INTRODUCTION:

Protein is derived from a Greek word “Proteios” Means Holding the first Place. Proteins are the high molecular weight mixed polymer in which amino acids are joined together by the Peptide Linkages. Protein mainly contains Carbon, Nitrogen, Oxygen and Sulphur Molecule. These Peptide and Proteins are present abundantly in Living system and Biological cell.^1-2 In human being it act as Enzymes, Hormones, Immunoglobulin’s and Structural Elements³ Proteins have the body building ability. It gives a definite shape, strength to the cell and tissues⁴ It plays an important role in immunogenic defense, several biological activities and metabolic process like regulation Osmotic Pressure, pH, and Temperature in the body.⁵ Examples of some protein hormone and its use:

1. Insulin is a protein hormone. It regulates the Blood sugar level⁷

2. Erythropoetin is also protein which regulates the erythropoiesis.⁸

3. Oxytocin is a protein hormone used in management of labor pain.⁹

4. Plasminogenis the protein and use as tissue activator in Heart attack, Stroke.⁹

5. Bradykinin increases the peripheral circulation.⁹

6. Somatostatin decrease bleeding in gastric ulcer.⁹

7. Gonadotropin induce ovulation.⁹

Need of protein drug delivery system:

Recombinant forms of protein hormone can be manufactured biotechnologically and are using by Pharmaceutical and medical practices in the management of various serious condition. No oral formulations of protein drugs are available in the market. As the Protein drugs are the biological drug when it given orally, it comes in contact of various enzymes and bacterial flora present in the gastrointestinal tract (GIT). It causes the degradation of protein complex in the acidic and protease-rich environment of the GIT. High molecular weight of protein drugs often results in poor absorption into the periphery when administered orally.

Various obstacles are there in the way of Oral drug delivery of Protein drug.

1. Enzymatic barrier: The gastrointestinal tract has a variety of enzymatic barriers. Protein drugcan be degraded by intracellular enzymes, bacterial flora and proteolytic enzymes. These enzymes denature protein drugs.¹⁰

2. Physiological barrier: The epithelial cells of the gastrointestinal tract are tightly bound by tight junctions in which the outer surface of the intestinal epithelium is coated by mucus and glycocalyx layers, and thus inhibits the passage of Protein drugs and its subsequent absorption¹¹

3. Physicochemical properties of Protein drug: The large molecular size of Protein drug remains an obstacle to its absorption¹². Macromolecular proteins normally cannot cross the intestinal epithelium. They will instead be degraded in the gastrointestinal tract before absorption¹³ Thus, protein drugs available are in parenteral form. Most of the proteins drug have a short serum half-life thus it needs to be administered frequently or in high doses to achieve the therapeutic effectiveness. Frequent dosing of these drugs by injection make patient uncomfortable and cumulative doses also may produce severe side effect due to unspecific binding of drug to non-targeted tissue.¹⁴ It is very serious need of oral drug delivery system for protein drugs; many of the researchers are working to develop oral drug delivery system for protein drugs. Various researches proven that nanoparticulate carriers such as polymeric nanoparticles and micelles are employed for the oral delivery of protein drugs. Nanotechnology has the potential to improve patient quality of life through decreased administrations due to longer drug release profiles and decreased side-effects due to reduced concentrations of toxic medications and targeted delivery. Polymeric nanoparticles are the most suitable for the protein drug due to their biocompatibility and non-toxic nature.¹⁵ Thus, there is need to develop nanoparticulate oral drug delivery system for protein drug in which protein drug encapsulated in polymeric nanoparticles.

Nanotechnology is a rapidly expanding field, encompassing the development of man-made materials in the 5-200 nanometer size range. Absorption of drug molecules depends on the particles in gastrointestinal tract (GIT) which occurs through various sites and depending upon their size. Particles size with 1 µm diameter are absorbed via phagocytosis by intestinal macrophages while particles <10µm in diameter are transported through Peyer’s patches (lymphatic islands present on GIT). Nanoparticles (<200 nm) are absorbed through endocytosis by enterocytes.¹⁶ The efflux transporters such as P-glycoprotein (Pgp) and enzymes, expressed on enterocytes surface, also render the low systemic bioavailability of drugs affecting the absorption and excretion of drugs.¹⁷ Nanotechnology is delivering systems for the active ingredient of the medicine. Effective nanomedicine must be stable, biodegradable, non-toxic, non-inflammatory, non-thrombogenic, nonimmunogenic and should escape by reticuloendothelial system^18,19 It has been proved experimentally that, for therapeutic and imaging applications, nanoparticles may range from 2 to 1000 nm should be applicable to different molecules such as small drugs, proteins, vaccines or nucleic acids.^20,21

