Atropine – industrial production and use is a concise guide for B.Pharm students covering the tropane alkaloid atropine, its botanical sources (Atropa belladonna, Datura), chemical nature (tropane alkaloid, racemic hyoscyamine), and routes of supply including plant extraction and synthetic/semi‑synthetic methods (Robinson tropinone route, esterification with tropic acid). This introduction highlights industrial purification, conversion to atropine sulfate, analytical methods (HPLC, TLC, Dragendorff test), quality control, stability, formulation, therapeutic uses (antimuscarinic, bradycardia, organophosphate poisoning, ophthalmic), and safety considerations. Emphasis is on production parameters, regulatory monographs, and practical QC testing. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. What is the primary natural botanical source commonly used for commercial extraction of atropine?
- Digitalis purpurea
- Atropa belladonna
- Papaver somniferum
- Cinchona officinalis
Correct Answer: Atropa belladonna
Q2. To which chemical class does atropine belong?
- Isoquinoline alkaloid
- Tropane alkaloid
- Quinoline alkaloid
- Indole alkaloid
Correct Answer: Tropane alkaloid
Q3. Atropine is best described as which of the following stereochemical forms?
- Pure levo-hyoscyamine enantiomer
- Pure dextro-hyoscyamine enantiomer
- Racemic mixture of hyoscyamine enantiomers
- Achiral aglycone of hyoscyamine
Correct Answer: Racemic mixture of hyoscyamine enantiomers
Q4. What is a common industrial method for extracting atropine from plant material?
- Supercritical CO2 extraction without pH adjustment
- Acidified aqueous extraction followed by basification and organic solvent extraction
- Direct crystallization from powdered plant at neutral pH
- Steam distillation of fresh leaves
Correct Answer: Acidified aqueous extraction followed by basification and organic solvent extraction
Q5. Which salt form of atropine is most commonly manufactured for injections and standard formulations?
- Atropine nitrate
- Atropine acetate
- Atropine sulfate
- Atropine hydrochloride
Correct Answer: Atropine sulfate
Q6. Which synthetic precursor and classic route is associated with industrial tropane alkaloid synthesis?
- Robinson tropinone synthesis followed by esterification with tropic acid
- Fischer indole synthesis followed by methylation
- Pictet–Spengler condensation with tryptamine
- Hantzsch dihydropyridine synthesis then oxidation
Correct Answer: Robinson tropinone synthesis followed by esterification with tropic acid
Q7. In quality control, which chromatographic method is most commonly used for quantitative assay of atropine in formulations?
- Gas chromatography with flame ionization detector
- Thin-layer chromatography without densitometry
- High-performance liquid chromatography with UV detection
- Paper chromatography
Correct Answer: High-performance liquid chromatography with UV detection
Q8. Which reagent gives a characteristic orange or reddish precipitate with atropine in qualitative alkaloid testing?
- Benedict’s reagent
- Dragendorff’s reagent
- Ferric chloride solution
- Biuret reagent
Correct Answer: Dragendorff’s reagent
Q9. During industrial conversion to the sulfate salt, what is the typical chemical step applied to the atropine free base?
- Treatment with acetic anhydride
- Neutralization with sodium hydroxide
- Reaction with sulfuric acid and crystallization
- Oxidation with potassium permanganate
Correct Answer: Reaction with sulfuric acid and crystallization
Q10. Which pharmacological action best describes atropine?
- Nicotinic receptor agonist
- Muscarinic receptor antagonist (antimuscarinic)
- Beta-adrenergic agonist
- Acetylcholinesterase inhibitor
Correct Answer: Muscarinic receptor antagonist (antimuscarinic)
Q11. Which therapeutic use is NOT an accepted clinical application of atropine?
- Treatment of symptomatic bradycardia
- Preanesthetic to reduce salivation
- Treatment of acute organophosphate poisoning as first-line alone
- Mydriasis and cycloplegia in ophthalmology
Correct Answer: Treatment of acute organophosphate poisoning as first-line alone
Q12. What is the approximate pKa of the tertiary amine in atropine, relevant to extraction and salt formation?
- pKa ≈ 4.5
- pKa ≈ 7.0
- pKa ≈ 9.7
- pKa ≈ 12.5
Correct Answer: pKa ≈ 9.7
Q13. Which storage condition is most appropriate for commercial atropine sulfate powder to minimize degradation?
- Exposed to light at room temperature
- Open container at high humidity
- Sealed, protected from light, in a cool dry place
- Frozen at −20°C in direct sunlight
Correct Answer: Sealed, protected from light, in a cool dry place
Q14. Which adverse effect is most characteristic of atropine overdose?
- Bradycardia and hypersalivation
- Excessive lacrimation and bronchorrhea
- Dry mouth, flushed skin, hyperthermia, delirium
- Profuse sweating and pinpoint pupils
Correct Answer: Dry mouth, flushed skin, hyperthermia, delirium
Q15. In an industrial extraction process, why is the plant extract first acidified before extraction?
