LOW-FRICTION COATINGS FOR SYRINGES AND RELATED METHODS
Coatings for syringe plunger tips, as well as syringes and syringe components including such coatings, are disclosed. A material of the coating may have at least one different material property than a material of the syringe component to which it is applied. The coatings may provide a reduced coefficient of friction between the coating and a surface of the syringe relative to the coefficient of friction between the uncoated component and the syringe surface. Methods for manufacturing a syringe or syringe component including such coatings, as well as methods for isolating a substance in a syringe from a syringe component, are also disclosed.
1 . A syringe comprising:
a barrel comprising an interior surface;
a plunger comprising:
an elongate handle portion defining a proximal end and a distal end; and
a plunger tip coupled to the distal end of the elongate handle portion, the plunger tip comprising a first material and including an annular wall and a top portion coupled to the annular wall; and
a coating disposed on at least a portion of an external surface of the plunger tip, the coating comprising a second material,
wherein at least one material property of the first material differs from at least one material property of the second material.
2 . The syringe of claim 1 , wherein the second material comprises polyethylene, perfluoropolyether (PFPE), or perfluoropolyalkylether (PFAE).
3 . The syringe of claim 2 , wherein the second material comprises linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), expanded polytetrafluoroethylene (ePTFE), polytetrafluoroethylene (PTFE), or composites thereof.
4 . The syringe of claim 1 , wherein a coefficient of friction between the second material and the interior surface is lower than a coefficient of friction between the first material and the interior surface.
5 . The syringe of claim 1 , wherein the coating isolates the first material from a substance loaded in the reservoir by preventing physical contact between the first material and the substance.
6 . The syringe of claim 5 , wherein the plunger tip comprises silicone and the substance comprises polyvinyl alcohol (PVA) or gelatin foam.
7 . The syringe of claim 1 , wherein the coating is absent from the external surface of a portion of the annular wall.
8 . The syringe of claim 1 , wherein the syringe is free of liquid silicone lubricants.
9 . The syringe of claim 1 , wherein the coating has a thickness from about 0.1 μm to about 50 μm.
10 . The syringe of claim 1 , wherein the coating is adhered to at least a portion of an external surface of the plunger tip.
11 . The syringe of claim 1 , wherein the coating is covalently bonded to the portion of the external surface of the plunger tip.
12 . The syringe of claim 1 , wherein the plunger tip and coating comprise a geometric coupling feature.
13 . A syringe component comprising:
a plunger tip comprising a first material, and including an annular wall and a top portion coupled to the annular wall;
a coating disposed on at least a portion of an external surface of the plunger tip, the coating comprising a second material,
wherein at least one material property of the first material differs from at least one material property of the second material.
14 . The syringe component of claim 13 , wherein a coefficient of friction between the second material and an interior surface of a syringe is lower than a coefficient of friction between the first material and the interior surface of the syringe.
15 . The syringe component of claim 13 , wherein the coating is configured to isolate the first material in the plunger tip from a substance loaded in a reservoir defined by an interior surface of a syringe by preventing physical contact between the first material and the substance.
16 . A method of manufacture of a syringe assembly, comprising applying a coating to a plunger tip,
wherein the plunger tip comprises a first material, the coating comprises a second material, and
wherein at least one material property of the first material differs from at least one material property of the second material.
17 . The method of claim 16 , wherein applying the coating to the plunger tip comprises depositing the second material onto an external surface of the plunger tip.
18 . The method of claim 17 , wherein depositing comprises dip coating, sputtering, spray coating, or spin coating the second material onto the external surface.
19 . The method of claim 16 , further comprising covalently bonding the second material to the external surface.
20 . The method of claim 16 , further comprising coupling the plunger tip to a syringe plunger.