Development and characterization of surface engineered PPI dendrimers for targeted drug delivery

Figures & data

Table 1. Optimization parameters for 5.0G dendrimers.

Formulation code	5.0G PPI dendrimers: MTX (weight ratio)	Average particle size (nm)	Polydispersity index (PDI)	% loading efficiency
FM1	1:2	24.73 ± 0.20	0.17 ± 0.04	98.93 ± 0.02
FM2	1:4	25.56 ± 0.15	0.24 ± 0.04	99.48 ± 0.11
FM3	1:10	22.56 ± 0.20	0.17 ± 0.02	± 0.01

Table 2. Experimental layout for pharmacokinetic and organ distribution studies.

Study	Name of animal	Groups			R.O.A	Total animals
		G-1	G-2	G-3
		Free MTX	MTX–PPI conjugate	MTX– FA–PPI conjugate
Pharmacokinetic study	Wistar rats	1X6	1X6	1X6	i.v.	18
Tissue/Organ biodistribution study

Figure 1. IR spectrum of 5.0G PPI dendrimers.

Figure 2. IR spectrum of MTX–PPI conjugate.

Figure 3. IR spectrum of FA–PPI conjugate.

Figure 4. ¹H NMR spectrum of FA–PPI conjugate.

Figure 5. SEM image of MTX–FA–PPI conjugate.

Figure 6. Size, polydispersity index of MTX-FA-PPI conjugate.

Figure 7. IR spectrum of MTX–FA–PPI conjugate.

Table 3. Reported and observed peaks of MTX–FA–PPI conjugate.

Groups	Standard peak (cm^−1)	Observed peak (cm^−1)
CO–NH (amide)	1680–1630	1659.46
C–H bend (alkane)	1450–1375	1439.72
C–N (amines)	1350–1000	1109.71
C–O (alcohols, esters)	1300–1000	1253.92
C–H out-of-plane bend (alkene)	1000–650	665.87
C–N (amines)	1350–1000	1060.50

Figure 8. DSC of MTX-FA-PPI conjugate.

Figure 9. In vitro drug release profile of MTX–PPI and MTX–FA–PPI conjugate in PBS pH 7.4 and acetate buffer pH 5.0.

Figure 10. Percent cell viability of MCF-7 cells treated with various formulations after 24 h.

Figure 11. (A) Qualitative uptake of (a) MTX, (b) MTX-PPI, and (c) MTX-FA-PPI conjugates and (B) quantitative uptake in MCF-7 cells; (FA) representing pre-incubation with folic acid.

Figure 12. Plasma concentration versus time curve for various formulations.

Table 4. Plasma pharmacokinetic parameters of different formulations.

Parameters	MTX–FA–PPI conjugate	MTX–PPI conjugate	Plain drug
Cmax (μg/mL)	4.53	3.06	2.54
Tmax (h)	1.00	1.00	1.00
T1/2 (h)	9.97	7.99	5.66
AUCtotal (μg/μL/h)	52.70	29.33	19.24
MRT	15.16	11.74	7.56

AUC: Area under curve; C_max: Maximum concentration of drug; T_max: Peak time when drug achieves C_max; MRT: Mean residence time.

Figure 13. Percent drug in amount with respect to time in different organs.