Incorporating protein drug in polymeric nanoparticles having the certain benefit^22-29 like

1. The drug can be protected from biochemical degradation.

2. Targeted delivery through enhanced permeability and retention.

3. Extending in vivo half-life.

4. Providing prolonged drug release.

5. Reducing side effects.

6. Reducing administration frequency and lowering drug dosage.

7. Enhance therapeutic effectiveness without frequent administration.

8. Avoid poor patient compliance

9. Reduction of drug toxicity and side effects.

Approaches for Nano Particulate Drug delivery system:

Nanocarriers have immense potential for the effective oral delivery of protein drug. Designing nanocarriers to improve erythropoietin gastrointestinal absorption may be achieved via modifying the polymer or nanoparticles surface property and applying an enteric coating onto the nanoparticles.

1. Polymeric Nano carrier approach: The polymeric nanoparticles are an approach to improve protein drug absorption from the gastrointestinal tract. Synthetic or natural polymeric materials modulate protein drug release and consequent pharmacological activity. Nanoparticles loaded with protein drug can be prepared by using biodegradable polymers such as Chitosan, poly (lactide-co-glycolide), poly anhydride, and poly alkyl cyanoacrylate are absorbed from the intestinal epithelial cells and transport erythropoietin through the intestinal mucosa³⁰ Incorporating erythropoietin in polymeric nanoparticles having the certain benefit like

· The incorporated drugs can be protected from biochemical degradation.

· Targeted delivery through enhanced permeability and retention.

· Extending in vivo half-life.

· Providing prolonged drug release; augmenting drug efficacy.

· Reducing side effects.

· Reducing administration frequency and lowering drug dosage.

· Enhance therapeutic effectiveness without frequent administration.

· Avoid poor patient compliance

· Reduction of drug toxicity and side effects.

2. Enteric coating approach: The enteric coating technique has been applied for oral delivery of protein drug in which the enteric coating polymers possess a pH dependent property³¹ Polyacrylic polymers (e.g., Eudragit L100-55 and Eudragit S100) and cellulosic polymers (e.g., Hydroxy propyl methyl cellulose phthalate) have been widely used for this purpose³² The increase in erythropoietin bioavailability is achieved by filling the freeze-dried chitosan/poly (g-glutamic acid) (CS/g-PGA) nanoparticles in enteric coated capsules.

The enteric-coated capsules protect the protein drug loaded nanoparticles from acidic gastric fluid and rapidly liberate erythropoietin in the proximal segment of the small intestine. Thus, the absorption of protein drug into systemic circulation is improved and the relative bioavailability of protein drug will increase³³.

3. Enzyme inhibitor approach: protein drug can be digested and inactivated by digestive enzymes in the stomach after oral administration. Different protease inhibitors areadministered along with the nanoparticles to inhibit the activity of these enzymes³⁴ Radwan and Aboul-Enein³⁵ reported that the oral administration of insulin (Protein drug)-loaded poly(ethylcyanoacrylate) nanoparticles in the presence of protease inhibitors (e.g., glycerrizin, capric acid, deoxycholic acid, hydroxypropyl-bcyclodextrin, and aprotinin) efficiently reduces and maintains glucose level < 200mg/dL (i.e., the normal glucose level after a meal). Another approach to inhibit protease activity is by use of cationic metal chelating agents such as diethyl enetriaminepenta acetic acid (DTPA)³⁶. The addition of the complexing agent DTPA in insulin nanoparticles demonstrates a substantial protective effect against intestinal proteases in which the DTPA binds to cofactors [e.g., calcium (Ca2þ) and zinc (Zn2þ)] of the enzyme system and cause structural alterations and the loss of enzymatic activity.

4. Permeation enhancers approach: The absorption of protein drug from the gastrointestinal tract is improved by the coadministration of permeation enhancers that widen the intercellular junction (e.g., paracellular pathway) and/or perturbate the membrane phospholipids (e.g., transcellular pathway)³⁶ Permeation enhancers which include fatty acids, surfactants, Ca2þ-chelating agents, and zonula occludestox7in dare incorporated in the formulations.

