. Mishra et al.