Pharmaceutical Spoilage Overview

Spoilage of Pharmaceutical Products

• Deterioration of physical, chemical, or biological properties rendering products unusable.
• Caused by microbial contamination, chemical degradation, or physical damage.

Microbial Spoilage

• Most common type, caused by microorganism growth.
• Microorganisms produce toxins, enzymes, and metabolites that degrade active ingredients, alter appearance, and create off-odors and flavors.
• Sources include the environment, raw materials, personnel, and equipment.

Non-Microbial Spoilage

• Chemical spoilage is caused by chemical reactions, such as oxidation, hydrolysis, and photolysis.
• Physical spoilage results from physical damage like breakage, cracking, or crushing.
• Enzymatic spoilage occurs due to enzymes like lipase, protease, or maltase, leading to hydrolysis of liquids.

Factors Affecting Microbial Spoilage

• Nutritional factors: Microorganisms need carbon, nitrogen, phosphorus, sulfur, and vitamins; presence of these nutrients increases spoilage risk.
• Water: Water is essential for microbial growth; higher water activity (aw) in products increases susceptibility to spoilage.
• Storage temperature: Optimal temperature for growth varies, but most microbes thrive between 4°C and 60°C.
• pH: Most microbes prefer neutral or slightly acidic conditions, but some tolerate extreme pH values.
• Redox potential: Aerobic microorganisms prefer high redox potential, while anaerobic organisms favor low redox potential.
• Package design: Packaging should prevent microbial ingress and maintain sterility.

Sources and Types of Microbial Contamination

• Atmosphere: Microorganisms are carried in dust, skin, clothing, moisture, or through coughing/sneezing. Common isolates include bacteria and fungi.
• People: The most common source, with microbes found on skin, hair, clothing, and respiratory tracts.
• Raw Materials: Contaminated water, excipients, and active ingredients can introduce microbes.
• Equipment: Improperly cleaned equipment can harbor microorganisms.

Preservatives

• Used to prevent microbial spoilage in pharmaceutical products.
• Examples include methyl paraben, phenol, benzyl alcohol, thiomersal, bronopol, and alcohol.
• Concentration depends on the formulation and the preservative used.

Preservative Characteristics

• Rapidly kill all microbial contaminants.
• Non-toxic.
• Non-irritant.
• Cost-effective.
• Physically and chemically stable.

Evaluation of Microbial Stability

• Depends on the preservative's effectiveness.
• Chemical and biological assays may ensure effectiveness, but activity can be lost due to other formulation ingredients.
• Some formulations act as self-preservatives or contain antimicrobial agents.
• Microbial stability testing ensures the formulation can resist microbial growth.
• Inoculated products with specific microorganisms are tested at different intervals to determine viable count.

Animal Cell Culture

• In-vitro cultivation of animal cells in a controlled environment with necessary nutrients.

General Procedure for Cell Culture

• Designing animal cell culture media is more complex than for microorganisms or plants.
• Media selection depends on cell type and culture objective.

Culture Media Types

• Natural: Derived from natural sources like plasma clot, biological fluids, and tissue extracts.
• Artificial: Prepared with organic and inorganic nutrients, vitamins, salts, serum protein, carbohydrates, and gases.

Procedure for Cell Culture

1. Isolation of tissue: Explant from an animal is surgically removed and surface-sterilized.
2. Disaggregation of tissue: Primary cell culture obtained by disaggregating tissue mechanically, enzymatically, or with chelating agents.
3. Seeding: Dissociated cells are seeded in culture vessels.

Stages of Cell Culture

• Primary cell culture: Cells are isolated from an organ and grown in vitro.
• Established cell culture: Primary cells are subcultured for 70-80 times, resulting in faster growth.
• Transformed cell culture: Established cell lines become immortal due to genetic transformation, resulting in indefinite growth.

Applications of Cell Cultures in Pharmaceutical Industry

• Drug discovery and development: Screening for efficacy and toxicity.
• Mechanism of action studies.
• Biomarker identification to predict patient response.