The melting point of a substance is a critical property that indicates its purity and identity. In this study, the melting point of the Lansoprazol was determined using two different methods: the Capillary Fusion Method and Differential Scanning Calorimetry (DSC). The Capillary Fusion Method reported a melting point range of 178–181°C. Upon conducting the experiment, the observed melting point was found to be 179–181°C. This close agreement between the reported and observed melting points suggests that the sample is of high purity. DSC is a more advanced technique that provides precise thermal analysis, and the observed melting point range confirms the findings from the Capillary Fusion Method. The observed melting point range of 179–181°C was consistent across both methods, demonstrating the reliability of the data. The slight variation between the reported melting point (178–181°C) in the Capillary Fusion Method and the observed melting points is minimal and within an acceptable range.
Infrared (IR) spectroscopy is a powerful analytical technique used to identify functional groups and molecular interactions within a sample. In this study, the IR spectra of pure lansoprazole and a physical mixture of lansoprazole with excipients were compared to assess any potential interactions between the drug and excipients. The comparison between the IR spectra of pure lansoprazole and the physical mixture reveals that the primary functional groups of lansoprazole remain intact in the presence of excipients. The absence of significant shifts or disappearance of characteristic peaks suggests that there are no strong chemical interactions between lansoprazole and the excipients in the physical mixture. This indicates that the excipients do not affect the structural integrity of lansoprazole, which is crucial for maintaining its pharmacological activity.
The experiment aimed to evaluate the effects of varying amounts of two polymers (Factor 1: Polymer A and Factor 2: Polymer B) on three response variables: particle size (in nm), polydispersity index (PDI), and encapsulation efficiency (EE, in %). The particle size increased with the amount of Polymer A across all levels of Polymer B. For instance, at 900 g of Polymer B, increasing Polymer A from 400 g to 1000 g resulted in an increase in particle size from 329.7 nm to 779.8 nm. Similarly, at 1200 g of Polymer B, increasing Polymer A from 400 g to 1000 g led to a rise in particle size from 415.6 nm to 978.4 nm. The smallest particle sizes were observed with the lowest amount of Polymer A (400 g) regardless of the amount of Polymer B used. The trend suggests that the particle size is primarily influenced by the amount of Polymer A. Higher amounts of Polymer A likely contribute to increased viscosity and particle agglomeration, leading to larger particle sizes.
The PDI values varied but showed some trends. Lower PDI values (indicating more uniform particle size distribution) were generally observed with lower amounts of Polymer B. For instance, with 600 g of Polymer B, PDIs were 0.52, 0.61, and 0.63 for increasing amounts of Polymer A. Higher PDIs, indicating a broader particle size distribution, were often seen at higher amounts of Polymer B. For example, at 1200 g of Polymer B, the PDIs were 0.86, 0.89, and 0.88 for increasing amounts of Polymer A. The PDI results suggest that higher amounts of Polymer B lead to less uniform particle sizes, possibly due to the increased likelihood of forming aggregates or variations in the polymer matrix. Lower amounts of Polymer B seem to favor more uniform particle distribution.
The encapsulation efficiency (EE) showed a general trend of increasing with the amount of Polymer A when the amount of Polymer B was constant. For example, at 900 g of Polymer B, increasing Polymer A from 400 g to 1000 g increased EE from 64.59–72.81%. However, the highest EE observed (72.81%) was not significantly higher than the EEs observed at lower amounts of Polymer A and B. The EE varied with Polymer B but did not show as clear a trend as with Polymer A. For example, at 400 g of Polymer A, varying Polymer B from 600 g to 1200 g decreased EE from 62–53.79%. The encapsulation efficiency appears to be more sensitive to the amount of Polymer A. Higher amounts of Polymer A might provide better encapsulation due to increased available surface area and interaction sites for encapsulation. However, there is a point where increasing Polymer A does not significantly improve EE, indicating a possible saturation point. The data indicates that the amount of Polymer A has a significant impact on particle size, PDI, and EE. Increasing Polymer A generally leads to larger particle sizes and improved encapsulation efficiency but can also result in less uniform particle size distributions when combined with higher amounts of Polymer B. The amount of Polymer B influences PDI more strongly, with higher amounts leading to broader particle size distributions.
