Solubility Improvement and Bioavailability Enhancement

Poor water solubility and low bioavailability are two of the most common challenges in drug product development today. Over half of marketed APIs suffer from solubility challenges, and as many as 90% of new drug candidates will pose the same problems for formulators.

At LLS Health, we know that formulating BCS Class II and IV compounds is not one-size-fits-all. That is why we employ a range of techniques to achieve your goals. We are a full-service partner, offering formulation, manufacturing, and analytical support services for a range of dosage forms.

Solubility-Enhancing Excipients

Apisolex™ Polymer

The Apisolex polymer is an injectable-grade poly(amino acid) based co-polymer that has been shown to increase the solubility of hydrophobic APIs by up to 50,000 times where other commonly-used excipients fail.

Robustly patented, safe, efficient, and scalable, Apisolex formulations can achieve drug loading up to 40%, dramatically increase the achievable concentration of API in water, and reconstitute in saline in less than 30 seconds.

Apinovex™ Polymer

Lubrizol’s Apinovex polymers are GMP-validated, high molecular weight polyacrylic acid excipients designed to provide both processing and formulation benefits for spray-dried amorphous solid dispersions (ASDs).

Apinovex polymers enable formulators to achieve stable, high drug loading (up to 80%) and up to 10x improvement in drug release for crystalline APIs. With Apinovex, formulators can develop efficient, IP-protected oral solid dosage forms for a range of poorly soluble APIs.

API Physical Modification Services


A process by which the particle size of an API is reduced in a liquid vehicle (typically aqueous) via grinding using polymeric or ceramic beads to increase dissolution rate. This technique is also referred to as high energy media milling.

Learn more about Nanomilling services.


Another particle size reduction technique that commonly uses pressurized air (jet milling) to achieve micron-scale particles with higher dissolution rates.


A technique where API molecules and co-crystal formers (AKA co-formers) form a single crystal lattice with higher solubility than the individual components.

Amorphous Solutions and Dispersions

A technique where API particles are dispersed in an excipient (via hot melt extrusion or spray drying) to stabilize the API in an amorphous state, leading to higher solubility.

Learn how Lubrizol’s Apinovex™ polymers enable spray-dried amorphous solid dispersions with stable, high drug loading and up to 10x improvement in drug release for crystalline APIs.

API Chemical Modification Services

pH Modification

A technique where the solubility of ionizable APIs is increased through the addition of acidic of basic excipients to a formulation.

Salt Formation

A process where the salt form of an ionizable API is formed by coupling the API with a counterion and crystallization solvents. Salt forms often exhibit higher solubility.


A technique where polyethylene glycol (PEG) is covalently or non-covalently bound to the surface of a large molecule, small molecule, or liposomal carrier, improving the solubility and half-life of an API.

Encapsulation Techniques


Structures comprised of surfactants, which are amphiphilic compounds with a hydrophobic tail and hydrophilic head. Micelles are typically spherical and consist of a hydrophobic core for solubilizing API and a hydrophilic outer surface which faces the surrounding aqueous environment.

Learn how Lubrizol’s Apisolex™ polymer micelle technology increases the solubility of hydrophobic APIs by up to 50,000 times where other commonly-used excipients fail.


Structures comprised of one or more phospholipid bi-layers. Liposomes are typically spherical and are used to encapsulate water-soluble APIs in the core, oil-soluble APIs in the bilayer membrane(s), and, if made of cationic phospholipids, trap and deliver oligonucleotides for gene therapy.

Solid-Lipid Nanoparticles

Nano-scale particles comprised of lipidic materials (usually phospholipids, triglycerides, and natural waxes) which can solubilize a wide range of small and large molecule APIs.

Learn more about Solid-Lipid Nanoparticles.

Inclusion Complexes


Torus-shaped structures with a hydrophilic outer surface and a hollow, hydrophobic core where poorly water-soluble APIs are entrapped and carried to their site of action.

Serum Albumin

A biocompatible, naturally-occurring protein which is complexed with APIs to form bioresorbable nanoparticles with improved dissolution rates.