Designing of a protein and peptide drug for delivery though GI tract requires a multitude of strategies.

Steps to be Involve in the Development of Nanoparticulate oral Drug delivery of Protein Hormone:

1. Cogugation of ligand to polymers:

Various researches shows that after conjugation of ligand to polymer, increase the permeability of nanoparticles across the epithelial cell of intestine. Jain A. et. al. 2015 was formulated L-Valine appended PLGA nanoparticles for oral insulin delivery which found that the small intestine has been shown to be able to transport the L-form of amino acid against concentration gradient. So, L-Valine was used as a ligand for carrier mediated transport of Insulin loaded polylactic-co-glycolic acid (PLGA) nanoparticles³⁶. MatejaCegnar, Barbara Podobnik, PorekarVladkaGaberc, StagojMateja Novak, Spela JALEN, Radovan Komel, Simon CASERMAN was studied thaterythropoietin (EPO) conjugates having a high bioavailability and efficacy, especially when administered perorally³⁸.

2. Preparation of Nanoparticles by using conjugated polymer.⁸

Different methods can use for the Methods of Preparation for Nanoparticles:

1. Emulsion Solvent Evaporation Method: This method is use most frequently used methods for the preparation of nanoparticles. Emulsification solvent evaporation methods: It includes two steps. First step involves emulsification of the polymer solution into an aqueous phase. In the second step polymer solvent is evaporated, and polymer precipitation as nanospheres. Nanoparticles are collected by using ultracentrifugation process. After centrifugation residue wash with distilled water. Size of nanoparticles can be control by adjusting the stirring speed, type and amount of dispersing agents, temperature, viscosity of organic and aqueous phases.

2. Double Emulsion and Evaporation Method: The emulsion and evaporation method which involves the addition of aqueous drug solutions into organic polymer solution under vigorous stirring to form w/o emulsions. Prepared w/o emulsion is then added into second aqueous phase with continuous stirring which form the w/o/w emulsion. This emulsion is subjected to solvent removal process by evaporation. Nanoparticles can be isolated by centrifugation at high speed. The prepared nanoparticles must be thoroughly washed and lyophilize.

3. Emulsions Diffusion Method: In this method encapsulating polymer is dissolved in a partially water miscible solvent and then these solvent is saturated with water. The polymer-water saturated solvent phase is emulsified in an aqueous solution which contain stabilizer, leading to solvent diffusion to the external phase and the formation of nanocapsules or nanospheres.

4. Solvent Displacement method: In this method precipitation of a polymer from organic solution and the diffusion of the organic solvent in the aqueous medium in the presence or absence of surfactant. Drug, Polymers, and/or lipophilic surfactant are dissolved in a water miscible semipolar solvent such as ethanol, acetone. The solution is then injected or poured into an aqueous solution under magnetic stirring. Nanoparticles prepared instantaneously by the rapid solvent diffusion. Then the solvent is removing from the suspension under reduced pressure.

5. Reverse Micelles: Reverse micelles are mixtures of water, oil and surfactant which are thermodynamically stable and shows a dynamic behaviour. The structure of reverse micelles consists of aqueous and oil volumes which are separated by surfactant films, as the observer zooms out to a more macroscopic scale reverse micelles appear homogeneous and isotropic. This advantage of reverse micellar formation is that ultrafine polymeric nanoparticles with narrow size distributions are produced, while applying traditional emulsion polymerization method larger nanoparticles (>200nm) will form with broad size distribution. The reverse micelle aqueous core acts as a Nano reactor in preparation of ultrafine nanoparticles.

6. Ionotropic Gelation: In this process in which polyelectrolyte is cross-linked with a counter ion which forms a hydrogel. The structures of hydrogels are maintained by hydrogen bonding, hydrophobic forces, ionic forces or molecular entanglements. For the preparation of micro and nanoparticles, this ionic gelation technique has been applied for encapsulation and controlled release of therapeutic agents by using a variety of materials including alginates, gellan gums, chitosan and carboxymethyl cellulose. Depending on the material used, the strength of the counter ion and the desired particle size several methods of Ionotropic gelation can be applied, including syringe dropping and air atomization for bead formation, and flush mixing for nanoparticles formation.

7. Incorporation of prepared nanoparticles into enteric coated capsule shell:

Enteric release capsules containing dried lyophilized nanoparticles of protein drug may be release nanoparticles in the intestine. The ligand conjugation may facilitate the permeation of nanoparticles across the intestinal wall. As the chitosan itself also acts as penetration enhancer³⁹ and ligand conjugation to chitosan also increase the penetration across the intestine.

