What is a ternary solid dispersion in pharmaceutical formulation?

A ternary solid dispersion is a formulation where a poorly soluble drug is molecularly dispersed within a matrix made of two different carrier polymers. In the case of meloxicam, the drug was combined with moringa coagulant (a natural protein extracted from moringa seeds) and polyvinylpyrrolidone (PVP K30, a synthetic polymer). The two polymers work together to force the drug into an amorphous, high-energy state that dissolves much more readily than its crystalline form, while also preventing it from recrystallizing during storage.

How does ball milling improve meloxicam dissolution compared to physical kneading?

Ball milling supplies significantly more mechanical energy than manual physical kneading, which leads to better molecular-level mixing between the drug and the polymers. In the study, the ball-milled ternary formulation at a 1:3:1 ratio of meloxicam to moringa coagulant to PVP K30 achieved 85.18% dissolution after 6 hours. The same ratio prepared by physical kneading reached only 61.39%. The added energy from ball milling promotes more complete amorphization of the drug and stronger intermolecular interactions with the carriers.

Why is meloxicam considered a poorly water-soluble drug?

Meloxicam is a non-steroidal anti-inflammatory drug (NSAID) that dissolves very slowly in water. In dissolution testing, pure crystalline meloxicam achieved only about 13.34% dissolution after 6 hours in phosphate buffer at pH 7.4. This poor solubility limits its oral absorption and bioavailability, meaning patients may not get the full therapeutic benefit of the dose they take. Improving meloxicam's dissolution rate is a key goal in formulation science.

What is moringa coagulant and how is it extracted?

Moringa coagulant (MC) is a cationic protein biopolymer extracted from moringa tree seeds, with a molecular weight between 6 and 12 kDa. The extraction process involves delipidating the seeds, then stirring them in a 3% sodium chloride solution for about 6 hours to leach out the proteins. The extract is filtered, heated until a white precipitate forms, and then dialyzed in cold water for 8 hours to remove residual salt. A final homogenization with cold acetone strips away any remaining lipids. The yield is typically around 15% by salt extraction, which is significantly higher than plain water extraction.

How much does a ternary solid dispersion improve meloxicam dissolution?

The best-performing ternary solid dispersion, using a meloxicam-to-moringa coagulant-to-PVP K30 ratio of 1:3:1 prepared by ball milling, achieved approximately 85% dissolution after 6 hours. This is about a sixfold improvement over pure meloxicam, which dissolved only 13.34% under the same conditions. In comparison, binary dispersions with moringa coagulant alone (1:3 ratio) reached about 42% dissolution (threefold improvement), and those with PVP K30 alone (1:4 ratio) reached about 35% (2.5-fold improvement). The ternary system outperformed what either binary system achieved on its own.

What role does the synergistic effect play in ternary solid dispersions?

The synergistic effect means that the dissolution enhancement from combining moringa coagulant and PVP K30 is greater than the sum of what each polymer achieves individually. If moringa coagulant alone gives a threefold improvement and PVP K30 alone gives a 2.5-fold improvement, simply adding them would predict a 5.5-fold boost. The ternary system actually delivered a sixfold improvement. This extra gain comes from two mechanisms working together: PVP K30 improves wettability and dispersibility through its hydrophilic nature, while moringa coagulant provides abundant hydrogen-bonding sites that lock the drug in its amorphous state. The synergy is not simply a pH effect from the basic amino acids in moringa coagulant; solubility tests in unbuffered distilled water confirmed the same pattern.

How stable are meloxicam ternary solid dispersions during storage?

Under ICH-accelerated stability conditions for Zone IV (40 degrees Celsius at 75% relative humidity), the optimized ternary solid dispersion showed good stability over three months. The 6-hour dissolution rate dropped only slightly from 85.18% initially to 81.91% at 90 days. Crystallinity, tracked by differential scanning calorimetry (DSC), increased from near zero to about 24.29% over the same period, and powder X-ray diffraction patterns showed only minor new peaks. For comparison, pure ball-milled meloxicam without any stabilizers reverted to a highly crystalline state within a single month, demonstrating that the polymer combination is essential for maintaining the amorphous form.

Can moringa coagulant ternary solid dispersions be compressed into tablets?

Yes. The optimized ternary solid dispersion showed good properties for tablet formulation. Micromeritic testing produced an angle of repose of 26.77 degrees, a Carr compressibility index of 14.62, and a Hausner ratio of 1.17, all indicating good powder flow characteristics. Kawakita analysis, Heckel plots, and Leuenberger equation testing further confirmed adequate compressibility and tabletability with minimal excipient use. The formulation can be successfully compressed into tablets, which is critical for practical pharmaceutical manufacturing.

Meloxicam Ternary Solid Dispersions: How Moringa Coagulant and PVP Boost Dissolution 6-Fold

Somewhere between 40% and 70% of new drug candidates coming out of discovery labs are practically insoluble in water. That number sounds abstract until you realize what it means: nearly half of promising molecules, give or take, cannot dissolve well enough to be absorbed. Meloxicam, a widely prescribed NSAID for arthritis and inflammation, is one of those drugs. It works fine once it gets into the bloodstream. Getting it there is the problem.