The table presents statistical metrics for different regression models (Linear, Two-Factor Interaction (2FI), Quadratic, and Cubic) used to fit the experimental data. The Linear model demonstrates a good fit with an R² value of 0.9474, indicating that approximately 94.74% of the variance in the data is explained by the model. The adjusted R² (0.9299) is slightly lower, which is expected as it adjusts for the number of predictors in the model. The predicted R² (0.8597) is also reasonably high, suggesting that the model has good predictive power. The relatively low PRESS value supports the model's adequacy. These metrics collectively suggest that the Linear model provides a good balance between fit and simplicity, making it a suggested model for the data. Among the models evaluated, the Linear model appears to be the most appropriate choice based on the balance of fit and predictive power. It has a high R² and adjusted R², and a reasonably high predicted R² with the lowest PRESS value, indicating good generalizability to new data. The 2FI, Quadratic, and Cubic models, despite showing higher R² values, suffer from overfitting as evidenced by their lower predicted R² values and higher PRESS values. Therefore, the Linear model is suggested for use in this analysis.
The ANOVA results indicate that both factors, the amount of Polymer A (CMC) and the amount of Polymer B (PVA), significantly influence the response variable. Factor A has a stronger effect compared to Factor B, as evidenced by its higher sum of squares and F-value. The overall model is highly significant, demonstrating that the selected factors are appropriate for explaining the variability in the response. These findings suggest that optimizing the amounts of these polymers can effectively control the response variable in the formulation process.
(PDI) The model summary statistics indicate that the model provides a strong and reliable fit to the data. The high R² and adjusted R² values demonstrate that the model explains a significant portion of the variance in the response variable. The predicted R² indicates good predictive ability, while the low standard deviation and coefficient of variation suggest precise predictions. The high adequate precision value confirms that the model has a strong signal relative to noise. Overall, these metrics collectively suggest that the model is robust, reliable, and well-suited for predicting the response variable based on the factors studied.
The ANOVA results indicate that the interaction between Polymer A and Polymer B (AB) and the quadratic term for Polymer B (B²) are statistically significant. The interaction term (AB) has a significant effect on the response variable, suggesting that the combination of these polymers plays an important role in influencing the outcome. The quadratic effect of Polymer B is also significant, indicating a strong curvature effect. In contrast, the quadratic effect of Polymer A is not significant, suggesting that the response variable does not exhibit a significant curvature effect with respect to Polymer A within the studied range.
These findings highlight the importance of considering both the interaction and quadratic effects of the polymers when optimizing the formulation to achieve the desired response. The model fits the data well, as indicated by the low residual sum of squares and the overall statistical significance of the relevant terms.
The DLS results indicate that the sample has an average particle size (Z-average diameter) of 332.4 d.nm with a moderate polydispersity index (PdI) of 0.52. The intercept value of 0.669 suggests good data quality. The size distribution by intensity shows a single peak at 290.9 d.nm with 100% intensity, indicating that the majority of particles are around this size, but there is some variability as shown by the standard deviation of 166.8 d.nm. Overall, the sample is characterized by moderately uniform particles with good quality measurements.
The zeta potential analysis results indicate that the sample has a moderate negative zeta potential of -15.3 mV, suggesting incipient instability with some potential for particle aggregation over time. The zeta deviation of 6.96 mV indicates moderate variability in particle surface charge, which can impact stability. The conductivity is low at 0.0560 mS/cm, supporting the observed zeta potential by minimizing counterion effects. The single peak in the zeta potential distribution confirms the uniformity of the surface charge across the sample.
Overall, while the sample shows reasonable stability, the moderate zeta potential indicates that it may require additional stabilization measures for long-term stability. The good quality rating of the results ensures that these findings are reliable and can be used to inform further formulation or stability enhancement efforts.