DISCUSSION:

Different strategies have been studied in an effort to overcome challenges associated with delivery protein. The absolute oral bioavailability levels of most peptides and proteins are less than 1%. The challenge here is to improve the oral bioavailability from less than 1% to at least 30-50%⁴⁰.

The widely studied approaches can be generally categorized as chemical modifications and colloidal delivery systems⁴¹. Mateja Cegnar et.al. 2015 was found that erythropoietin (EPO) conjugates having a high bioavailability and efficacy, especially when administered perorally⁴². Lei Li et.al.2016 was formulated chitosan-based multifunctional nanocarriers modified by L-Valine target ligands and glucose-responsive units have been prepared for overcoming multiple barriers for oral delivery of insulin. The resultant nanocarriers exhibited relative lower cytotoxicity and excellent stability against protein solution. The obtained chitosan-based multifunctional nanocarriers exhibited excellent protective properties for insulin against enzymatic degradation⁴³. Jain A. et. al. 2015 was formulated L-Valine appended PLGA nanoparticles for oral insulin delivery which found that the small intestine has been shown to be able to transport the L-form of amino acid against concentration gradient. So, L-Valine was used as a ligand for carrier mediated transport of Insulin loaded polylactic-co-glycolic acid (PLGA) nanoparticles⁴⁴. Among chemical modifications, covalent conjugation of polymers such as PEG or polysialic acid to therapeutic proteins represents a relatively feasible and novel approach than the structural changes of proteins^45-46.

Bioavailability of Protein nanoparticles:

The effectiveness and safety of nanoparticles have been assessed for their bioavailability, physiological response, therapeutic effect, and cytotoxicity. Venkatesan et al. prepared liquid-filled nanoparticles by using solid adsorbents such as carbon nanohorns and carbon nanotubes⁴⁷. They found that liquid-filled protein carbon nanotubes improved the bioavailability of protein to 11.5% following invasive intra-small intestinal administration to rats. Bahgat E. Fayedet.al was loaded EPO in poly lactic-co glycolic acid (PLGA) nanoparticles which successfully altered the in vivo release profile and activity, allowing for more than 2-week activity after single injection using only double the EPO dose.^48-51 Thus due to entrapment of polypeptide drug in nanoparticles, the half-life of the drug may be increased and reduces the side-effects compared to conventional parenteral preparation. Thus the bioavailability of protein drug may improve with nanoparticulate technology.

CONCLUSION AND FUTURE PERSPECTIVE:

Polymeric nanoparticles protect drug from biological or chemical degradation and can able to provide prolonged drug release and augmenting drug efficacy and reduced side effect. Ligand conjugation enables to enhance permeability through intestinal epithelial cell by targeted delivery. Thus the controlled released formulation prepared by using polymeric nanoparticles having Low dose long-term therapy will give optimum therapeutic effect, so that the adverse effects related to high dose of parenteral administration are reduced and also convenient to patients.

By using such drug delivery system, there is a scope to formulate oral drug delivery system where protein drug can be protected by incorporating it into nanoparticles and colon targeting release the nanoparticles release at the intestinal site where penetration of drug across the intestine can be facilitate by using Ligand conjugation to polymer.

As the protein drug is very much sensitive to environmental factor thus it require very mild process, less chemical and thermal stability during preparation of its nanoparticles.

ACKNOWLEDGEMENTS:

We express my thanks to Kamla Nehru College of Pharmacy, Butibori, Nagpur for availing all the necessary facilities.

REFERENCES:

1. Vyas SP, Khar RK. Targeted and controlled drug delivery: novel carrier systems. CBS publishers and distributors; 2004.

2. Satyanarayan U, and Chakrapani. Biochemistry, 3rd Ed., Books and allied (p) Ltd., Kolkata,; U (2008)

3. Langer R, Folkman J. Polymers for the sustained release of proteins and other macromolecules. Nature. 1976; 263(5580): 797-800. doi: 10.1038/263797a0.

4. Al-Tahami K, Singh J. Smart polymer based delivery systems for peptides and proteins. Recent Pat Drug Deliv Formul. 2007; 1(1): 65-71. doi: 10.2174/187221107779814113.