A team of researchers decided to try something unconventional: pairing meloxicam with both a protein extracted from moringa tree seeds and polyvinylpyrrolidone (PVP K30), a synthetic polymer that has been used in drug delivery for decades. The combination outperformed what either ingredient could do alone, and by a margin that is worth a closer look.

Why poor solubility matters, in plain terms

When a drug is poorly soluble, your body cannot absorb it efficiently. You might take the right dose, but only a fraction of it reaches where it is needed. The rest passes through, a waste of both the active ingredient and the therapeutic window it was designed for.

Pharmaceutical scientists have a whole toolkit for dealing with this: micronization, salt formation, surfactants, cyclodextrin complexes, and, increasingly, solid dispersions. The idea behind solid dispersions is straightforward. You take a crystalline drug that stubbornly refuses to dissolve and you disperse it, at the molecular level, inside a carrier that alters its physical state. The goal is to force the drug into an amorphous form, which has higher internal energy than its crystalline counterpart and therefore dissolves more readily.

The catch is that amorphous forms are thermodynamically unstable. Left on their own, drug molecules in a high-energy state will find their way back to a low-energy crystalline lattice over time, especially if moisture or heat nudges them along. That is why you need a stabilizer: a polymer that locks the drug molecules in place and stops them from recrystallizing.

Moringa coagulant: not your typical pharmaceutical polymer

Moringa seeds are mostly known in the developing world as a cheap, effective way to purify drinking water. Crushed moringa seeds, when stirred into turbid water, cause suspended particles to clump together and settle out. The active ingredient responsible for this is a heterogeneous, cationic protein with a molecular weight in the 6 to 12 kDa range and an isoelectric point between 10 and 11.

Extracting it is not complicated. The seeds are delipidated, then stirred in a 3% sodium chloride solution for several hours. The salt helps leach the proteins out, a salting-out effect in reverse. After filtration, the extract is heated until a white precipitate forms, then the precipitate is dialyzed in cold water to remove any remaining salt. A final homogenization with cold acetone strips away residual lipids. What you end up with is moringa coagulant, or MC: a biopolymer rich in amino acids like tyrosine, phenylalanine, tryptophan, arginine, and cystine.

A previous study had already shown that MC can stabilize amorphous meloxicam. But the question was whether adding a second polymer to the mix could push dissolution enhancement even further.

Building the ternary system

The researchers prepared two types of mixtures: binary solid dispersions (meloxicam plus either MC or PVP K30 alone) and ternary solid dispersions (meloxicam plus both MC and PVP K30 together). They tested a range of drug-to-polymer ratios for the binary systems, from 1:0.5 all the way to 1:6, and five different ternary ratios.

Two preparation methods were used. The first, physical kneading, is exactly what it sounds like: triturating the drug and polymers together in a mortar with distilled water for 25 minutes using uniform speed and force. The second, ball milling, involved grinding the mixtures in stainless steel jars with stainless steel balls for optimized times (8 hours for MC-rich formulations, 12 hours for PVP-rich ones) at 100 rpm.

After drying in a hot air oven at no more than 40 degrees Celsius for 12 hours, the resulting powders were ready for testing.

What the characterization data actually says

Three solid-state techniques were used to figure out what was going on at the molecular level: Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). Each one told a slightly different part of the same story.

FTIR told the interaction story

The infrared spectrum of the ternary solid dispersion showed clear signs that the three components were not just sitting next to each other. Peaks shifted and broadened across the board. The O-H and N-H stretching bands of MC and meloxicam overlapped in a way that pointed straight at hydrogen bonding. Meanwhile, the S=O and C=N peaks of meloxicam dropped in intensity. Low-frequency region peaks of PVP K30 and meloxicam between 400 and 1000 cm⁻¹ shifted only slightly, which meant the overall molecular symmetry of meloxicam was being preserved even as it was hydrogen-bonded to MC.

The takeaway: the drug was interacting strongly with both polymers, and the peak broadening pointed toward full amorphization.

DSC confirmed the amorphization

Thermal analysis backed up the FTIR findings. Pure crystalline meloxicam showed a sharp endothermic melting peak with an onset around 257.6 degrees Celsius. In the ternary dispersion, that peak was dramatically broadened and reduced in intensity. It had shifted down to about 250.2 degrees Celsius. This is classic amorphous behavior. No thermal events corresponding to free, crystalline meloxicam were detected at all.

MC showed its own characteristic endothermic peaks at 80 degrees Celsius (transition point) and 239.4 degrees Celsius (melting point), while PVP K30 had endothermic peaks at 102 and 138.2 degrees Celsius. The broad endotherm between 60 and 100 degrees Celsius in the ternary system was chalked up to water loss from MC, not drug crystallinity.

PXRD confirmed the structural transformation

X-ray diffraction of pure meloxicam was textbook crystalline: sharp, intense peaks everywhere. MC was mostly amorphous to begin with, while PVP K30 showed some crystalline character. The ternary dispersion spectrum was different from all of them. The peaks were fewer and far less intense. What you saw was essentially a weighted superposition of the three component spectra, but with dramatically reduced crystallinity across the board.

