A tissue sealant for use in surgical and medical procedures for sealing the tissues of a living mammal is provided. The tissue sealant comprises a hydrogel which is formed by gelation of a premix disposed on the tissue to be sealed. The premix comprises alkylated chitosan or a gelatin, and a polybasic carboxylic acid or an oxidized polysaccharide, in an aqueous medium. The premix can also include a dehydrating reagent, a carboxyl activating reagent, or both. A specific use of the tissue sealant is in the repair of the dura mater after brain surgery to prevent leakage of cerebrospinal fluid. The tissue sealant may include a therapeutic or protective agent such as an antibiotic or an anti-inflammatory drug.

Provided herein are in vivo gelling ophthalmic pre-formulations forming a biocompatible retinal patch comprising at least one nucleophilic compound or monomer unit, at least one electrophilic compound or monomer unit, and optionally a therapeutic agent and/or viscosity enhancer. In some embodiments, the retinal patch at least partially adheres to the site of a retinal tear. Also provided herein are methods of treating retinal detachment by delivering an in vivo gelling ophthalmic pre-formulation to the site of a retinal tear in human eye, wherein the in vivo gelling ophthalmic pre-formulation forms a retinal patch.

Pharmaceutical gels and methods for delivering a therapeutic agent to a target tissue site beneath the skin of a patient are provided, the gel being capable of adhering to the target tissue site and comprising one or more biodegradable depots containing an effective amount of the therapeutic agent. In various embodiments, the gel is sprayable and hardens after contacting the target tissue site.

Compounds comprising a tetrapyrrole macrocycle that includes a radionuclide; a hydrogelator attached to the tetrapyrrole macrocycle; a water solubilizing group attached to the hydrogelator; and a cleavage site that is between the hydrogelator and the water solubilizing group are described herein along with their methods of use. Two or more compounds of the present invention may two or more compounds may self-assemble (e.g., aggregate), optionally in vivo.

An injectable depot formulation includes a biocompatible polymer, an organic solvent combined with the biocompatible polymer to form a viscous gel, and a small molecule drug incorporated in the viscous gel such that the formulation exhibits an in vivo release profile having C.sub.max to C.sub.min ratio less than 200 and lag time less than 0.2.

Radioactive hydrogels for the delivery of localized radiotherapy, methods of making the radioactive hydrogels, and methods of using the radioactive hydrogels are disclosed. A radioisotope may be conjugated to a high molecular weight molecule, which may be encapsulated in a microparticle, where the microparticle is then dispersed within a hydrogel. The radioactive hydrogel may prevent leakage of the radioisotope to provide radiotherapy to a surgical margin while minimizing damage to surrounding normal tissue.

The present disclosure provides bioorthogonal compositions for delivering agents in a subject. The disclosure also provides methods of producing the compositions, as well as methods of using the same.

Provided herein are in vivo gelling ophthalmic pre-formulations forming a biocompatible retinal patch comprising at least one nucleophilic compound or monomer unit, at least one electrophilic compound or monomer unit, and optionally a therapeutic agent and/or viscosity enhancer. In some embodiments, the retinal patch at least partially adheres to the site of a retinal tear. Also provided herein are methods of treating retinal detachment by delivering an in vivo gelling ophthalmic pre-formulation to the site of a retinal tear in human eye, wherein the in vivo gelling ophthalmic pre-formulation forms a retinal patch.

The present invention provides a method for selective delivery of a therapeutic or diagnostic agent to a targeted organ or tissue by implanting a biocompatible solid support in the patient being linked to a first binding agent, and administering a second binding agent to the patient linked to the therapeutic or diagnostic agent, such that the therapeutic or diagnostic agent accumulates at the targeted organ or tissue.

The present invention provides a method for selective delivery of a therapeutic or diagnostic agent to a targeted organ or tissue by implanting a biocompatible solid support in the patient being linked to a first binding agent, and administering a second binding agent to the patient linked to the therapeutic or diagnostic agent, such that the therapeutic or diagnostic agent accumulates at the targeted organ or tissue.