5. Murdan S, van den Bergh B, Gregoriadis G, Florence AT. Water-in-sorbitan monostearate organogels (water-in-oil gels). J Pharm Sci. 1999; 88(6): 615-9. doi: 10.1021/js980343j.

6. Chein YW, Novel drug delivery systems 50, second edition, 715.

7. Sharma G, Sharma AR, Nam JS, Doss GP, Lee SS, Chakraborty C. Nanoparticle based insulin delivery system: the next generation efficient therapy for Type 1 diabetes. J Nanobiotechnology. 2015 Oct 24; 13: 74. doi: 10.1186/s12951-015-0136-y.

8. Dhapake PR, Avari JG. Application of polymeric nanoparticles in oral delivery of recombinant human erythropoietin: A review. Journal of Drug Delivery and Therapeutics. 2019; 9(1-s): 403-7. DOI:10.22270/jddt.v9i1-s.2336

9. Lagassé HA, Alexaki A, Simhadri VL, Katagiri NH, Jankowski W, Sauna ZE, Kimchi-Sarfaty C. Recent advances in (therapeutic protein) drug development. F1000Res. 2017 Feb 7; 6: 113. doi: 10.12688/f1000research.9970.1.

10. Herrero EP, Alonso MJ, Csaba N. Polymer-based oral peptide nanomedicines. Ther Deliv. 2012; 3(5): 657-68. doi: 10.4155/tde.12.40.

11. Damgé C, Maincent P, Ubrich N. Oral delivery of insulin associated to polymeric nanoparticles in diabetic rats. J Control Release. 2007; 117(2): 163-70. doi: 10.1016/ j.jconrel.2006.10.023.

12. Kurian G, Seetharaman A, Subramanian N, Paddikkala J. A Novel Approach for Oral Delivery of Insulin via Desmodium gangeticum Aqueous Root Extract. J Young Pharm. 2010; 2(2): 156-61. doi: 10.4103/0975-1483.63158.

13. Woitiski CB, Carvalho RA, Ribeiro AJ, Neufeld RJ, Veiga F. Strategies toward the improved oral delivery of insulin nanoparticles via gastrointestinal uptake and translocation. BioDrugs. 2008; 22(4): 223-37. doi: 10.2165/00063030-200822040-00002.

14. Savale SK. Protein and peptide drug delivery system. World J Pharm Pharm Sci. 2016; 5(4): 1-9.10.20959/wjpps20164-6425

15. Patel J, Chauhan S, Seth A. Formulation and Evaluation of Methotrexate Loaded Nanoparticle. International Journal of Drug Discovery and Medical Research. 2012; 2:1: 56-60

16. Sharma, G., Sharma, A.R., Nam, JS. et al. Nanoparticle based insulin delivery system: the next generation efficient therapy for Type 1 diabetes. J Nanobiotechnol 13, 74 (2015). doi.org/10.1186/ s12951-015-0136-y

17. Varma MV, Ashokraj Y, Dey CS, Panchagnula R. P-glycoprotein inhibitors and their screening: a perspective from bioavailability enhancement. Pharmacol Res. 2003; 48(4): 347-59. doi: 10.1016/ s1043-6618(03)00158-0.

18. Kumari A, Yadav SK, Yadav SC. Biodegradable polymeric nanoparticles based drug delivery systems. Colloids Surf B Biointerfaces. 2010; 75(1): 1-18. doi: 10.1016/ j.colsurfb.2009.09.001.

19. Chakraborty C, Pal S, Doss GP, Wen ZH, Lin CS. Nanoparticles as' smart'pharmaceutical delivery. Frontiers in bioscience (Landmark edition). 2013; 18: 1030-50. doi.org/10.2741/4161

20. des Rieux A, Fievez V, Garinot M, Schneider YJ, Préat V. Nanoparticles as potential oral delivery systems of proteins and vaccines: a mechanistic approach. Journal of controlled release. 2006; 116(1): 1-27. DOI: 10.1016/j.jconrel.2006.08.013

21. Singh R, Lillard JW Jr. Nanoparticle-based targeted drug delivery. Exp Mol Pathol. 2009; 86(3): 215-23. doi: 10.1016/ j.yexmp.2008.12.004.

22. Kavimandan NJ, Losi E, Peppas NA. Novel delivery system based on complexation hydrogels as delivery vehicles for insulin-transferrin conjugates. Biomaterials. 2006; 27(20): 3846-54. doi: 10.1016/j.biomaterials.2006.02.026.

