Chitosan Nanoparticles - Challenges for Antibiotic Drug Delivery using Penicillin as a Model Drug 5th International Conference and Exhibition on Pharmaceutics & Novel Drug Delivery Systems March 16-18, 2015 Crowne Plaza, Dubai, UAE Dr. B. B.Barik Professor, Dept. of Pharmaceutics Mohammed M. Safhi, S.M.Sivakumar, Aamena Jabeen, Foziyah Zakir & Farah Islam College of Pharmacy, Jazan University,  Kingdom of Saudi Arabia. E-mail: bbbarik2003@gmail.com

INTRODUCTION Antibiotic resistance is one of the major health and economic problems worldwide eroding the discovery of antibiotics and their application to clinical medicine. It has been estimated that each year in US, approximately 2 million people get infected with antibiotic resistance bacteria and 23,000 die as a result of these infections . Resistance to penicillin is well recognized in Staphylococcus aureus and Staphylococcus epidermidis . Use of nanoparticles for antibiotic delivery is increasing due to increased prevalence of antibiotic resistant bacterial strains.

Antibiotic Resistance

WHY NANOPARTICLES AND WHY CHITOSAN? Nanoparticles can easily bypass efflux mechanism, particularly chitosan nanopartilcles because chitosan is highly poly cationic can easily bind with anionic microbial cells. Efflux mechanism: Membrane proteins that export antibiotics from the cell and maintain their low intracellular concentrations. Outer membrane permeability: An asymmetric bilayer: the phospholipid form the inner leaflet and the lipopolysaccharides (LPS) form the outer leaflet, provides a formidable barrier that must be overcome by drugs.

Objective The objective of this study was to formulate and characterize chitosan nanoparticles of penicillin G to improve the bioavailability and prevent drug resistance.

Method Ionic gelation technique was used to encapsulate penicillin G in chitosan nanoparticles. The anti bacterial efficacy of penicillin-loaded chitosan nanoparticles were evaluated against five bacterial strains namely: Staphylococcus aureus Streptococcus pyogenes Bacillus subtilis Escherichia coli and Klebsiella planticola The antibacterial effect of penicillin nanoparticles was compared with conventional penicillin drug.

Preparation of chitosan nanoparticle of penicillin G 1% w/v chitosan solution was prepared with 1% v/v glacial acetic acid having pH 4. The pH was increased to 6 by adding 1ml of 1N NaOH. The chitosan gel was homogenized at 3600 rpm for 30 minutes During homogenization 1 ml of 1% w/v of penicillin G was added. Sonication was done for 30 seconds at pre determined time interval. 500 μl of formaldehyde was added drop by drop and homogenization was continued for one hour. The penicillin loaded nanoparticles were washed & dried.

Prepartion of pencillin – chitosan nanoparticles IONIC GELLATION TECHNIQUE

Chitosan Chitosan cross linking

Characterisation of nanoparticles Morphology The nanoparticles were observed under TEM with an accelerating voltage of 100 kv Zeta potential, Particle size and PDI The zeta potential, size and PDI of penicillin loaded chitosan nanoparticles were measured by using Nano – ZS zeta sizer, Malvern Instruments, UK. In vitro release profile 2 ml of penicillin loaded chitosan nanoparticles were taken in 50 ml of phosphate buffer of pH 6.0 placed in a beaker and stirred in a magnetic stirrer at 50 rpm for 48 hrs at a temperature of 25ºC. The samples were withdrawn, centrifused and assayed spectrophotometrically at 208 nm.

Assessment of antibacterial activity Following five bacterial strains were used: Staphylococcus aureus, Streptococcus pyogenes, Bacillus subtilis, Escheriachia coli and Klebsiella planticola The MIC was determined in Nutrient Broth using two-fold serial dilutions of chitosan nanoparticles with initial bacterial inoculums of 10-6 CFU and the time and temperature of incubation being 24 hours and 370C, respectively.

Morphology and Size TEM analysis

Zeta potential, Particle size and pdi: Polymer Cross linker Before sonication After sonication Size (nm) PdI Zeta potntial Sonication time (Sec) 0.1% 250 µl 644.2 1.00 35.4 mV 10 497.2 0.59 55.4 500 µl 585.9 0.63 42.4 15 401.1 0.48 62.8 1000 µl 1057 0.7 37.3 20 3 0.3 52.3 1500 µl 1167 0.8 33.7 25 661 0.51 46.8

In vitro release

Anti bacterial studies

CONCLUSION This work confirms that ionic gelation technique is a successful method to encapsulate penicillin in chitosan nanoparticles. Penicillin is released in sustained manner from chitosan nanoparticle. It showed better microbial action than conventional penicillin.

References CDC.Active Bacterial Core Surveillance Methodology (2012).http://www.cdc.gov/abcs/ index.html Kimberlin, C., Khalid, F., Hariri, A. Resistance of staphylococci to penicillin-G and cloxacillin. Pahlavi Med J. 9(2),1978, 182 - 192. Guo, L., Yang, S. Synthesis and Characterization of Poly(vinylpyrrolidone)-Modified Zinc Oxide nanoparticles. Chem. Mater. 12, 2000, 2268-2274 Pertha, S., Amit, K.G., Goutam, R. Formulation and evaluation of chitosan based ampicillin trihydrate nanoparticles. Trop J Pharm Res. 9(5), 2010 : 483 – 488. Sarmento, B., Riberio A, Veiga F, Sampaio P, Neufeld R, Ferreira D. Alginate/Chitosan nanoparticles are effective for oral insulin delivery. Pharmaceutical Research. 2007; 24(12): 2198 – 2206

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