Materials.
Goatskin as a source of gelatin purchased at Ciputat Slaughterhouse, distilled water, sodium sulfide (VWR Chemicals, Belgium), calcium hydroxide (Merck, Germany) and Hydrochloride acid (Merck, Germany). The paracetamol tablets were formulated using the following materials: paracetamol (Anqiu Lu’an Pharmaceutical, China), amylum (PIM Pharmaceuticals, Indonesia), lactose monohydrate (DFE Pharma, Germany), goatskin gelatin or bovine gelatin (Rousselot, USA), sodium starch glycolate (Yung Zip Chemical, Taiwan), magnesium stearate (FACI Asia Pacific, Singapore)) and colloidal silicon dioxide (Cabot Blue Star Chemical, China).
Preparing Goatskin Gelatin.
The preparation to extract gelatin form goatskin referred to the method applied by Zilhadia et al. (2018)5. The hair from the goatskin was removed using a solution of calcium hydroxide and sodium sulfide. The goatskin was then washed up until its pH becomes neutral (6–7). The skin was cut into pieces and hydrolyzed with 4% hydrochloric acid solution at 5° C for 48 hours. After the acid hydrolysis process, the skin was washed again and neutralized with distilled water. The gelatin was extracted from the goatskin using distilled water at 60–70°C for 9 hours. The extract generated from the skin was filtered with vacuum filtration. The filtrate was, in turn, concentrated in the oven at 70° C for 2 hours, and was then cooled down in a refrigerator at 5° C until it formed a gel. Further, the gel was stored in a container to be dried in an oven at 60° C until dried and transparent gelatin sheets were formed. The gelatin sheets were pulverized and weighed as dry weight. At last, their contents including moisture, ash, fat, protein content and pH were evaluated.
The moisture, ash, fat and crude protein contents of gelatin extracted were determined according to Association of Official Analytical Chemists (2000) methods number 927.05, 942.05, 920.39 B and 984.13, respectively6. The pH values of gelatin solutions were measured using the British Standard Institution method (1975)7. All measurements were performed in triplicate.
Composition of Tablets.
Paracetamol tablets were formulated with 6 formulas consisting of 3 comparison formulas (CF) and 3 test formulas (TF). The formulas to make paracetamol tablets with 650 mg each was presented in Table 1. Each formula was made into 500 tablets.
Table 1
Formulation of paracetamol tablets using goatskin gelatine (test formula) or bovine gelatine (comparison formula) as a binder
Ingredient
(mg)
|
Comparison Formula
|
Test Formula
|
2%
|
3%
|
4%
|
2%
|
3%
|
4%
|
Paracetamol
|
500
|
500
|
500
|
500
|
500
|
500
|
Amylum
|
65
|
65
|
65
|
65
|
65
|
65
|
Lactose Monohydrate
|
35.75
|
29.25
|
22.75
|
35.75
|
29.25
|
22.75
|
Bovine Gelatin
|
13
|
19.5
|
26
|
-
|
-
|
-
|
Goat Gelatin
|
-
|
-
|
-
|
13
|
19.5
|
26
|
Sodium Starch Glycolate
|
26
|
26
|
26
|
26
|
26
|
26
|
Magnesium Stearate
|
6.5
|
6.5
|
6.5
|
6.5
|
6.5
|
6.5
|
Colloidal Silicon Dioxide
|
3.5
|
3.5
|
3.5
|
3.5
|
3.5
|
3.5
|
Preparation of Tablets.
Paracetamol tablets were manufactured using conventional wet granulation process with slight modification8,9. Paracetamol was mixed with amylum and lactose monohydrate in a mortar until the powder was homogenous, then granulated with gelatin solution in hot water. The generated granules were dried at 60oC until they produced moisture at 2.5%. The dried granules were sifted with number 20 sieve (Quadrocomill U5, USA). Some evaluation was made to the granules including their flow rate, angle of repose test, compressibility, moisture and particle size distribution10. Sodium starch glycolate, magnesium stearate and colloidal silicon dioxide were added to the granules and mixed until they were homogenous. The tablets were at last compressed in single punch tablet press (Manesty F3, United Kingdom).
Evaluation of Tablets.
Paracetamol tablets were evaluated with a suitable method. Weight variation and thickness uniformity were measured with electronic weighing balance (Mettler Toledo, Japan) and callipers (Mitotuyo, Japan), respectively. The hardness tablet testing was measured with hardness tester (Erweka, Germany). Friability testing was conducted using friabilator tester (Erweka, Germany) at the speed of 25 rpm and the percentage of weight loss was then calculated. Disintegration testing was applied with disintegration test machine (Erweka, Germany).
In vitro drug release study.
Dissolution testing was performed using method described in Indonesian Pharmacopoeia (2014)11. 900 ml phosphate buffer with a pH of 5.8 was placed into the dissolution flask, and the paddle stirrer was set at 50 rpm speed. Tablets were put into six dissolution flasks each and the temperature was maintained at 37oC ± 0.5oC. After 30 minutes, 5 ml sample was taken out and the absorption of paracetamol released was measured with UV-VIS Spectrophotometer (Agilent, USA) at the maximum wavelength (243 nm).