Biopharmaceutics & Pharmacokinetics Complete Revision Notes | Introduction, Drug Transport Mechanism, Biological Membrane, Passive Diffusion, Facilitated Diffusion, Active Transport, Filtration, Osmosis, Carrier Mediated Transport, Symport, Antiport, Endocytosis, Exocytosis, Bioavailability, First Pass Metabolism, Factors Affecting Drug Absorption
🌟 Biopharmaceutics & Pharmacokinetics Complete Revision Notes | Introduction, Drug Transport Mechanism, Biological Membrane, Passive Diffusion, Facilitated Diffusion, Active Transport, Filtration, Osmosis, Carrier Mediated Transport, Symport, Antiport, Endocytosis, Exocytosis, Bioavailability, First Pass Metabolism, Factors Affecting Drug Absorption & Exam Important Points
🔷 🌟 Biopharmaceutics & Pharmacokinetics Complete Revision Notes | Introduction, Drug Transport Mechanism, Biological Membrane, Passive Diffusion, Facilitated Diffusion, Active Transport, Filtration, Osmosis, Carrier Mediated Transport, Symport, Antiport, Endocytosis, Exocytosis, Bioavailability, First Pass Metabolism, Factors Affecting Drug Absorption & Exam Important Points
🔷 Introduction to Biopharmaceutics
📘 Definition
Biopharmaceutics pharmaceutical science की branch है जो study करती है:
🔹 Drug dosage form
🔹 Drug release
🔹 Drug absorption
🔹 Bioavailability
💡 Important Point
यह बताती है कि dosage form drug के absorption और therapeutic effect को कैसे affect करता है।
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🟢 Introduction to Pharmacokinetics
📘 Definition
Pharmacokinetics का meaning है:
“What the body does to the drug.”
💡 Important Point
इसमें body drug के साथ क्या करती है यह study होता है।
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🟡 Main Processes of Pharmacokinetics (ADME)
🧪 A = Absorption
Drug bloodstream में enter करती है।
🚚 D = Distribution
Drug blood से tissues तक जाती है।
⚙️ M = Metabolism
Drug body में breakdown होती है।
🚽 E = Excretion
Drug body से remove होती है।
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🔴 Absorption
📘 Definition
Drug का site of administration से bloodstream में जाना absorption कहलाता है।
🟣 Distribution
📘 Definition
Blood से drug का body tissues में जाना distribution कहलाता है।
🔵 Metabolism
📘 Definition
Drug का body में chemical conversion metabolism कहलाता है।
💡 Important Point
Mainly liver में होता है।
🟠 Excretion
📘 Definition
Drug का body से removal excretion कहलाता है।
💡 Important Point
Mainly kidney से होता है।
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🌟 What is Drug Transport?
📘 Definition
Drug का biological membrane के across movement drug transport कहलाता है।
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🔷 Importance of Drug Transport
⭐ Drug absorption transport पर depend करता है।
⭐ Drug onset of action transport से affect होता है।
⭐ Drug bioavailability transport mechanism पर depend करती है।
⭐ Drug toxicity और therapeutic effect भी transport पर depend करते हैं।
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🟢 Biological Membrane
📘 Structure of Biological Membrane
Biological membrane mainly बनी होती है:
🟡 Phospholipid bilayer
🟡 Proteins
🟡 Cholesterol
🟡 Carbohydrates
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🔵 Fluid Mosaic Model
📘 Definition
Membrane dynamic होती है।
💡 Important Point
Lipids और proteins continuously move करते रहते हैं।
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🟣 Functions of Biological Membrane
🛡️ Selective permeability
🚚 Transport of substances
📡 Cell communication
🔒 Protection
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🔴 Types of Drug Transport Mechanism
🔹 Passive Transport
🔹 Active Transport
🔹 Vesicular Transport
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🟢 Passive Transport
📘 Definition
Drug:
High concentration → Low concentration
move करती है without energy।
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🔷 Characteristics of Passive Transport
⚡ ATP required नहीं होता
🚫 Carrier required नहीं होता
🧪 Simple process होता है
🌟 Most common transport mechanism है
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🔵 Types of Passive Transport
🔹 Passive Diffusion
🔹 Facilitated Diffusion
🔹 Filtration
🔹 Osmosis
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🟣 Passive Diffusion
📘 Definition
Drug membrane के lipid layer के through diffuse करती है।
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🔴 Characteristics of Passive Diffusion
⭐ Most common absorption mechanism
🧈 Lipid soluble drugs easily absorb होती हैं
⚡ Unionized drugs rapidly absorb होती हैं
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🟢 Why Lipid Soluble Drugs Absorb Faster?