The SEM analysis of formulation F4 revealed the presence of porous, spherical, and nanoscale particles. The figure provides a clear representation of the porous and spongy nature of the nanosponges.
The Fourier-transform infrared (FTIR) spectrum of formulation batch F4 indicates the absence of significant functional peak displacement. Furthermore, the sharp peaks of the drug exhibit a decrease in intensity, suggesting that the drug has been entrapped.
The DSC thermogram of pure LPZ is shown in comparison to the optimized nanosponge formulation in the Fig. 24. The purity of LPZ was demonstrated by a endothermic melting peak, which was compatible with data in the literature. The drug melting peak was not visible on the DSC thermogram of the optimized Nanosuspension formulation (Fig. 24), and no other new peaks appeared, indicating that the drug had changed to an amorphous state. Loss of drug crystallinity also indicated uniformity of drug distribution within the matrix, which could be attributed to the presence of surfactant, which inhibits drug crystallization.
Dichloromethane was used as an organic solvent to dissolve the drug. It belongs to class two solvent and can be used in the pharmaceutical formulation with a limit of 600 ppm. The sample was analysed with respect to the dichloromethane used in the preparation and the amount of dichloromethane was found to be 453.68 ppm which is considered to be safe and within the range.
During the initial 3 hours, the %CDR increases gradually from 10.584–25.985%. This phase likely represents the initial burst release, where the drug on or near the surface of the delivery system is quickly released into the surrounding medium. Between 3 to 5 hours, there is a marked increase in %CDR, reaching up to 60.214%. This accelerated release phase indicates that the drug is being released at a higher rate, potentially due to the dissolution or diffusion mechanisms of the delivery system. From 5 to 9 hours, the %CDR continues to increase but at a slightly reduced rate, reaching 90.548%. This phase suggests a more controlled and sustained release, which is often desired in drug delivery systems to maintain therapeutic levels of the drug over an extended period. In the final phase from 9 to 11 hours, the %CDR reaches near completion, with 99.452% released by 11 hours. This indicates that most of the drug has been released, and the system has effectively delivered the drug over the specified period.
The cumulative drug release data indicates a well-defined release profile with distinct phases: an initial burst release, an accelerated release, a sustained release, and a final release phase. The drug delivery system appears to be effective in releasing the drug gradually over an 11 hour period, achieving almost complete release by the end of the study. The low standard deviations suggest that the release data is reliable and reproducible.
The in vitro drug release profile from the buccal patch demonstrates a well-defined release pattern characterized by an initial burst release, followed by an accelerated release phase, and then a sustained release phase, culminating in near-total drug release by the 8th hour. The consistency in the data, as indicated by the small standard deviations, supports the reliability of the measurements.
This release profile is advantageous for therapeutic applications requiring both an initial rapid onset of action and sustained drug delivery to maintain therapeutic levels. The effective delivery of nearly 100% of the drug within 8 hours suggests that the buccal patch formulation is efficient and suitable for potential clinical use.