23. Roger E, Lagarce F, Garcion E, Benoit JP. Biopharmaceutical parameters to consider in order to alter the fate of nanocarriers after oral delivery. Nanomedicine (Lond). 2010; 5(2): 287-306. doi: 10.2217/nnm.09.110.

24. Vandamme K, Melkebeek V, Cox E, Deforce D, Lenoir J, Adriaens E, Vervaet C, Remon JP. Influence of reaction medium during synthesis of Gantrez AN 119 nanoparticles for oral vaccination. Eur J Pharm Biopharm. 2010; 74(2): 202-8. doi: 10.1016/j.ejpb.2009.10.001.

25. Lochner N, Pittner F, Wirth M, Gabor F. Wheat germ agglutinin binds to the epidermal growth factor receptor of artificial Caco-2 membranes as detected by silver nanoparticle enhanced fluorescence. Pharm Res. 2003; 20(5): 833-9. doi: 10.1023/ a:1023406224028.

26. Chalasani KB, Russell-Jones GJ, Jain AK, Diwan PV, Jain SK. Effective oral delivery of insulin in animal models using vitamin B12-coated dextran nanoparticles. J Control Release. 2007; 122(2): 141-50. doi: 10.1016/j.jconrel.2007.05.019.

27. Farokhzad OC, Langer R. Impact of nanotechnology on drug delivery. ACS Nano. 2009; 3(1): 16-20. doi: 10.1021/nn900002m.

28. Dange YD, Honmane SM, Patil PA, Gaikwad UT, Jadge DR. Nanotechnology, Nanodevice Drug Delivery System: A Review. Asian J. Pharm. Tech. 2017; 7(2): 63-71. doi: 10.5958/2231-5713.2017.00010.1

29. Jung T, Kamm W, Breitenbach A, Kaiserling E, Xiao JX, Kissel T. Biodegradable nanoparticles for oral delivery of peptides: is there a role for polymers to affect mucosal uptake? Eur J Pharm Biopharm. 2000; 50(1): 147-60. doi: 10.1016/s0939-6411(00)00084-9.

30. Woitiski CB, Carvalho RA, Ribeiro AJ, Neufeld RJ, Veiga F. Strategies toward the improved oral delivery of insulin nanoparticles via gastrointestinal uptake and translocation. BioDrugs. 2008; 22(4): 223-37. doi: 10.2165/00063030-200822040-00002.

31. Chen MC, Mi FL, Liao ZX, Hsiao CW, Sonaje K, Chung MF, Hsu LW, Sung HW. Recent advances in chitosan-based nanoparticles for oral delivery of macromolecules. Adv Drug Deliv Rev. 2013; 65(6): 865-79. doi: 10.1016/j.addr.2012.10.010.

32. Sonaje K, Chen YJ, Chen HL, Wey SP, Juang JH, Nguyen HN, Hsu CW, Lin KJ, Sung HW. Enteric-coated capsules filled with freeze-dried chitosan/poly(gamma-glutamic acid) nanoparticles for oral insulin delivery. Biomaterials. 2010; 31(12): 3384-94. doi: 10.1016/j.biomaterials.2010.01.042.

33. Su FY, Lin KJ, Sonaje K, Wey SP, Yen TC, Ho YC, Panda N, Chuang EY, Maiti B, Sung HW. Protease inhibition and absorption enhancement by functional nanoparticles for effective oral insulin delivery. Biomaterials. 2012; 33(9): 2801-11. doi: 10.1016/j.biomaterials.2011.12.038.

34. Radwan MA, Aboul-Enein HY. The effect of absorption enhancers on the initial degradation kinetics of insulin by alpha-chymotrypsin. Int J Pharm. 2001; 217(1-2): 111-20. doi: 10.1016/s0378-5173(01)00595-6.

35. Su FY, Lin KJ, Sonaje K, Wey SP, Yen TC, Ho YC, Panda N, Chuang EY, Maiti B, Sung HW. Protease inhibition and absorption enhancement by functional nanoparticles for effective oral insulin delivery. Biomaterials. 2012; 33(9): 2801-11. doi: 10.1016/j.biomaterials.2011.12.038.