📘 Reason
Biological membrane lipid nature की होती है।
💡 Important Point
“Like dissolves like” principle follow होता है।
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🔷 Factors Affecting Passive Diffusion
🧈 Lipid Solubility
More lipid soluble = Faster absorption
🧬 Molecular Size
Small size = Faster diffusion
🌍 Surface Area
Large area = More absorption
📏 Membrane Thickness
Thin membrane = Faster transport
📈 Concentration Gradient
High gradient = Faster movement
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🔵 Fick’s Law of Diffusion
📘 Formula
Rate of diffusion = (D × K × A × (C1 − C2)) / h
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🟣 Meaning of Terms
🔹 D = Diffusion coefficient
🔹 K = Partition coefficient
🔹 A = Surface area
🔹 h = Membrane thickness
🔹 C1 − C2 = Concentration gradient
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🔴 pH Partition Theory
💡 Important Rule
Unionized drugs absorb better than ionized drugs।
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🟢 Weak Acid Absorption
💊 Example = Aspirin
📍 Absorbed in stomach
📘 Reason
Stomach acidic होता है।
Aspirin unionized form में होती है।
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🔵 Weak Base Absorption
💊 Example = Morphine
📍 Absorbed in intestine
📘 Reason
Intestine alkaline होता है।
Weak base unionized form में convert होती है।
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🟡 Henderson Hasselbalch Equation
🧪 Formula for Weak Acid
pH = pKa + log (Salt / Acid)
🧪 Formula for Weak Base
pH = pKa + log (Base / Salt)
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🟣 Facilitated Diffusion
📘 Definition
Drug carrier protein की help से transport होती है without ATP।
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🔴 Characteristics of Facilitated Diffusion
🚚 Carrier required
⚡ ATP required नहीं
🎯 Specific transport
📈 Saturable process
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🟢 Example of Facilitated Diffusion
🍬 Glucose transport by GLUT transporter
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🔵 Filtration
📘 Definition
Drug pores के through pressure की help से move करती है।
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🟣 Characteristics of Filtration
💧 Water soluble drugs pass करती हैं
🧬 Small molecules transport होते हैं
📈 Hydrostatic pressure important होता है
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🟢 Examples of Filtration
💧 Urea
💧 Water
⚡ Electrolytes
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🔴 Osmosis
📘 Definition
Water low solute concentration से high solute concentration की तरफ move करता है।
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🟡 Importance of Osmosis
💧 Water absorption
🩺 Kidney function
🧫 Cell volume maintenance
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🟢 Active Transport
📘 Definition
Drug:
Low concentration → High concentration
move करती है using ATP।
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🔷 Characteristics of Active Transport
⚡ ATP required
🚚 Carrier required
📈 Saturable process
🎯 Selective transport
⚔️ Competitive inhibition होता है
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🔵 Why Active Transport Needed?
📘 Reason
Body को concentration gradient के against transport करना पड़ता है।
💡 Important Point
इसलिए ATP energy required होती है।
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🟣 Types of Active Transport
🔹 Primary Active Transport
🔹 Secondary Active Transport
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🔴 Primary Active Transport
📘 Definition
Direct ATP use होता है।
💊 Example
Na+/K+ ATPase Pump
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🟢 Function of Na+/K+ Pump
⬆️ 3 Na+ outside
⬇️ 2 K+ inside
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🔵 Importance of Na+/K+ Pump
🧠 Nerve conduction
💪 Muscle contraction
⚡ Membrane potential maintenance
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🟡 Secondary Active Transport
📘 Definition
Indirect ATP use होता है।
💡 Important Point
Na+ gradient की energy use होती है।
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🟣 Carrier Mediated Transport
📘 Types
🔹 Uniport
🔹 Symport
🔹 Antiport
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🔴 Uniport
📘 Definition
Single substance transport
💊 Example
GLUT transporter
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🟢 Symport (Co-transport)
📘 Definition
Two substances same direction में move करती हैं।
💊 Example
Na+/Glucose transporter
📘 Reason
Na+ glucose को pull करता है।
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🔵 Antiport (Counter Transport)
📘 Definition
Two substances opposite direction में move करती हैं।
💊 Example
Na+/Ca2+ exchanger
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🟡 Vesicular Transport
📘 Definition
Large molecules vesicle की help से transport होती हैं।
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🔴 Types of Vesicular Transport
🔹 Endocytosis
🔹 Exocytosis
🔹 Transcytosis
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🟢 Endocytosis
📘 Definition
Substance cell के अंदर जाता है।
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🔷 Types of Endocytosis
🍽️ Phagocytosis
🥤 Pinocytosis
🎯 Receptor Mediated Endocytosis
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🔵 Phagocytosis
📘 Meaning
Cell Eating
💊 Example
Macrophage bacteria engulf करता है।
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🟣 Pinocytosis
📘 Meaning
Cell Drinking
💊 Example
Fluid uptake by cells
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🔴 Receptor Mediated Endocytosis
📘 Definition
Specific receptor की help से uptake होता है।
💊 Example
Vitamin B12 absorption
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🟢 Exocytosis
📘 Definition
Cell substances बाहर release करता है।
💊 Example
Hormone secretion
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🔵 Transcytosis
📘 Definition
One side से entry और दूसरी side से exit होता है।
💊 Example
Antibody transport
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🔴 P-glycoprotein (P-gp)
📘 Definition
Drug को cell से बाहर pump करता है।
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🟢 Importance of P-glycoprotein
⚠️ Drug resistance cause करता है
📉 Drug absorption को decrease करता है
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🔵 Examples
💊 Digoxin
💊 Anticancer drugs
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🟣 Factors Affecting Drug Absorption
🧈 Lipid solubility
🩸 Blood flow
🌍 Surface area
🧪 pH
🍔 Food
⚕️ Disease condition
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🟡 Bioavailability
📘 Definition
Fraction of administered drug reaching systemic circulation।
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🔴 Formula of Bioavailability
🧪 F = (AUC oral / AUC IV) × 100
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🟢 First Pass Metabolism
📘 Definition
Liver drug को metabolize कर देता है before systemic circulation।
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🔵 Examples of First Pass Metabolism
💊 Nitroglycerin
💊 Propranolol
💊 Lidocaine
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🔷 One Line Quick Revision
⚡ Passive diffusion = No ATP
🚚 Facilitated diffusion = Carrier but no ATP
🔋 Active transport = Carrier + ATP
➡️ Symport = Same direction transport
↔️ Antiport = Opposite direction transport
🍽️ Phagocytosis = Cell eating
🥤 Pinocytosis = Cell drinking
⬇️ Endocytosis = Into cell
⬆️ Exocytosis = Out of cell
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