Table 1
Determination of melting point
Method | Reported Melting Point | Observed Melting Point |
Capillary Fusion Method | 178–181°C | 179–181°C |
Differential Scanning Calorimetry | 179–181°C |
Table 2
Results of experimental batches
Run | Factor 1 | Factor 2 | Response 1 | Response 2 | Response 3 |
A: amount of polymer a (gm) | B: amount of polymer b (gm) | Particle size Nm | PDI | EE % |
1 | 400 | 900 | 329.7 ± 23.58 | 0.73 ± 0.21 | 64.59 ± 5.23 |
2 | 700 | 900 | 572.6 ± 32.14 | 0.75 ± 0.11 | 70.28 ± 4.28 |
3 | 1000 | 900 | 779.8 ± 12.35 | 0.69 ± 0.32 | 72.81 ± 9.54 |
4 | 400 | 600 | 332.4 ± 32.86 | 0.52 ± 0.14 | 62 ± 5.21 |
5 | 400 | 1200 | 415.6 ± 12.42 | 0.86 ± 0.18 | 53.79 ± 3.52 |
6 | 700 | 1200 | 698.2 ± 15.74 | 0.89 ± 0.20 | 60.23 ± 4.98 |
7 | 1000 | 1200 | 978.4 ± 10.68 | 0.88 ± 0.10 | 68.76 ± 5.33 |
8 | 700 | 600 | 396.8 ± 36.54 | 0.61 ± 0.31 | 65 ± 6.42 |
9 | 1000 | 600 | 752.4 ± 26.87 | 0.63 ± 0.23 | 67 ± 5.26 |
Table 3
Results of the different models for particle size
Source | Std. Dev. | R² | Adjusted r² | Predicted r² | Press | |
Linear | 61.17 | 0.9474 | 0.9299 | 0.8597 | 59872.38 | Suggested |
2fi | 58.92 | 0.9593 | 0.9349 | 0.7639 | 1.008e + 05 | |
Quadratic | 61.53 | 0.9734 | 0.9290 | 0.7157 | 1.213e + 05 | |
Cubic | 60.03 | 0.9916 | 0.9324 | -0.5390 | 6.568e + 05 | Aliased |
Table 4
ANOVA data for particle size
Source | Sum of squares | Df | Mean square | F-value | P-value | |
Model | 4.043e + 05 | 2 | 2.022e + 05 | 54.02 | 0.0001 | Significant |
A-cmc | 3.422e + 05 | 1 | 3.422e + 05 | 91.44 | < 0.0001 | |
B-pva | 62138.73 | 1 | 62138.73 | 16.60 | 0.0065 | |
Residual | 22453.48 | 6 | 3742.25 | | | |
Cor total | 4.268e + 05 | 8 | | | | |
Table 5
Results of the different models for PDI
Source | Std. Dev. | R² | Adjusted r² | Predicted r² | Press | |
Linear | 0.0365 | 0.9410 | 0.9214 | 0.8555 | 0.0196 | Suggested |
2fi | 0.0345 | 0.9560 | 0.9296 | 0.8260 | 0.0236 | |
Quadratic | 0.0357 | 0.9718 | 0.9248 | 0.6588 | 0.0462 | |
Cubic | 0.0083 | 0.9995 | 0.9959 | 0.9066 | 0.0127 | Aliased |
Table 7
Different models suggested by the software for Entrapment Efficiency
Source | Std. Dev. | R² | Adjusted r² | Predicted r² | Press | |
Linear | 4.30 | 0.5799 | 0.4399 | 0.0533 | 250.46 | |
2fi | 4.15 | 0.6739 | 0.4782 | -0.1355 | 300.40 | |
Quadratic | 1.06 | 0.9873 | 0.9661 | 0.8726 | 33.71 | Suggested |
Cubic | 1.23 | 0.9942 | 0.9539 | -0.0507 | 277.97 | Aliased |
Table 9
Drug release of optimized batch
Time | %CDR |
1 | 10.584 ± 0.52 |
2 | 15.754 ± 0.42 |
3 | 25.985 ± 0.52 |
4 | 45.245 ± 0.54 |
5 | 60.214 ± 0.65 |
6 | 74.743 ± 0.47 |
7 | 80.541 ± 0.32 |
8 | 85.245 ± 0.84 |
9 | 90.548 ± 0.21 |
10 | 95.426 ± 0.63 |
11 | 99.452 ± 0.72 |
Table 10
Result table of Drug release of Buccal film
Time | %CDR |
1 | 15.985 ± 0.42 |
2 | 31.928 ± 0.11 |
3 | 45.925 ± 0.31 |
4 | 59.142 ± 0.59 |
5 | 60.487 ± 0.38 |
6 | 75.847 ± 0.55 |
7 | 89.657 ± 0.41 |
8 | 98.542 ± 0.65 |