36. Park K, Kwon IC, Park K. Oral protein delivery: Current status and future prospect. Reactive and Functional Polymers. 2011; 71(3): 280-287. doi: 10.1016/j.reactfunctpolym.2010.10.002

37. Jain A, Jain SK. L-Valine appended PLGA nanoparticles for oral insulin delivery. Acta Diabetol. 2015; 52(4): 663-76. doi: 10.1007/s00592-015-0714-3.

38. https://www.google.com/patents/WO2015032981A1?cl=en&utm_source=gb-gplus-sharePatent WO2015032981A1 - Erythropoietin conjugates having oral bioavailability

39. Sadeghi AM, Dorkoosh FA, Avadi MR, Weinhold M, Bayat A, Delie F, Gurny R, Larijani B, Rafiee-Tehrani M, Junginger HE. Permeation enhancer effect of chitosan and chitosan derivatives: comparison of formulations as soluble polymers and nanoparticulate systems on insulin absorption in Caco-2 cells. Eur J Pharm Biopharm. 2008; 70(1): 270-8. doi: 10.1016/ j.ejpb.2008.03.004.

40. Saffran M, Kumar GS, Savariar C, Burnham JC, Williams F, Neckers DC. A new approach to the oral administration of insulin and other peptide drugs. Science. 1986; 233(4768): 1081-4. doi: 10.1126/science.3526553.

41. Nagarajana E, Shanmugasundarama P, Ravichandirana V, Vijayalakshmia A, Senthilnathanb B, Masilamanib K. Development and evaluation of chitosan based polymeric nanoparticles of an antiulcer drug lansoprazole. Journal of Applied Pharmaceutical Science. 2015; 5(4): 020-5.

42. Yang X, Patel A, Vadlapudi AD, Mitra AK. Application of nanotechnology in ocular drug delivery. Bentham Science Publishers, Sharjah, United Arab Emirates; 2013 Jun 26.Mateja C, Barbara P, Porekar V, Gaberc S, Mateja N, Spela J, Radovan K, Simon C, Erythropoietin conjugates having oral bioavailability. https//www.google.com/patent/ 2015;032981? cl= en&utm_source=gb-gplus-sharePatent WO2015032981A1.

43. Li L, Jiang G, Yu W, Liu D, Chen H, Liu Y, Tong Z, Kong X, Yao J. Preparation of chitosan-based multifunctional nanocarriers overcoming multiple barriers for oral delivery of insulin. Materials science and engineering: C. 2017; 70: 278-86.

44. Jain A, Jain SK. L-Valine appended PLGA nanoparticles for oral insulin delivery. Acta diabetologica. 2015; 52(4): 663-76.

45. Irfan M. Saiyyad, D. S. Bhambere, Sanjay Kshirsagar. Formulation and Optimization of Silymarin Loaded PLGA Nanoparticle for liver targeting. Asian J. Pharm. Tech. 2017; 7(4): 209-220. doi: 10.5958/2231-5713.2017.00032.0

46. Pradnya M. Khandagale, Manish M. Rokade, Prof. Dipti G. Phadtare. Controlled Drug Delivery System-A Novel Approach. Asian J. Pharm. Tech. 2018; 8 (3): 161-164.

47. Venkatesan N, Yoshimitsu J, Ito Y, Shibata N, Takada K. Liquid filled nanoparticles as a drug delivery tool for protein therapeutics. Biomaterials. 2005; 26(34): 7154-63. doi: 10.1016/ j.biomaterials.2005.05.012.

48. Fayed BE, Tawfik AF, Yassin AE. Novel erythropoietin-loaded nanoparticles with prolonged in vivo response. J Microencapsul. 2012; 29(7): 650-6. doi: 10.3109/02652048.2012.680507.

49. Ray A. Liposome in Drug delivery system. Asian Journal of Research in Pharmaceutical Science. 2012; 2(2): 41-4.

50. Magdum SV, Patil SV, Patil SS. Magnetic Nanoparticles for Cancer Therapy. Asian Journal of Pharmacy and Technology. 2017; 7(4): 251-60. doi:10.5958/2231-5713.2017.00037.X

51. G. Sivasankari, S. Boobalan, D. Deepa. Dopamine sensor by Gold Nanoparticles Absorbed Redox behaving metal Complex. Asian J. Pharm. Tech. 2018; 8(2): 83-87. doi:10.5958/2231-5713.2018.00013.2

Received on 15.11.2022 Modified on 31.01.2023

Asian J. Res. Pharm. Sci. 2023; 13(2):139-144.

DOI: 10.52711/2231-5659.2023.00025