Traditionally, oral drugs in pill or capsule form have been designed to release the dose of medicine in the upper gastrointestinal tract, where drugs are more readily dissolved and absorbed. New research has targeted the colon as an ideal environment for drug absorption to treat certain illnesses. To reach the colon, the drug must first pass through the stomach and small intestine. Table 1 details several drug-delivery systems.

The following experiments test two of the drug-delivery systems:

Experiment 1 Bacteria-dependent delivery.This experiment measured the average time it took a coated tablet to travel from the stomach (gastric emptying) through the small intestine (small intestine transit) to arrive in the colon. Twelve healthy men aged 23 to 25 years old and weighing between 55 and 70 kilograms (kg) who had fasted overnight were divided into 3 groups. They each swallowed 1 tablet, which contained a tracer (A or B) and 1 of 2 natural coatings (1 or 2). The location of the tracer was measured every half-hour for 12 hours. The average times are recorded in Table 2.

Experiment 2 Time-dependent delivery.The methods were the same as those used in Experiment 1, except that the tablets all contained the same tracer and 1 of 2 outer coatings (A or B) and one of two inner coatings (1 or 2). The average times are recorded in Table 3.

4. Which average time is standard for both experi-ments? F. Small intestine transit time. G. Colonic arrival time. H. Small intestine transit time and colonic arrival time. J. Gastric emptying time.

5.Which of the following is true about time-dependent delivery? A. Synthetic polymers may be unsafe and may disintegrate in the stomach. B. Taking food may disintegrate the capsule before it reaches the colon. C. Delivery depends on the bacteria in the colon for delivery. D. An inner barrier delays release of the medicine.

Answers

The correct answer is C. To answer this question, look at the list of drawbacks for each drug- delivery system. According to Table 1, in the Pressure drug-delivery system, ‘‘food taken with the capsule may alter the pressure enough to disintegrate the capsule in the stomach.’’

The correct answer is G. The passage states that ‘‘new research has targeted the colon as an ideal environment for drug absorption to treat certain illnesses.’’ This suggests that the intended target in these experiments is the colon. According to the results of Experiment 2 (found in Table 3) the tablet with the ‘‘A’’ outer coating and the ‘‘2’’ inner coating reached the colon in the shortest amount of time.

The correct answer is B. The results of Experiment 1 are shown in Table 2. Both Group I and Group II included tablets with Tracer A, but the tablets in each group had different coatings. Therefore, it is most likely that the coating, not the tracer would have a greater impact on either gastric emptying time or colonic arrival; eliminate answer choices A and D. Since the target is the same for all groups (the colon) the drug’s target destination will not be affected; eliminate answer choice C. You can see that with Coating 2, the colonic arrival time is faster than with Coating 1, which best supports answer choice B.

ThecorrectanswerisJ.Accordingtotheresultsof both experiments, across all groups, the time that remained standard, or constant, was the gastric emptying time, answer choice J.

The correct answer is D. Table 1 provides details about each drug-delivery system. When you locate Time-dependent delivery, you see that the mechanics of the delivery include an inner barrier that delays release, answer choice D. The other answer choices are not associated with time- dependent delivery. ​​