Drug administration is the process of administering drugs containing pharmaceutical components to achieve a therapeutic effect in humans. This is a drug delivery method. Oral, topical, transmucosal (nasal, buccal, sublingual, vaginal, ocular, and rectal), and inhalation routes are typical drug delivery techniques.
A new method of drug administration that differs from traditional drug delivery systems is known as a “novel drug delivery system.” Day by day, new, innovative drug delivery systems are being created to deliver drugs to specific sites for increased effectiveness and fewer side effects. Drug targeting systems are being developed to reduce drug loss and degradation, avoid side effects, and increase bioavailability while maintaining therapeutic value.
Because of limitations in conventional drug delivery and formulation, such as higher doses, undermined effectiveness, side effects, etc., these alternative techniques are needed to navigate the limitations of the traditional drug delivery system.
Concept Of The NDDS
A novel drug delivery system is a new method of drug delivery. To safely achieve the desired therapeutic effects of a pharmaceutical compound, a “novel drug delivery system” (NDDS) refers to the methods, formulations, technologies, and systems for achieving this goal.
New drug delivery systems were created in response to the need to provide medications to patients effectively, with fewer side effects and greater efficacy. Designing NDDS considers physical and biochemical mechanisms. Diffusion, osmosis, and dissolution are examples of physical mechanisms. Gene therapy, liposomes, nanoparticles, and monoclonal antibodies are examples of biochemical.
Types Of NDDS
- Targeted Drug Delivery System
- Sustained drug delivery System
- Controlled Drug delivery system
1) Targeted Drug Delivery System
Target a site-specific area to achieve desired effects while lowering side effects.
The dosage form and administration route have a direct impact on how effectively a drug is presented.
A targeted drug delivery system is a method of delivering medications to a targeted organ or site of action. Targeted drug delivery seeks to concentrate the medication in the tissues of interest while reducing the relative concentration of the medication in the remaining tissues. This method is important to achieve a desired pharmacological response at selected sites without undesirable interaction at the other sites so that the drug has a specific action with minimum side effects and a better therapeutic index.
Advantages of TDDS:-
- Toxicity is reduced by delivering a drug to its target site, thereby reducing harmful systemic effects.
- Drugs can be administered at a smaller doses to produce the desired effects.
- Enhancement of the absorption of target molecules such as peptides and particulates
- The dose is lower compared to conventional drug delivery systems.
- Selective targeting of infection cells that compare to normal cells
Carriers: Carriers are the molecules or systems required for the effective transportation of loaded drugs up to the selected site.
1. Polymers: Polymers are defined as very large molecules having a high molecular mass that is formed by the joining of repeating structural units on a large scale. It is used as a coating material (ex. HPMC Methylcellulose, polyethene glycol), as a binder in tablet granulation (ex. acacia, sodium alginate, starch paste), and as a thickening agent.
2. Microcapsules: Microencapsulation is a process by which solids, liquids, or even gases may be enclosed in microscopic particles formed by the thin coatings of wall material around the substance.
Microencapsulation gives us the power to change colloidal and surface properties, protect the environment, and regulate the release characteristics or availability of coated materials.
Microcapsules contain an active agent and a polymeric shell or are surrounded by a polymeric shell or are dispersed in a polymeric matrix. Microcapsule size changes from 1 to 1000 microns. Microcapsules can have different structures.
Microencapsulation can stabilize medications that are susceptible to oxygen, moisture, or light. To lessen toxicity and GI irritation, many medications, including ferrous sulphate and KCl, have been microencapsulated.
3. Microparticles: small spherical particles (also known as small spherical particles or microspheres). The diameter ranges from 1 micron to 1000 microns. It can be made using various materials. e.g., polymer, glass, ceramic.
Microspheres are naturally biodegradable powders made of proteins or synthetic polymers that typically flow freely and have a particle size of fewer than 200 micrometres.
Several amphiphilic compounds have been employed to create liposomes.
4. Lipoproteins: A lipoprotein is a biochemical assembly that contains both proteins and lipids, bound to the proteins, which allow fats to move through the water inside and outside cells. The lipid molecule is emulsified by the protein. Many enzymes, transporters, structured proteins, antigens, and toxins are lipoproteins.
5. Liposomes: Liposomes are simple microscopic vesicles in which an aqueous volume is entirely composed of a membrane of lipid molecules.
To develop liposomes, many amphiphilic compounds have been applied.
Various amphiphilic molecules have been used to form liposomes. The drug molecule can either be encapsulated in an aqueous space or intercalated into the lipid bilayers. These are uni flagellar or multilamellar phospholipid vesicles composed of concentric spherical layers of aqueous zones sandwiched between phospholipid membranes. The extent of drug location will depend upon its physicochemical characteristics and composition of lipids.
Drugs such as Amphotericin B, Doxorubicin, and Daunorubicin have been successfully launched on the market as liposomes. PEGylated liposomes have applications as stealth vehicles for prolonged and targeted drug delivery.