All three techniques converged on the same conclusion: the ball-milled ternary solid dispersion achieved near-complete amorphization of meloxicam, and the drug was molecularly dispersed and hydrogen-bonded within the MC-PVP K30 matrix.

The dissolution numbers that actually matter

This is where the ternary system really pulled ahead. Pure meloxicam managed a dissolution of about 13.34% after 6 hours. That is the benchmark, and it is not great.

The binary combinations made real progress. Meloxicam-MC at a 1:3 ratio, prepared by ball milling, reached 42.10% dissolution at 6 hours, roughly a threefold improvement. Meloxicam-PVP K30 at 1:4, also ball-milled, hit 35.43%, about a 2.5-fold improvement. Physical kneading versions of the same binary formulations performed worse across the board, which makes sense: mechanical milling supplies more energy and creates better molecular-level mixing.

But the ternary formulation at a meloxicam-MC-PVP K30 ratio of 1:3:1, prepared by ball milling, is where the numbers really jump out. It reached 85.18% dissolution at the 6-hour mark. That is roughly a sixfold increase over pure meloxicam. The same ternary ratio prepared by physical kneading achieved 61.39%, which is respectable, but still well short of the ball-milled version.

There also seemed to be an upper limit to how much polymer you could add before dissolution performance stopped improving, and even started to drop slightly. For MC alone, the sweet spot was 1:3. For PVP K30 alone, it was 1:4. Pushing past those ratios did not help and may have caused polymer entanglement effects that hindered drug release.

The synergy piece that makes the ternary system work

What stood out was that the dissolution enhancement from the ternary system was not simply additive. If MC alone gave a threefold improvement and PVP K30 alone gave a 2.5-fold improvement, adding them together did not give you a 5.5-fold boost. It gave you a sixfold boost. That extra margin, that synergistic edge, is what makes ternary systems worth the extra complexity.

The researchers ruled out the possibility that the synergy was just a pH effect from the basic amino acids in MC. They ran solubility tests in unbuffered distilled water and found the same pattern: the ternary system delivered equilibrium solubility roughly twice that of the meloxicam-MC binary and about 2.5 times that of the meloxicam-PVP K30 binary.

The explanation comes down to two mechanisms. PVP K30 is hydrophilic, improving wettability and dispersibility. MC provides hydrogen-bonding sites that lock the drug in its amorphous state. When you combine them, both effects operate at the same time and reinforce each other.

Tabletability and stability: the practical considerations

A formulation that dissolves beautifully but cannot be compressed into a tablet is not much good to anyone. The researchers ran a full suite of micromeritic tests on the optimized ternary batch. The angle of repose came in at 26.77 degrees, the Carr compressibility index at 14.62, and the Hausner ratio at 1.17. All three values pointed to good flow properties, which is what you want when you are feeding powder into a tablet press.

Kawakita analysis gave constants of a = 0.5789 and b = 0.05906, indicating substantial volume reduction with tapping and good overall compressibility. The mean yield pressure from Heckel analysis was 1.806 tons, and the Leuenberger compactibility and compression susceptibility values further confirmed that the powder could be compressed into tablets with minimal excipient use.

Stability testing was done under ICH-accelerated conditions for Zone IV: 40 degrees Celsius at 75% relative humidity, with samples pulled at 1, 2, and 3 months. The dissolution performance degraded only slightly. At the end of 90 days, the 6-hour dissolution was still 81.91%, down from 85.18% initially. The percent crystallinity, tracked by DSC, increased from essentially zero to 24.29% over the same period. PXRD patterns at 1, 2, and 3 months showed only minor new peaks of low intensity.

Meanwhile, pure ball-milled meloxicam stored under the same conditions reverted to a highly crystalline state within a single month. A sharp new DSC peak appeared at 244.89 degrees Celsius, and PXRD peak intensity shot up. Without the polymers, the amorphous state collapsed almost immediately. With MC and PVP K30 together, it held up well.

What this means for drug formulation

There are two things worth paying attention to. The first is that a naturally sourced biopolymer, extracted from a tree seed that has been used for water purification for centuries, can hold its own as an amorphous-state stabilizer alongside a well-established synthetic polymer like PVP. The second is that ternary solid dispersions, where two polymers work together rather than one working alone, can deliver dissolution enhancement beyond what either polymer achieves by itself.

Ball milling was the more effective preparation method, and the ternary ratio of 1:3:1 (meloxicam to MC to PVP K30) was the best performer. The formulation showed good flow properties, good compressibility, and acceptable stability under accelerated conditions for at least three months.

Does this mean moringa-based ternary dispersions are replacing existing meloxicam formulations tomorrow? Not even close. Pharmacokinetic studies in animal models, bioavailability comparisons against commercial products, longer-term stability data, and scale-up validation all need to happen first. But as a proof of concept, the numbers are solid. A cheap, abundant natural protein combined with a commodity synthetic polymer produced a sixfold dissolution enhancement for a drug that needs it. If you work in formulation science, that is the kind of result you file away and keep thinking about.