The oral route is the utmost desired route for administration of drugs because of its easy and convenient way of non-invasive administration. It is also preferred because of its better patient compliance as compared to parenteral route. In order to be bioavailable, the drug must get absorbed by the human body and via oral route absorption occurs after drug dissolution by passive diffusion through the gastrointestinal (GI) membranes. Nearly 90% of drugs are administered through oral routes. The solubility of these drugs in aqueous medium governs functions like absorption and pharmacokinetic profile of the drug. Some of the best cosmetic science colleges in Maharashtra are conducting path-breaking research on bio-nanocomposites to boost their use in the cosmetic industry.
Various methods have been employed in order to increase drug solubility such as Salt Formation, Co-crystallisation and Co-solvency, Hydrotropic, Solubilising agent and Nanotechnology by Chemical modification. Under Physical Modifications, the particle size reduction, modification in the crystal habit, complexation, solubilisation by surfactants and drug dispersion in carriers. The BCS is a predictive tool with the help of which drugs can be categorised based on its GI absorption.
In BCS, the drugs are classified based on permeability through GI cell wall and solubility in aqueous medium which is responsible to give required bioavailability in the human body. The drugs which belong to class II and IV have poor aqueous solubility and are difficult to design in formulation, based on physicochemical and biopharmaceutical properties for oral administration. Dissolution of a crystalline solid is an energy-driven step process. Each step requires a certain amount of energy to be completed; the target of drug solubilisation is to lower the overall required energy. In general, the kinetics of the process depends on solute and solvent chemical nature and microstructure, and on the system conditions.
Nanoparticles in Drug Delivery
Nanoparticles are solid particles or dispersions with a size ranging from 10-1000 nm. This drug is entrapped or adhered or dissolved in or on the polymer matrix. Depending upon the method of preparation nanospheres or nanocapsules were obtained. In nanocapsules the drug is confirmed or embedded in the cavity of a polymer membrane, whereas in nanospheres the drug is physically or uniformly dispersed. Apart from the structure, nanocapsules differ from nanospheres in their size and degree of polymerisation. Nanocapsules are generally larger than nanospheres and degree of polymerisation is higher in nanocapsules than nanospheres. Nanospheres are more easily lyophilised than the nanocapsules because nanocapsules are easily collapsed by freeze drying.
Use of Natural Carriers in BNC’s
Biopolymers have been used as drug carrier substrates in the past with several studies examining materials, such as sodium alginate, chitosan and gelatine resulting in formation of three-dimensional (3D) structure. In recent years, carbohydrate polymers are widely used in biomedical and pharmaceutical applications because of their biodegradable and biocompatible nature. The polysaccharides on the other hand are one of the richest industrial raw materials and are subjected to thorough research due to their bio-safety, biodegradability, and sustainability.
Different types of natural–origin carriers, especially polysaccharides and proteins that are used in research, or might be possibly useful as carriers for active components as well as biomolecules with application in enhancement of solubility and targeting of various biological tissues. Combination of above given applications into a single material has resulted to be very challenging.
Microwave Induced Diffusion (MIND) Technology
By using silicon dioxide as the substrate for drug adsorption, however, drug recrystallisation was encountered as a major problem due to the high mobility of drug molecules on inorganic surfaces. Replacement with inert 3D matrixes such as cyclodextrin and crospovidone which have appropriate microstructural properties for avoiding drug recrystallisation. The use of bio carriers in dissolution and solubility enhancement is a pioneering concept. Use of natural carriers as a composite material for incorporating drugs in the nanocrystalline form with the aid of microwave-induced diffusion (MIND), which is a green and effective way of generating nanocomposites.
The bio carriers for BNCs are acacia gum, ghatti gum, cassia gum and gelatine, or some other reported polymer. The selection of the carriers is done on the basis of their surfactant and wetting properties, which furthermore support solubility enhancement and dissolution and eventually bioavailability. Gelatine is a natural protein carrier that has a good dielectric property, the remaining carriers are carbohydrates, which also have good dielectric properties, indicating excellent efficacy of molecular heat transfer required for MIND (microwave induced diffusion).
Need and Objectives
Need
The poor dissolution characteristics of relatively insoluble drugs have long been a problem to the pharmaceutical industry. The solubility characteristic of a drug is a good indicator of gastrointestinal absorptivity. Poorly soluble drugs are characterised by low absorption and weak bioavailability. For such drugs, there is a need to find appropriate formulation approaches to improve aqueous solubility and thus bioavailability.
Objectives
Primary objective is to enhance the solubility and dissolution rate by formation of bio nanocomposites using natural polymer such as gelatine having low viscosity and low swelling properties.
Conclusion
The use of natural gums and polymers was made as they are non-toxic, biodegradable and very economical. Hence nowadays the use of natural polymers in the development of drug delivery in the pharmaceutical industry is very prominent and exhaustive. As reported the GLT, ACC, GG and CG have surfactant activity and also increases wetting by reducing the contact angle, thus enhancing the solubilisation and dissolution of drug particles. Pursuing a B.Sc in Cosmetic Science can further enhance your understanding of bio-nanocomposites and their applications in the cosmetics industry.
Polymers used in present studies have low viscosity as well as low swelling and have the ability to form the matrix which can be utilised for formation of BNC’s. This bio nanocomposite has good solubility and dissolution enhancement due to reduction of crystallinity as nanocrystals are formed. Additionally, the microwave treatment is a very green, effective and advanced way for formation of BNC’s.
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