6. Niosomes: Niosomes are non-ionic surfactant vesicles that can entrap both hydrophilic and lipophilic drugs either in the aqueous phase or in a vesicular membrane made up of lipid materials. It is reported to attain better stability than liposomes, hence having greater interest in industrial adoption. They have been reported to be useful as targeting systems for drugs for the treatment of cancer and in the therapy of microbial diseases caused particularly by viruses and parasites. Other drugs such as sodium stibogluconate, doxorubicin, and etoposide are used systemically, as are certain dermal therapeutic agents such as 5-dihydrotestosterone, triamcinolone acetonide, etc.
It may prove very useful for targeting the drugs to target cancer, parasitic, viral, and other microbial diseases more effectively.
7. Micelles: Micelles are lipid molecules that arrange themselves in a spherical form in an aqueous solution. Amphiphilic molecules form micelles. A micelle is an aggregate of monomer surfactant molecules dispersed in a liquid colloid.
2) Sustained Drug Delivery System
The hydrophobic tail areas in the micelle center are situated between the hydrophilic head regions that are in contact with the surrounding solvent. Sustained-release drug delivery system:
Drug delivery systems are designed to achieve prolonged therapeutic effects by continuously releasing medication over an extended period after administration of a single dose the basic goal of therapy is to achieve a steady-state blood level that is therapeutically effective and nontoxic for an extended period of time. The design of a proper dosage regimen is an important element in accomplishing this goal. Sustain release dosage forms are defined as the types of dosage forms in which a portion of the drug is released immediately to achieve the desired therapeutic response.
Prolonged release implies that the medicine will release slowly over time. The emission is either controlled or not.
Control of drug action by formulation also means that this is usually concerned with maximizing drug availability by trying to achieve a maximal rate and amount of drug absorption.
Advantages: Avoid problems with drugs that have a narrow therapeutic index (a small difference between their toxic and therapeutic levels).
Systems provide medications over an extended period with the goal of maintaining therapeutic blood levels.
3) Controlled Drug Release Drug Delivery System
Controlled drug delivery is a type of system that releases the medicaments from the dosage form at a predetermined rate, either locally or systematically, for a specified period of time.
A drug is generally derived in a zero-order sequence to maintain constant drug levels in the blood and target tissues.
Controlled drug delivery is one that delivers the drug at a predetermined rate, either locally or systemically, for a specified period.
Controlled drug delivery systems can include the maintenance of drug levels within a desired range, the need for fewer administrations, optimal use of the drug in question, and increased patient compliance.
Advantages of CDDS:
- A low amount of administered doses.
- Less dosing frequency.
- improved patient acceptance and compliance.
- Enhanced efficacy and drug safety.
- Diffusion: In diffusion-controlled delivery systems, rate control is obtained by the penetration of fluids into the system.
- Dissolution matrix: solid substances solubilize in a given solvent. mass transfer from solid to liquid.
- Diffusion and Dissolution Matrix
- Osmotic pressure-controlled matrix: Osmotic a
- Chemically controlled drug delivery system
- Hydrogen drug delivery system
- ION exchange resin drug delivery system
Need For NDDS Drugs
Pharmaceutical companies are focusing heavily on designing and formulating medications and delivery dosage forms to get around the drawbacks of traditional delivery systems. A novel drug delivery system is required to keep the drug concentration within the therapeutic effective range. This technology aids in enhancing effectiveness and minimizing side effects. Increasing the therapeutic window is necessary to maximize the benefits of the drug being administered.
This development concentrated on the requisite site because it was more effective. Drugs are being developed by NDDS to increase this bioavailability. The level of drug concentration in plasma is known as bioavailability. Due to the possibility of enzymatic degradation, many medications, including peptides, proteins, antibodies, vaccines, and gene-based drugs, may not be taken via conventional routes. The enzymes and proteins that enter the body after a drug administration may cause the drug to disintegrate; therefore, we must administer a drug that is site-specific.
The limitations of conventional drug delivery methods are resolved by the innovative drug delivery system, which is a novel method of drug administration.
Modern medicine may treat a specific ailment by precisely locating the diseased location within a patient’s body and delivering the treatment there.
- Lower the dose frequency (the dose frequency is
- Improve patient compliance.
- The rate of release slows.
- To reduce side effects
- Enhanced efficacy and safety
- Accurate dosing
- Site-specific delivery of drug
Factors Affecting The Drug Products
Aqueous Solubility: Aqueous solubility means the solubility of substances in water. A drug substance cannot be absorbed without aqueous solubility.
Partition Coefficient: The measure of the lipophilicity of a drug and an indication of its ability to cross the cell membrane. Partition coefficients describe how a solute is distributed between two immiscible solvents.
Drug Stability: It refers to the capacity of a drug substance or product to remain within established specifications of identity, strength, quality, and purity for a specified period. Drug stability is directly proportional to drug efficacy.
Stability is officially defined as the time lapse during which the drug product retains the same properties and characteristics that it possessed at the time of manufacture. The drug should be stable under climatic conditions.