- To convert atropine to its nonpolar free base for organic extraction
- To enhance hydrolysis of atropine into inactive components
- To convert atropine into its water-soluble salt form for aqueous partitioning
- To precipitate atropine as an insoluble sulfate
Correct Answer: To convert atropine into its water-soluble salt form for aqueous partitioning
Q16. Which pharmacopeial tests are typically required for released batches of atropine sulfate injection? (Select the best single answer)
- Only visual inspection and pH
- Assay (potency), sterility, bacterial endotoxins, and identity
- Melting point and ash content only
- Organoleptic tests and osmolality only
Correct Answer: Assay (potency), sterility, bacterial endotoxins, and identity
Q17. Which impurity is most relevant to monitor in atropine preparations due to biosynthetic related alkaloids?
- Scopolamine (hyoscine)
- Caffeine
- Nicotine
- Quinine
Correct Answer: Scopolamine (hyoscine)
Q18. How does atropine produce mydriasis when used as an ophthalmic agent?
- Stimulates alpha-adrenergic receptors of the iris dilator muscle
- Blocks M3 muscarinic receptors of the iris sphincter causing relaxation
- Inhibits pupillary light reflex at the optic nerve
- Chelates calcium in the ciliary body causing contraction
Correct Answer: Blocks M3 muscarinic receptors of the iris sphincter causing relaxation
Q19. Which analytical impurity limit test is important for atropine sulfate powder to ensure patient safety?
- Residual solvent analysis only
- Heavy metals limit test and microbial limit test
- Only pH measurement
- Color matching against a reference chart only
Correct Answer: Heavy metals limit test and microbial limit test
Q20. Why is racemization relevant in the industrial context of atropine production?
- Racemization converts an inactive isomer to an inactive impurity
- Racemization of hyoscyamine produces atropine, affecting potency and activity profile
- Racemization removes tropane skeleton making purification easier
- Racemization prevents formation of sulfur salts
Correct Answer: Racemization of hyoscyamine produces atropine, affecting potency and activity profile
Q21. Which solvent system is typically preferred for extracting the free base of atropine from basified aqueous solution?
- Water alone
- Nonpolar organic solvents such as chloroform or dichloromethane
- Pure methanol only
- Supercritical water at high temperature
Correct Answer: Nonpolar organic solvents such as chloroform or dichloromethane
Q22. In the industrial esterification step to make atropine, what functional group from tropic acid reacts with the tropane alcohol/amine?
- Carboxylic acid group forming an ester linkage
- Amide group forming a peptide bond
- Aldehyde group forming an acetal
- Nitro group forming a nitroso linkage
Correct Answer: Carboxylic acid group forming an ester linkage
Q23. Which safety consideration is critical when handling concentrated plant extracts rich in atropine at the manufacturing scale?
- They are non-toxic and require no special PPE
- Use of respirators and full protective equipment because alkaloid exposure can cause systemic anticholinergic effects
- Only gloves are necessary since skin contact is harmless
- They are explosive and require inert atmosphere handling
Correct Answer: Use of respirators and full protective equipment because alkaloid exposure can cause systemic anticholinergic effects
Q24. For organophosphate poisoning, how is atropine used in emergency treatment?
- Single low dose given once, no monitoring required
- Repeated large doses titrated to clearance of bronchorrhea and bronchospasm, often combined with oxime therapy
- As the only antidote required, no other therapy necessary
- Topical ocular drops are sufficient for systemic poisoning
Correct Answer: Repeated large doses titrated to clearance of bronchorrhea and bronchospasm, often combined with oxime therapy
Q25. Which property of atropine influences its ability to cross the blood–brain barrier and cause central effects?
- High polarity and permanent charge
- Low molecular weight and moderate lipophilicity in the free base form
- Inability to form salts
- Extremely large molecular size preventing penetration
Correct Answer: Low molecular weight and moderate lipophilicity in the free base form
Q26. Which in-process control parameter most directly affects alkaloid yield during plant extraction?
- Extraction pH, solvent choice, and contact time
- Color of the plant material only
- Ambient noise in the production area
- Phase of the moon during harvest
Correct Answer: Extraction pH, solvent choice, and contact time
Q27. In HPLC assay of atropine, which detector characteristic is typically exploited for sensitive quantitation?
- Flame ionization detection of nitrogen
- UV absorbance due to aromatic tropic ester chromophore
- Refractive index detection only
- Conductivity detection at high salt
Correct Answer: UV absorbance due to aromatic tropic ester chromophore
Q28. Which contraindication is most important to consider when prescribing atropine for ophthalmic use?
- Open-angle glaucoma
- History of seasonal allergic conjunctivitis
- Hypothyroidism
- Corrected myopia
Correct Answer: Open-angle glaucoma
Q29. What is a typical manufacturing control to minimize unwanted formation of related alkaloid impurities like scopolamine during processing?
- Avoiding acidification steps entirely
- Controlling extraction temperature, pH, and oxidation conditions
- Using strong oxidizers to degrade impurities
- Exposing extracts to sunlight to photodegrade impurities
Correct Answer: Controlling extraction temperature, pH, and oxidation conditions
Q30. Which statement best describes the role of pharmacopeial monographs (e.g., USP, BP) for atropine products?
- They only provide historical context and are optional
- They define identity tests, assay methods, purity limits, and storage conditions required for quality and regulatory compliance
- They mandate specific manufacturing sites for atropine production
- They are confidential documents available only to manufacturers
Correct Answer: They define identity tests, assay methods, purity limits, and storage conditions required for quality and regulatory compliance
I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
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