A green TLC densitometric method for the simultaneous detection and quantification of naphazoline HCl, pheniramine maleate along with three official impurities

Table 2 Parameters required for system suitability tests of TLC densitometric method

Parameter	NPZ impurity B	NPZ	PHN	PHN impurity A	PHN impurity B
R_f	0.18	0.35	0.49	0.63	0.83
Resolution (Rs)	NA	1.50	1.58	1.40	1.64
Tailing factor (T)	1.50	0.80	1.30	1.20	1.20
Retention factor (k')^a	4.56	1.86	1.04	0.59	0.20
Selectivity factor (α)^b	NA	2.45	1.79	1.76	2.95
Column efficiency (N)^c	262.44	196.00	635.04	425.11	737.86
Height equivalent to theoretical plate (mm)	0.034	0.046	0.014	0.021	0.012

^aRetention factor (k') = (1 − R_f)/R_f
^bCalculation of α = k'2/k'1
^cColumn efficiency (N) = 16 (z/w)², where z is the migration length of the spot, w is the spot width

ISSN: 2661-801X