Molecular size: The molecular size of a drug affects its solubility. Therefore, the larger the molecular size, the lesser the solubility. As more solubility gives more effect on drug medicaments, many medications with poor solubility have had their absorption increased using particle size reduction.
Absorption: Drug absorption is the passage of a drug from its site of administration into circulation. The process of movement of an unchanged drug from the site of drug administration to the systemic circulation Medications can enter the body through various routes of administration.
The level of absorption is referred to as bioavailability.
Drug distribution refers to the movement of drugs to and from the blood and various tissues of the body (for example, fat, muscle, and brain tissue) and the proportion of medication in various tissues. The extent of drug distribution depends on its lipid solubility, ionization at physiological pH, the extent of binding to plasma and tissue proteins, and differences in regional blood flow due to diseases like CHF, uremia, and cirrhosis.
Elimination: Drugs are removed from the body by various elimination processes. Elimination includes metabolism and excretion. Metabolism consists of the anabolic (building up) and catabolic (breaking down) metabolism of substances by enzymatic conversion of one chemical entity to another within the body. Excretion is the bodily elimination of a chemically unchanged drug or its metabolites.
Dose size: The quantitative amount administered to or taken by a patient for the produced medicinal effects. Quantitatively, drug doses vary greatly among drug substances; some drugs have small doses, while others have relatively large doses.
Therapeutic window (the difference between effective and minimal adverse effects).
A medicine generally runs the risk of being ineffective at low concentrations, while the risk of negative consequences increases at high concentrations.
Dosing regimens are devised to maximize effectiveness and reduce negative effects while keeping medication concentrations within therapeutic windows.
Patient physiology: The physiology of the patient greatly affects medication. The response of the body to the drug is also important
Microparticles: A large spectrum of drugs have been modulated for release and other properties, e.g., theophylline, vitamin C, cardiovascular drugs, antipsychotics, antibacterial, and chemotherapeutic agents, to name a few therapeutic classes of drugs.
Nanoparticles: Nanoparticles have been utilized to deliver and control the release of drug molecules from suitable polymeric nanoparticles or nanospheres. Usually, FDA-approved biocompatible polymers such as poly epsilon-caprolactone, chitosan, and poly alkyl cyanoacrylates have also been used.
A few medications, including Amphotericin B, have been solid Nanoparticulate systems. Additionally, some antineoplastic, proteins, peptides, and macromolecules have been studied in animal studies and clinical studies.
Liposomes: Liposomes showed immense potential in the delivery of anti-tumour therapeutics as well as anti-fungal agents. Drugs such as Amphotericin B, Doxorubicin, and Daunorubicin have been successfully launched on the market as liposomes.
Transdermal drug delivery system
Future Of NDDS
The future of research will be focused on developing the ability to deliver drugs to targeted regions of the body. Most of the development work on NDDS has been on small molecules.
In the future, NDDS will be used extensively in the treatment of chronic illnesses and pain.
The level of safety awareness is increasing, and at that point, localization of the goal becomes crucial.
Here is a specific antibody or carrier that could potentially be targeted toward the tumour, and this antibody or carrier will take the drug along with it. There will also be a growing need for hormone replacement therapy products using NDDS as the population ages. You can have fancy technologies that helped in commercially bringing out some products on the market. These two significant advances have set the tone for NDDS research and development.
The difficulties have mostly come from the perspectives of the manufacturing and delivery systems; they have more to do with drugs’ prolonged periods of activity.
There will be a transition from NDDS to ADDS (advanced drug delivery system).
There may not have been any original technologies created, but there is undoubtedly an effort being made to innovate with and enhance existing legacy technologies.
A strategy that could allow active targeting involves the surface functionalization of drug carriers with ligands that are selectively recognized by receptors on the surface of the cells of interest.
For over 20 years, researchers have appreciated the potential benefits of nanotechnology in providing vast improvements in drug delivery and drug targeting.
Improving delivery techniques that minimize toxicity and improve efficacy offers great potential benefits to patients and opens new markets for pharmaceutical and drug delivery companies.
Top 13 Interesting Facts About NDDS
Microencapsulation can aid in the stabilization of medications that are sensitive to oxygen and moisture.
Lipoproteins allow fats to circulate via water both within and outside of cells.
Liposomes are tiny vesicles with aqueous volumes that are entirely composed of lipid molecule membranes.
Micells are lipid molecules found in aqueous solutions.
The level of drug concentration in plasma is referred to as bioavailability.
The partition coefficient describes the distribution of a solute between two immiscible solvents.
The first transdermal medicine delivery method was introduced about 20 years ago.
The Atrigel system is a proprietary drug delivery device that can be utilized for parenteral and site-specific medication administration.
Nanotechnology is capable of penetrating medications into areas to kill malignant cells.
Homogenization and ultrasonication were used to create solid lipid nanoparticles.
Drug-encapsulated nanoparticles are solid colloidal particles ranging in size from 10 to 1000 nm.
Folate-conjugated radiopharmaceuticals are used to target cancer tissue.
Radiolabel-led biologics have the potential to improve the treatment of rheumatoid arthritis.