Table 2.

Experimental and HPLC method parameters

	Atridox	Arestin	PerioChip
API	Doxycycline hyclate	Minocycline HCl	Chlorhexidine gluconate
Delivery system	Multi-dose Atrigel system	Bioresorbable microsphere	Gelatin matrix
Experimental Setting
Tested dose	Single dose: 10 mg Partial dose: 7.5 mg	Single dose: 4 mg Partial dose: 3 mg	Single dose: 7 mg Partial dose: 3.5 and 5 mg
Sampling time points	2, 4, 8, 18, 24, 48, 72, 96, 120, 144, and 168 h	0.5, 1, 2, 3, 6, 9, 18, 24, 48, 72, and 96 h	4, 8, 12, 16, 24, 48, 72, 96, 120, and 144 h
Outlet sampling compartment temperature	Below 10°C	Room temperature and below 10°C	Room temperature
Other modification and experiment	Release liner film blocking the product; 5, 10, and 15 mg doses under non-flow through condition	Filter paper at the outlet	None
HPLC Method Parameters
Mobile phase	32.2 mL 0.2 M tetrabutylammonium hydrogen sulfate in water, mixed with 32.2 mL 0.38 M EDTA in water and 15.6 mL water, adjusted to pH 7.0 with ammonia solution, then mixed with 20 mL acetonitrile to a final mixture of 80:20 water:acetonitrile	0.6% (v/v) triethylamine in water, adjusted to pH 3.0 with o-phosphoric acid, and mixed with acetonitrile to a final mixture of 85:15 water:acetonitrile	0.23 moles sodium phosphate monobasic in 1.39 L water, mixed with 10 mL 0.5% triethylamine in water, adjusted to pH 3.0 with o-phosphoric acid and mixed with 0.6 L acetonitrile to a final mixture of 70:30 water:acetonitrile
Flow rate	1.2 mL/min	1.2 mL/min	1.5 mL/min
Injection volume	30 μL	30 μL	50 μL
Wavelength for detection	280 nm	273 nm	239 nm
Approximate retention time	4.0 min	3.5 min	4.4 min
Run time	10 min	5 min	5 min
Standard concentration	16–750 μg/mL in mobile phase	1–200 μg/mL in mobile phase	0.1–200 μg/mL in water
Method reference	(Hofsass and Dressman, 2020)	(Matos et al., 2017)	(Ren et al., 2019)